Merge pull request 'Site: published by CI after a push to main and after a release (#79)' (#80) from site-publish into main

Reviewed-on: #80

.gitea/workflows/ci.yml

@@ -0,0 +1,167 @@
+# CI and releases (docs/milestones/R1.md).
+#   A push to main:    the host tests, with their coverage of lib/, and the README's badges
+#                      published to the branch `badges`.
+#   A pull request:    the same tests and coverage, then the firmware (from the build cache).
+#                      A branch's pushes run nothing by themselves: its pull request runs, once.
+#   A tag v*:          the tests, then the firmware built once, clean, signed and published as a
+#                      Gitea release. The site is then rebuilt: its home page and Downloads name
+#                      the latest release when they are built (issue #79).
+#   Run by hand:       the release of a tag that exists already (the ones from before CI).
+#
+# The job runs in a plain Python image, as scripts/ci.sh does on a developer's machine, with the
+# toolchains in a Docker volume the runner allows (container.valid_volumes: roro9stack-pio): that
+# volume is the cache. No JavaScript actions, so the image needs no Node: the checkout is git.
+#
+# What the volume keeps between runs, and what makes each go stale (issue #74, R1.md):
+#   /pio/packages, /pio/platforms   toolchains and the framework: by their versions in platformio.ini
+#   .../framework-arduinoespressif32-libs/.roro-sdkconfig.defaults
+#                                   the mark that the framework is already rebuilt with our SDK settings: the
+#                                   project's sdkconfig.defaults, which isn't in git, so that every fresh
+#                                   checkout rebuilt the framework (260 s). The platform checks its hash
+#                                   against platformio.ini's settings, and rebuilds if they differ. It is kept
+#                                   inside the libraries it describes, so it goes when they are reinstalled.
+#   /pio/ci/build-cache             PlatformIO's build cache (SCons): objects by the signature of their
+#                                   sources and command line. For pull requests only: a release compiles
+#                                   its own sources from nothing.
+#   /pio/ci/ccache                  the host tests' objects (they're built for coverage, which the build
+#                                   cache can't keep: it would lose the .gcno files)
+#   /pio/ci/venv                    PlatformIO and gcovr: delete the folder to upgrade them
+# To start from nothing (a slow run, about 7 minutes): delete /pio/ci and that .roro-sdkconfig.defaults file.
+name: CI
+on:
+  push:
+    branches: [main]  # other branches are tested by their pull request: one run, not two
+    tags: ['v*']
+    # A change that touches nothing but the site and the documents it is built from runs the Site
+    # workflow only (a tag always runs this one: Gitea doesn't apply path filters to tags).
+    paths-ignore: ['site/**', 'docs/**', 'README.md', 'CONTEXT.md']
+  pull_request:
+    paths-ignore: ['site/**', 'docs/**', 'README.md', 'CONTEXT.md']
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: An existing tag to build and publish as a release
+        required: true
+
+jobs:
+  build:
+    runs-on: ubuntu
+    # A pull request from a fork would run someone else's code on our runner: not without us (Q154).
+    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
+    container:
+      image: python:3.12-slim
+      volumes:
+        - roro9stack-pio:/pio
+    env:
+      PLATFORMIO_CORE_DIR: /pio
+      RORO_NO_DOCKER: 1
+      SDK_MARK: /pio/packages/framework-arduinoespressif32-libs/.roro-sdkconfig.defaults
+      CCACHE_DIR: /pio/ci/ccache
+      CCACHE_MAXSIZE: 1G
+    steps:
+      - name: Tools
+        run: |
+          apt-get update -qq
+          apt-get install -y -qq --no-install-recommends git build-essential openssl ccache >/dev/null
+          mkdir -p /pio/ci
+          if [ ! -x /pio/ci/venv/bin/pio ]; then
+            python -m venv /pio/ci/venv
+            /pio/ci/venv/bin/pip install -q --no-cache-dir platformio gcovr
+          fi
+          ln -sf /pio/ci/venv/bin/pio /pio/ci/venv/bin/gcovr /usr/local/bin/
+          pio --version; df -h /pio | tail -1; du -sh /pio/ci/* 2>/dev/null || true
+          # The build cache only grows: start it again past 3 GB (a full set of objects is 160 MB, and each run adds about 40).
+          if [ "$(du -sm /pio/ci/build-cache 2>/dev/null | cut -f1)" -gt 3072 ] 2>/dev/null; then rm -rf /pio/ci/build-cache; fi
+
+      - name: Check out
+        run: |
+          find . -mindepth 1 -maxdepth 1 -exec rm -rf {} +
+          git config --global --add safe.directory '*'
+          git init -q .
+          git remote add origin "${{ github.server_url }}/${{ github.repository }}.git"
+          git fetch -q --tags origin '+refs/heads/*:refs/remotes/origin/*' '+refs/pull/*/head:refs/remotes/pull/*'
+          git checkout -q --detach "${{ github.sha }}"
+          git describe --tags --always
+
+      - name: Host tests, and their coverage of lib/
+        if: github.event_name != 'workflow_dispatch'
+        run: |
+          export PATH="/usr/lib/ccache:$PATH"  # gcc and g++ through ccache
+          scripts/coverage.sh
+          ccache -s | grep -E 'Hits|Misses' | head -2
+
+      # A pull request only: a tag's firmware is built once, by the release step below.
+      - name: The firmware
+        if: github.event_name == 'pull_request'
+        env:
+          PLATFORMIO_BUILD_CACHE_DIR: /pio/ci/build-cache
+        run: |
+          [ ! -f "$SDK_MARK" ] || cp "$SDK_MARK" sdkconfig.defaults
+          scripts/ci.sh builds
+          cp sdkconfig.defaults "$SDK_MARK"  # what the framework in the volume is rebuilt with, now
+
+      # The README's badges are files on a branch of their own, replaced at each push to main and
+      # at each tag (the release badge says which tag is the latest)
+      - name: Publish the badges
+        if: github.event_name == 'push' && (github.ref == 'refs/heads/main' || github.ref_type == 'tag')
+        env:
+          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
+        run: |
+          rm -rf /tmp/badges && mkdir /tmp/badges
+          cp .pio/coverage/coverage.svg .pio/coverage/summary.json /tmp/badges/
+          scripts/coverage_badge.py --plain release "$(git describe --tags --abbrev=0)" /tmp/badges/release.svg
+          cd /tmp/badges
+          git init -q -b badges .
+          git add .
+          git -c user.name="roro9stack CI" -c user.email="ci@git.twis.la" commit -q -m "Coverage of ${{ github.ref_name }} at ${{ github.sha }}"
+          git push -q --force "$(echo "${{ github.server_url }}" | sed "s#://#://ci:${GITEA_TOKEN}@#")/${{ github.repository }}.git" badges
+
+      - name: Which release
+        id: release
+        run: |
+          if [ "${{ github.event_name }}" = workflow_dispatch ]; then
+            echo "tag=${{ inputs.tag }}" >> "$GITHUB_OUTPUT"
+          elif [ "${{ github.ref_type }}" = tag ]; then
+            echo "tag=${{ github.ref_name }}" >> "$GITHUB_OUTPUT"
+          fi
+
+      - name: Build and sign the release
+        if: steps.release.outputs.tag != ''
+        env:
+          OTA_SIGNING_KEY: ${{ secrets.OTA_SIGNING_KEY }}
+        run: |
+          # The sources of the tag in a clone of their own; the tools are this commit's.
+          rm -rf /tmp/release-src dist
+          git clone -q . /tmp/release-src
+          git -C /tmp/release-src checkout -q --detach "refs/tags/${{ steps.release.outputs.tag }}"
+          # The key exists as a file only while this step runs, in a container that goes with the job.
+          umask 077
+          export RORO_OTA_KEY="$(mktemp)"
+          trap 'rm -f "$RORO_OTA_KEY"' EXIT
+          printf '%s\n' "$OTA_SIGNING_KEY" > "$RORO_OTA_KEY"
+          umask 022
+          # The framework rebuilt with our settings is reused if it matches (the platform checks);
+          # the release's own sources are compiled from nothing, with no build cache.
+          [ ! -f "$SDK_MARK" ] || cp "$SDK_MARK" /tmp/release-src/sdkconfig.defaults
+          scripts/release_build.sh /tmp/release-src dist
+          # An old tag has no SDK settings of its own, and no sdkconfig.defaults afterwards: nothing to mark.
+          [ ! -f /tmp/release-src/sdkconfig.defaults ] || [ ! -d "$(dirname "$SDK_MARK")" ] || cp /tmp/release-src/sdkconfig.defaults "$SDK_MARK"
+
+      - name: Publish the release
+        if: steps.release.outputs.tag != ''
+        env:
+          GITEA_API: ${{ github.server_url }}/api/v1
+          GITEA_REPO: ${{ github.repository }}
+          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
+        run: scripts/release_publish.py dist
+
+      # The site names the latest release on its home page and lists them all on Downloads, both
+      # read when it is built: so it is rebuilt now (issue #79, as the Site workflow does).
+      - name: Refresh the site
+        if: steps.release.outputs.tag != ''
+        env:
+          SITE_DEPLOY_KEY: ${{ secrets.SITE_DEPLOY_KEY }}
+          SITE_DEPLOY_HOST: ${{ secrets.SITE_DEPLOY_HOST }}
+          SITE_DEPLOY_USER: ${{ secrets.SITE_DEPLOY_USER }}
+          SITE_DEPLOY_KNOWN_HOSTS: ${{ secrets.SITE_DEPLOY_KNOWN_HOSTS }}
+        run: scripts/site_refresh.sh

.gitea/workflows/site.yml

@@ -0,0 +1,66 @@
+# The project site (docs/milestones/W1.md): built with Zola to see that it builds and that its pages
+# are sound. After a push to main it is then published: the job asks the web server, over SSH, to
+# pull main and rebuild (issue #79, scripts/site_refresh.sh). The key it holds can run that one
+# command there and nothing else; the server, the user and the keys are secrets, not in this file.
+#
+# It runs when the site, or a document the site is built from, changes (a pull request, or a push to
+# main); the firmware workflow (ci.yml) skips a change that touches only these files. A change that
+# touches both runs both. src/main.cpp and lib/core/src/app_keys.h are here too: the site's command
+# reference and its key tables are generated from them, and this job checks that they are still current.
+name: Site
+on:
+  push:
+    branches: [main]
+    paths: ['site/**', 'docs/**', 'README.md', 'CONTEXT.md', 'src/main.cpp', 'lib/core/src/app_keys.h', '.gitea/workflows/site.yml', 'scripts/site_refresh.sh']
+  pull_request:
+    paths: ['site/**', 'docs/**', 'README.md', 'CONTEXT.md', 'src/main.cpp', 'lib/core/src/app_keys.h', '.gitea/workflows/site.yml', 'scripts/site_refresh.sh']
+
+jobs:
+  build:
+    runs-on: ubuntu
+    # A pull request from a fork would run someone else's code on our runner: not without us.
+    if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository
+    container:
+      image: python:3.12-slim
+    steps:
+      - name: Tools
+        run: |
+          apt-get update -qq
+          apt-get install -y -qq --no-install-recommends git ca-certificates curl >/dev/null
+          # Zola, pinned by its checksum.
+          curl -fsSL -o /tmp/zola.tgz https://github.com/getzola/zola/releases/download/v0.22.0/zola-v0.22.0-x86_64-unknown-linux-gnu.tar.gz
+          echo "f1d491f8956b94384c27d75cb6b2bf60d3916d1ade9564bcbfe7c03f0258aebf  /tmp/zola.tgz" | sha256sum -c -
+          tar xzf /tmp/zola.tgz -C /usr/local/bin zola
+          zola --version
+
+      - name: Check out
+        run: |
+          find . -mindepth 1 -maxdepth 1 -exec rm -rf {} +
+          git config --global --add safe.directory '*'
+          git init -q .
+          git remote add origin "${{ github.server_url }}/${{ github.repository }}.git"
+          git fetch -q origin '+refs/heads/*:refs/remotes/origin/*' '+refs/pull/*/head:refs/remotes/pull/*'
+          git checkout -q --detach "${{ github.sha }}"
+
+      - name: The generated developer pages are current
+        run: python3 site/tools/gen_dev_docs.py --check
+
+      - name: Build the site
+        run: |
+          cd site
+          zola check --skip-external-links
+          zola build --output-dir /tmp/site-out
+
+      - name: Check the pages
+        run: python3 site/tools/check_site.py /tmp/site-out
+
+      # Only what has been merged, and only once it has built and passed the checks above. A pull
+      # request never gets here, and the secrets are given to this step alone.
+      - name: Publish the site
+        if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+        env:
+          SITE_DEPLOY_KEY: ${{ secrets.SITE_DEPLOY_KEY }}
+          SITE_DEPLOY_HOST: ${{ secrets.SITE_DEPLOY_HOST }}
+          SITE_DEPLOY_USER: ${{ secrets.SITE_DEPLOY_USER }}
+          SITE_DEPLOY_KNOWN_HOSTS: ${{ secrets.SITE_DEPLOY_KNOWN_HOSTS }}
+        run: scripts/site_refresh.sh

.gitignore

@@ -4,3 +4,14 @@
 
 # Private signing keys never belong in the repository (ADR 0003)
 *key.pem
+
+# Generated by pioarduino's hybrid compile from custom_sdkconfig (platformio.ini)
+.dummy/
+managed_components/
+sdkconfig.*
+
+# The built site (site/config.toml sends it here)
+/public/
+
+# The version, written by scripts/version.py before each build
+lib/version/src/version_generated.h

CONTEXT.md

@@ -20,6 +20,10 @@ _Avoid_: daemon, task, driver
 The Service that keeps the device participating in a mesh network at all times: receiving, relaying, and sending on behalf of Apps.
 _Avoid_: radio, LoRa app
 
+**Radio Service**:
+The Service that owns the LoRa radio on the Cap: it configures it, shares the SPI bus with the SD card, and receives in the background. The LoRa Scanner uses it directly; the Mesh Service sits on top of it.
+_Avoid_: LoRa driver, modem
+
 **Mesh Protocol**:
 One on-air language the Mesh Service can speak (Meshtastic first; others may follow). The Mesh Service speaks Mesh Protocols; Apps don't.
 _Avoid_: stack, mode
@@ -40,16 +44,36 @@ _Avoid_: DM (in docs), private message
 Rebroadcasting another Node's packet so it travels further across the mesh.
 _Avoid_: forwarding, repeating
 
+**Capsule**:
+A Gemini site: everything served by one host on Geminispace.
+_Avoid_: site, server (when the content is meant)
+
+**Saved Page**:
+A Gemini page kept on the SD card to read offline, with the URL it came from and when it was saved. Kept until the user deletes it; Storage Clean-up never offers it.
+_Avoid_: cache, download (a download is a non-text file saved from Gemini)
+
+**GNSS Service**:
+The Service that owns the GNSS receiver on the Cap: it reads its NMEA sentences in the background and holds the current Fix, position, time and satellites.
+_Avoid_: GPS (GPS is one constellation among several)
+
+**Fix**:
+What the receiver currently knows: none, 2D (position without altitude) or 3D (with altitude), from how many satellites, at what HDOP.
+_Avoid_: lock, signal
+
+**Track**:
+A route recorded from GNSS positions to a GPX file on the SD card, started and stopped by the user.
+_Avoid_: trace, log (a Log is recorded on its own)
+
 **Wi-Fi Service**:
 The Service that owns the Wi-Fi radio. It's always in exactly one mode: *Off*, *Connected* (joined to a Saved Network) or *Monitoring* (passively observing). When Wi-Fi is enabled in Settings, it stays Connected whenever a Saved Network is in range. It goes Monitoring only while Wi-Fi Tools needs it, then reconnects.
 _Avoid_: network manager
 
 **Saved Network**:
-A Wi-Fi network the device may join on its own (name, password). When several are in range, the strongest wins.
+A Wi-Fi network the device may join on its own: its name, its password, and how it gets its address, *Automatic* (DHCP) or *Fixed* (an address, a prefix and an optional gateway typed in Settings). When several are in range, the strongest wins.
 _Avoid_: profile, known network
 
 **IRC Service**:
-The Service that keeps the IRC connection alive in the background once the IRC App has started it, until the user disconnects. It reconnects after drops, and pauses while the Wi-Fi Service is Monitoring. It does not start by itself after a reboot.
+The Service that keeps the IRC connection alive in the background once the IRC App has started it, until the user stops it (`/quit`, or `irc stop` on the console). Once stopped by hand, opening the App again doesn't reconnect; typing a line does. It reconnects after drops, and pauses while the Wi-Fi Service is Monitoring. It does not start by itself after a reboot.
 _Avoid_: IRC client (that's the App)
 
 **Buffer**:
@@ -82,6 +106,14 @@ The regulatory band plan the device transmits under (here EU868). It sets the al
 **Duty Cycle Budget**:
 The share of airtime the Region allows this device to transmit. When it's used up, outgoing traffic waits.
 
+**Shell**:
+The App that runs the console's commands on the device itself, and shows what the console prints. Trusted like the USB port, not like the network.
+_Avoid_: terminal, command line, REPL
+
+**Help panel**:
+The list of the keys that work on the screen you are on, opened with Fn+h anywhere (or `?` outside Text Entry). Each App answers for its current state; no screen names keys any other way, except the first-start Setup.
+_Avoid_: hints, cheat sheet, shortcuts bar
+
 **Text Entry**:
 When an App is editing text. During Text Entry, `;` `.` `,` `/` type their characters and Fn makes them arrows. Otherwise they are arrows on their own.
 _Avoid_: edit mode, insert mode
@@ -99,13 +131,28 @@ Data the user explicitly starts recording, such as Wi-Fi packet captures and LoR
 _Avoid_: dump, log
 
 **Storage Warning**:
-The Notification raised once per boot when the SD card passes 80% full. Selecting it opens Storage Clean-up.
+The Notification raised once per boot when the SD card passes 80% full. It points at the Storage App, where Maintenance holds Storage Clean-up.
 
 **Storage Clean-up**:
-The screen where the user deletes old Logs and Captures by category and age, with a preview of the space freed. Notes are never offered for deletion.
+The screen where the user deletes old Logs and Captures by category and age, with a preview of the space freed. Notes are never offered for deletion. It lives in the Storage App, under Maintenance.
+
+**Note**:
+A plain text file in `/notes`, written on the device in the Notes App. Listed by its first line. Saved without being asked; never offered by Storage Clean-up.
+_Avoid_: memo, document
+
+**Storage App**:
+The App that browses the SD card: folders and files, a clipboard for one item at a time (copy, cut, paste), rename, delete, new folder, and a viewer for each kind of file the firmware writes. The top-level folders, `/gemini/cache` and files being written are read-only.
+_Avoid_: file manager, Files, explorer
+
+**Maintenance**:
+The part of the Storage App that deletes in bulk: the card's usage, Storage Clean-up and erasing the card. Reached through a warning.
+_Avoid_: Settings > Storage
 
 **Firmware Update**:
-Installing a new firmware image without a USB cable: pushed over Wi-Fi from the developer's PC, or read from the SD card.
+Installing a new firmware image without a USB cable: pushed over Wi-Fi from the developer's PC, read from the SD card, or downloaded from the project's Gitea **Release**.
+
+**Release**:
+A tag `v*` on the project's Gitea with a signed **Update File**, a factory image for USB, the ELF to decode crashes and checksums, built and published by CI. The device reads them to look for updates.
 _Avoid_: flash, upgrade (alone)
 
 **Update File**:
@@ -121,16 +168,12 @@ Returning automatically to the previous firmware when new firmware resets or cra
 _Avoid_: revert, downgrade (a downgrade is installing an older version on purpose)
 
 **Safe Mode**:
-What the firmware starts instead of everything else after 3 crash restarts in a row: Wi-Fi and Firmware Updates (and the Debug Console in a Debug Build), so it can be fixed without a cable. A normal restart leaves it.
+What the firmware starts instead of everything else after 3 crash restarts in a row: Wi-Fi and Firmware Updates (and the Debug Console if it's switched on), so it can be fixed without a cable. A normal restart leaves it.
 _Avoid_: recovery mode, failsafe
 
-**Debug Build**:
-A firmware built with the remote debugging aids compiled in (`+debug` in its version). Release builds have none of them.
-_Avoid_: dev build, test build (a test build is one made to fail on purpose, such as a crashing update)
-
 **Debug Console**:
-The console of a Debug Build over Wi-Fi: live log lines and the serial commands, behind a token.
-_Avoid_: telnet, remote shell
+The console over Wi-Fi, in every firmware but off until switched on in Settings: live log lines and the serial commands, for whoever holds the device's token.
+_Avoid_: telnet, remote shell, Debug Build (there is one firmware)
 
 ## Relationships
 
@@ -139,6 +182,7 @@ _Avoid_: telnet, remote shell
 - The **Mesh Service** speaks one or more **Mesh Protocols** and tracks the known **Nodes**.
 - The **Wi-Fi Service** is either Connected or Monitoring, never both. Monitoring pauses the **IRC Service**, which reconnects and rejoins its **Buffers** afterwards.
 - **Services** raise **Notifications**; the **Status Bar** summarises **Service** state.
+- The **Radio Service** owns the radio; the **Mesh Service** and the LoRa Scanner use it.
 - A **Sweep** pauses the **Mesh Service**; a **Sniffer** does not.
 - Every transmission is bounded by the **Region** and its **Duty Cycle Budget**.
 - Past 90% SD usage, **Logs** stop being written; the remaining space is kept for **Captures**. Nothing is deleted without the user's confirmation.

README.md

@@ -1,11 +1,17 @@
 # roro9stack
 
+[![CI](https://git.twis.la/twisla/roro9stack/actions/workflows/ci.yml/badge.svg?branch=main)](https://git.twis.la/twisla/roro9stack/actions?workflow=ci.yml) [![Coverage of lib/ by the host tests](https://git.twis.la/twisla/roro9stack/raw/branch/badges/coverage.svg)](#build-and-test-local-ci) [![Latest release](https://git.twis.la/twisla/roro9stack/raw/branch/badges/release.svg)](https://git.twis.la/twisla/roro9stack/releases/latest)
+
 A multi-app firmware for the **M5Stack Cardputer ADV** with the **Cap LoRa-1262**. It's a Meshtastic-compatible mesh messenger, plus Wi-Fi tools, IRC, GNSS and more. Licensed GPL-3.0.
 
 - Domain language: [CONTEXT.md](CONTEXT.md)
 - Decisions: [docs/adr/](docs/adr/)
 - Milestones: [docs/milestones/](docs/milestones/)
 
+## On the device: one key
+
+**Fn+h, on any screen, lists the keys that work there** (`?` does the same outside a text field). No screen names its keys itself (docs/milestones/U1.md). Every screen's keys are one table in `lib/core/src/app_keys.h`: the help panel shows the table of the state an App is in, and the website's key tables are generated from the same file.
+
 ## Requirements
 
 Only **Docker** is needed. PlatformIO and the ESP32 toolchain run inside a container, and are cached in the `roro9stack-pio` Docker volume. The first build downloads about 1 GB and takes a few minutes.
@@ -18,6 +24,27 @@ scripts/ci.sh
 
 This runs the host-side unit tests (`test/`, `native` environment), then builds the firmware. The output is `.pio/build/cardputer-adv/firmware.factory.bin`.
 
+`scripts/coverage.sh` runs the same tests with coverage counters and writes a line-by-line report to `.pio/coverage/index.html`. The badge above is its figure for `main`: the share of the lines of `lib/` that the host tests run. `lib/` is the logic that compiles on a PC; `lib/SD` (the card's driver) and `src/` (the Apps, the Services, everything that needs the device) have no host tests and aren't in that figure.
+
+The framework is rebuilt with the TLS settings in `platformio.ini` (`custom_sdkconfig`, ADR 0006), so the first build after a fresh checkout takes about 6 minutes; later builds take about 15 seconds when little has changed. The platform knows the framework is already rebuilt by `sdkconfig.defaults` in the project folder, which it writes and git ignores: delete it and the next build rebuilds the framework. CI keeps that file, a build cache and ccache in its volume (docs/milestones/R1.md).
+
+## CI and releases
+
+Gitea Actions (`.gitea/workflows/ci.yml`, docs/milestones/R1.md) runs the host tests on every push to `main`, and on a pull request also builds the firmware: changes reach `main` through pull requests. Pushing a tag `v*` runs all of it and publishes a release on Gitea with:
+
+- `roro9stack-<version>.ota`, the signed Update File;
+- `roro9stack-<version>-factory.bin`, the whole flash image for a first install over USB;
+- `roro9stack-<version>.elf.gz`, to decode crash reports from that build;
+- `SHA256SUMS`.
+
+CI signs with the project's key, held as a repository secret (ADR 0008). There is one firmware: the Debug Console is in every build, switched off until its owner switches it on (ADR 0010).
+
+`scripts/ota_verify.py <file.ota>` checks an Update File on a PC the way a device does. `scripts/release_build.sh` and `scripts/release_publish.py` are what the workflow runs; they work the same by hand.
+
+## The website
+
+The project's site, **roro9stack.net**, is built from `site/` with Zola (see `site/README.md`): the home page, an Install page that flashes a Cardputer from the browser, and every release. Changes under `site/`, `docs/`, `README.md` and `CONTEXT.md` run only the site's CI job, not the firmware tests and builds.
+
 ## Flash
 
 1. Connect the Cardputer by USB-C.
@@ -50,7 +77,88 @@ The device shows the push address in **Settings → Firmware**. It installs a co
 
 To install from the SD card instead, copy the `.ota` file from `.pio/build/cardputer-adv/` into `/updates` on the card, then use **Settings → Firmware**. With the Cardputer on USB, the card can stay in: `scripts/sd_put.sh <file.ota>` sends it over the serial console into `/updates` (about 30 s for 1.6 MB, checked with SHA-256 before it's renamed into place; `SD_PUT_DEBUG=1` shows the console while it runs).
 
-**The private key** lives in `~/.config/roro9stack/ota-key.pem` and must never be committed. If it's lost, generate a new pair and flash once over USB.
+**The private key** lives in `~/.config/roro9stack/ota-key.pem` and must never be committed. If it's lost, generate a new pair and flash once over USB. (CI signs releases with a copy kept as a repository secret, ADR 0008.)
+
+### Updates from Gitea
+
+With no PC and no card, the device can install the project's releases itself (docs/milestones/R1.md). In **Settings → Firmware**:
+
+- **Latest release** checks the server (Enter, or `c`) and says `v0.11.0 (new)` or `(current)`. Enter again opens the release: its version, date, size and the tag's message, with **Install** when it's newer. The download goes straight into the inactive slot, so no card is needed; the signature is checked after the first 160 bytes, before anything is written, and the image's hash at the end. The new firmware then runs on Probation as for any update.
+- **Older releases** lists the last ten, newest first. Opening an older one offers to go back to it, with a different question.
+- **Settings → Check for updates** (on by default): once a day, with Wi-Fi up and the clock set, the device looks at the latest release and says `v0.11.0 is out: see Settings > Firmware`, once per version. It installs nothing by itself, and doesn't announce a version that already failed and rolled back on this device.
+
+The connection is checked against the two ISRG roots Let's Encrypt chains end in (ADR 0009), not the usual bundle of about 130 authorities. Whatever the connection, the Update File's own signature is what decides what gets installed.
+
+**IRC steps aside.** A secure connection takes about 52 KB of memory at its peak, and IRC's own takes 40 KB of the 107 KB there is. A check or an install you ask for makes IRC disconnect for the few seconds it takes and reconnect afterwards. The daily check never does that: with IRC connected it waits for a moment when IRC isn't, so while IRC stays connected for days it doesn't run, and **Latest release** is the way to check.
+
+**There is no separate Debug Build** any more (ADR 0010): every firmware installs releases, and the Debug Console is a setting, which an update leaves as it was.
+
+## Networks without DHCP
+
+Each Saved Network gets its address automatically (DHCP) or has a Fixed one (docs/milestones/S1.md): in Settings > Wi-Fi, Enter on a network opens its page, where "IP address" switches between Automatic and Fixed, with an address, a prefix length (24 is 255.255.255.0) and an optional gateway. Switching to Fixed starts from what the network is giving the device at that moment. The setting is checked and applied when you leave the page. IPv4 only.
+
+"DNS and NTP" on the same screen holds two DNS servers (9.9.9.9 and 1.1.1.1 by default), used on Fixed networks, or on every network with "Always use my DNS"; and two NTP servers (pool.ntp.org and time.cloudflare.com), used after any the network's DHCP offers. Enter on "Status" shows what's in use and where each value came from.
+
+## System
+
+The System App (docs/milestones/S1.md) shows what the device is doing, live and read-only, in any build. Tab moves between five views:
+
+- **Overview:** each core's load, free memory, network traffic, battery, uptime and chip temperature, and both cores' load over the last two minutes.
+- **Tasks:** every FreeRTOS task with its core, its share of a core over the last second, and the least stack it ever had left (in the warning colour under 512 bytes). `s` sorts by share, stack or name.
+- **Memory:** free heap, the lowest since boot and the largest free block, with two minutes of free heap drawn against the three memory floors (55, 40 and 20 KB).
+- **Network:** the connection, then for IRC, Gemini, the Debug Console and Firmware Updates the bytes read and written since boot and what's moving now. For TLS connections these are the bytes the service sees, without the encryption overhead.
+- **System:** what `info` prints, plus the battery, the SD card with its write faults, the radio and the GNSS receiver.
+
+It samples once a second and keeps its history only while it's open.
+
+## Gemini
+
+The Gemini App browses Geminispace (docs/milestones/G1.md): Tab and Shift+Tab pick a link, Enter follows it, Back returns (to where the page was scrolled), Space pages down, `g` types an address. Certificates are trusted on first use; a changed one stops the page and asks.
+
+On a page, `b` bookmarks it, `s` saves it to the SD card to read offline (a non-text file goes to `/gemini/downloads/`), `S` saves it with the pages it links to on the same capsule (up to 30). The start page lists bookmarks and Saved Pages; inside a Saved Page, `r` refreshes it and `d` deletes it. With a card, every page streams through `/gemini/cache/` so a large one arrives whole even with IRC connected; what doesn't fit in memory stays on the card.
+
+## LoRa Scanner
+
+The LoRa Scanner (docs/milestones/M3.md) listens with the Cap's radio and **never transmits**. The Sniffer lists what it hears, newest first: time, RSSI, SNR, and for Meshtastic packets the sender and receiver (their last 4 hex digits) and hops. Enter shows a packet's details: the Meshtastic header (which is never encrypted) and a hex dump. `p` picks one of the 7 Meshtastic presets allowed in EU868 (LongFast by default), `c` starts or stops a Capture: a pcap file with LoRaTap headers in `/captures/lora/`, for Wireshark. A Capture keeps recording with the App closed; otherwise the radio sleeps when the App isn't open. Tab switches to **Sweep**: the signal strength across 863–870 MHz in 100 kHz steps, as bars with peak hold and a waterfall, with the Sniffer's frequency marked; the Sniffer is paused meanwhile and picks up where it was. The GNSS receiver on the same Cap raises the radio's noise floor by 8 dB while it runs: Settings > "Pause GNSS for LoRa" (off by default) puts it in standby while the radio listens, except during a Track. The Status Bar shows `L` while the radio listens (bright for a moment on each packet), `SW` while sweeping, and `CAP` while capturing.
+
+## Storage
+
+The Storage App (docs/milestones/F1.md) shows what's on the SD card: each folder's entries with their size and date, folders first. Enter opens a folder, Back goes up; `s` sorts by name, date or size. It works on one item at a time, with a clipboard:
+
+| Key | Does |
+|---|---|
+| `c` / `x` | Copies or cuts the selected file or folder; the footer shows what `v` would paste |
+| `v` | Pastes it into the folder shown. A copy next to its original is named `name (2).txt`; anything in the way is asked about first |
+| `r` | Renames |
+| `d` | Deletes, after saying what's inside: "Delete saved and its 42 files (1.2 MB)?" |
+| `n` | Makes a folder |
+| `i` | Details: type, exact size, date, and why an item is read-only if it is |
+
+A copy runs in the background of the card (about 400 KB a second) in short turns, so Logs and Captures keep being written; it shows its progress, Back cancels it and takes back what was copied, and each file's size is checked afterwards. Three things can't be changed: the top-level folders the firmware keeps its files in (what's inside them can), `/gemini/cache`, and any file being written right now (today's IRC Logs, a Track or a Capture being recorded). The App says why when it refuses. A folder with more than 256 entries shows the first 256 by name and says so.
+
+Enter on a file opens it by type; Tab switches to the same file as a hex dump or as text:
+
+- **Text** (`.txt`, `.log`, `.gmi`, `.csv`, and anything that looks like text): only the screen's worth is read from the card, so a file of any size opens at once. Logs open at the end. Up and Down move a line, Left and Right a page, `t` and `b` go to the top and the end, `e` edits it (up to 16 KB, see Notes).
+- **Captures** (`.pcap`): the packets as the LoRa Scanner lists them; Enter shows one with its Meshtastic header and bytes.
+- **Tracks** (`.gpx`): the number of points, the start, the duration and the distance.
+- **Update Files** (`.ota`): the version, and whether the file would install: it's checked as an install checks it (signature and contents) without writing anything. Enter then installs it.
+- **Anything else:** a hex dump.
+
+At the top of the card the last row, **Maintenance** (also `m`), holds the card's usage, Storage Clean-up and "Erase SD card", behind a warning: those delete for good. It replaces Settings > Storage.
+
+## Notes
+
+The Notes App (docs/milestones/F1.md) keeps plain text notes in `/notes` on the SD card. The list shows each note's first line and its date, newest first; `s` switches to by file name. `n` starts a note, Enter opens one, `r` renames its file, `d` deletes it after asking.
+
+In the editor, type. Enter starts a line, Del deletes backwards, Fn with the arrows moves the cursor through the wrapped text, Ctrl+A and Ctrl+E go to the start and the end of the line, Tab types two spaces, and the Compose Key gives accents as everywhere. **There's no save key:** the note is written five seconds after the last key, on Back, on leaving the App, when the screen turns off and before the device powers off. The top line says "typing" or "saved". Each save writes a temporary file and then puts it in the note's place, so a power cut costs a few seconds of typing and never the note; if a save was cut short, opening the note offers its copy back.
+
+A new note has no file until something is typed; its file is then named after its first line (`shopping-list.txt`), or `note-<date>-<time>.txt`.
+
+A note holds up to 16 KB while it's edited. A bigger text file opens read-only in the Storage App (editing any size is issue #47). The Storage App's text viewer has `e` to edit a file with the same editor, anywhere on the card, unless the file is read-only.
+
+## Shell
+
+The Shell App (docs/milestones/S1.md) runs the commands below on the device's own screen and keyboard: no PC, no cable, no Wi-Fi. **It shows the replies to its own commands and nothing else**: the console knows who each line is printed for, so a listing read by another task a moment later is still the Shell's, and what USB or the Debug Console asked for is not. Ctrl+b shows everything instead. Tab completes a command word by word (`lora st` gives `lora status`) and, past it, a path on the SD card (`ls /no` gives `ls /notes/`), Fn with up and down recalls earlier lines, Alt with up and down scrolls back. **An App's name with a capital opens it** (`Notes`, `Irc`, `Wifi`, `Gnss`, `Gemini`, `Lora`, `Storage`, `System`, `Settings`), from the consoles too. `rm` is Unix's, with a question: a folder needs `-r`; a file, or a folder with something in it, is asked about unless `-f` (`rm -rf`); an empty folder goes without a word. `*` and `?` in a name stand for several files (`rm /notes/*.txt` asks once, with the count; 64 at most). `clear` empties the screen and `quit` leaves. It is trusted like the USB port: `debug on` and `debug token` work from it. It uses about 7 KB of memory while it is open, and none otherwise.
 
 ## Development aids
 
@@ -59,40 +167,72 @@ To install from the SD card instead, copy the `.ota` file from `.pio/build/cardp
 | Command | Effect |
 |---|---|
 | `burst` | Publishes 5 Notifications at once |
-| `key up\|down\|left\|right\|select\|back\|home`, or `key <char>` | Injects a key press |
+| `key up\|down\|left\|right\|select\|back\|home\|del\|tab\|space\|help`, or `key <char>` | Injects a key press (`help` is Fn+h: the keys of the screen that is showing) |
 | `sound on` / `sound off` | Toggles the Sound setting (beep + LED) |
 | `short` / `normal` | Screen timeouts 5 s / 10 s, or 30 s / 60 s |
 | `wifi add <ssid><TAB><password>` | Adds a Saved Network (so credentials stay out of the repo) |
+| `wifi ip <ssid> dhcp` / `wifi ip <ssid> <address>/<prefix> [gateway]` | A Saved Network's IP setting: Automatic, or Fixed. Add `try <seconds>` to go back to the previous setting unless `wifi ip keep` follows |
+| `wifi dns <a> [b]` / `wifi dns always on\|off` / `wifi ntp <a> [b]` | DNS servers (used on Fixed networks, or always), and NTP servers |
 | `log <text>` | Appends a line to a test IRC Log (`/irc/dev/#test/<date>.log`) |
+| `sd card` | What the SD card says it is: type, size, and its identity register (maker, name, revision, serial, date) |
 | `sd list` | Lists the files of each Storage Clean-up category |
+| `sd fill <folder> <count>` | Makes that many small files in a folder, to test a crowded one |
 | `cat <path>` | Prints the first ~1.2 KB of a file on the SD card |
 | `irc start` | Starts the IRC Service (normally done by opening the IRC App) |
+| `irc stop` | Stops it, as `/quit` does: QUIT if connected, no more retries, and the App stays disconnected until you type |
+| `gemini get <url>` | Fetches a Gemini page and prints its header, size, certificate fingerprint and heap use |
+| `gemini trust <host> <port> <sha256>` | Pins a certificate by hand (the Gemini App asks when one changes) |
 | `irc say <buffer> <text>` | Types into a Buffer, commands included (`irc say 0 /join #test`) |
 | `irc dump` | Prints IRC status, memory, and the last lines of each Buffer |
-| `wifi status` | Prints Wi-Fi state, network, signal, clock and free heap |
-| `info` | Firmware, uptime, last start reason, memory, Wi-Fi, and both app slots with their versions and OTA states |
-| `tasks` | FreeRTOS tasks: state, priority, lowest free stack, CPU share |
+| `wifi status` | Prints Wi-Fi state, network, signal, clock and free heap, then the address, gateway, DNS and NTP servers in use and where each came from |
+| `info` | Firmware, uptime, last start reason, memory, Wi-Fi, the SD card and its write faults since boot, **which App is in front**, and both app slots with their versions and OTA states |
+| `Notes`, `Irc`, `Wifi`, `Gnss`, `Gemini`, `Lora`, `Storage`, `Shell`, `System`, `Settings` | Opens that App: a capital letter is an App, not a command |
+| `tasks` | FreeRTOS tasks over the next second: state, priority, lowest free stack, share of a core, each core's load, and how many passes the main loop made |
+| `net` | Bytes each network service has read and written since boot |
 | `reboot` / `boot other` | Restart, or restart into the other app slot (a manual Rollback) |
 | `log level <0-5>` | ESP-IDF log level |
-| `ls [folder]` / `rm <path>` | Lists a folder of the SD card, or deletes a file |
+| `ls [folder]` / `du <path>` | Lists a folder of the SD card with sizes and dates, or counts the files and bytes under a path |
+| `screenshot [seconds]` | The screen as a PNG in `/screenshots` on the card, now or after a pause to get to the screen you want (240 x 135, about 33 KB). Over the Debug Console a bare `screenshot` sends the screen to the PC instead |
+| `cp [-f] <from> <to>` / `mv [-f] <from> <to>` / `rm [-r] [-f] <path>` / `mkdir <path>` / `cancel` | What the Storage App does, with its rules: copy (folders too), move or rename, delete (`rm -r` for a folder and what's in it, as Unix has it), new folder. `-f` replaces a file that's in the way; `*` and `?` in the last part of a path (`ls`, `du`, `rm`, `cp`, `mv`) run the command for each name matched, 64 at most; a tab separates paths that hold spaces; `cancel` stops a copy or a delete |
 | `install <path>` | Update from SD with that `.ota` file, as Settings → Firmware does |
+| `update check` / `update list` / `update status` / `update install <tag>` | The project's releases on Gitea: look at the latest, list the last ten, say what's known, or download and install one |
+| `update pretend <version>` / `update probe <host>` / `update damage cut\|flip <n>` / `update daily` | Pretend to run another version (so a release counts as an update), see whether a server's certificate is accepted, cut or damage the next download, run the daily check again |
+| `lora probe` | Finds the radio: chip, oscillator, antenna switch, DIO1 interrupt, noise floor |
+| `lora status` | Radio settings, who's listening, packet and error counters, noise floor, task stack |
+| `lora rx on` / `lora rx off` | Listens and prints each packet on the console |
+| `lora preset <name>` / `lora custom <MHz> <BW kHz> <SF> <CR> <sync hex> [preamble]` | Receive settings: a Meshtastic preset, or anything else (`lora custom 868.1 125 7 5 34 8` for LoRaWAN) |
+| `lora capture start` / `lora capture stop` | A LoRa Capture, as `c` in the App |
+| `lora sweep on [from MHz] [to MHz] [step kHz]` / `lora sweep off` / `lora sweep dump` | Sweep a band (863 870 100 by default), with a summary every 2 s (floor, strongest, peaks), or print the latest pass |
+| `gnss quiet on` / `gnss quiet off` | The "Pause GNSS for LoRa" setting |
+| `gnss status` / `gnss restart` | The receiver's state, and a restart of it |
+| `gnss track start` / `gnss track stop` | A Track, as `r` in the GNSS App (the reason is printed if it can't start) |
+| `gnss nmea on` / `gnss nmea off` | Prints each NMEA sentence the receiver sends, as `nmea: …` |
+| `gnss send <sentence>` | Sends a sentence to the receiver, without the `$` and the checksum (it adds them) |
+| `lora noise test [gnss\|quiet]` / `lora noise report` | Sweep under one changed condition at a time to find what raises the noise floor (Wi-Fi goes off for a few seconds); then the result |
+| `lora inject <hex> [rssi] [snr]` | A packet into the Scanner as if received (nothing is sent) |
 | `crash` | The last crash: which firmware, why, task, PC and backtrace (from the core dump in flash) |
 | `coredump erase` | Forgets the core dump |
-| `crash abort` / `crash wdt` | Debug Builds: crash on purpose, or hang the main loop until the watchdog fires |
+| `loop spin on` / `loop spin off` | Make the main loop spin without resting, to compare load and radio noise |
+| `crash abort` / `crash wdt` | Crash on purpose, or hang the main loop until the watchdog fires |
+| `debug status` / `debug off [seconds]` | The Debug Console: whether it's on, has a token and a client; switch it off. With a number of seconds, it comes back by itself after that long |
+| `debug on` / `debug token <value>` / `debug token new` | USB serial only: switch it on (making a token if there's none), give it a token of 16 to 64 characters, or make a new one. The token is never printed |
 | `help` | Lists the commands |
 
 `scripts/flash.sh` stops a running serial log first, since it would hold the port.
 
-### Debug Builds and the Debug Console
+### The Debug Console
 
-`scripts/flash.sh --debug` (USB) or `scripts/flash.sh --debug --ota <ip>` (Wi-Fi) installs a Debug Build: the same firmware plus the Debug Console on TCP 2323 (ADR 0004). Then, with `RORO_OTA_HOST` set to the device's IP:
+Every firmware has the Debug Console (ADR 0010): the serial console over Wi-Fi, on TCP 2323. It is **off** until you switch it on in **Settings → Debug Console**, which also makes its token and shows it. With the device on USB, `scripts/flash.sh --debug` flashes it, switches the console on and gives it the token in `~/.config/roro9stack/debug-token`, so nothing has to be typed. Then, with `RORO_OTA_HOST` set to the device's IP:
 
 ```sh
 scripts/rdbg.py                 # interactive: the console backlog, live lines, and commands
 scripts/rdbg.py info            # one command and its reply
 scripts/rdbg.py -b tasks        # the same, after the backlog (boot messages and so on)
+scripts/rdbg.py -t K7QF-3M2X-9WBD-HT4P-6RNC info   # another device's token; or $RORO_DEBUG_TOKEN
 ```
 
+The token never crosses the network: the device sends a challenge and `rdbg.py` answers with its HMAC. Five wrong answers in a row close the console for a minute. `debug status` and `debug off` work from anywhere; `debug on`, `debug token <value>` and `debug token new` work over USB serial only.
+
 Every command above works there too, plus a few handled by the PC side or the console's own task:
 
 ```sh
@@ -106,6 +246,6 @@ scripts/rdbg.py get <card path> [file]    # from the SD card
 
 So a Firmware Update can also go `rdbg.py put roro9stack-….ota` then `rdbg.py install /updates/roro9stack-….ota`: the Update from SD path, without touching the device.
 
-Every build keeps its ELF in `.pio/elves/` (version and digest in the name) for that; `scripts/decode_backtrace.sh <version|digest> <addresses>` decodes any backtrace by hand.
+Every build keeps its ELF in `.pio/elves/` (version and digest in the name) for that, and `rdbg.py crash` fetches a release's ELF from Gitea when it isn't there; `scripts/decode_backtrace.sh <version|digest> <addresses>` decodes any backtrace by hand.
 
-After 3 crash restarts in a row the firmware starts in **Safe Mode** (ADR 0005): only Wi-Fi, Firmware Updates and the Debug Console, so a fix can be pushed as usual. `reboot` leaves it. The token is in `~/.config/roro9stack/debug-token`, made by the first build; keep developing on Debug Builds, so the firmware a Rollback returns to always has the console.
+After 3 crash restarts in a row the firmware starts in **Safe Mode** (ADR 0005): only Wi-Fi, Firmware Updates and, if it's switched on, the Debug Console, so a fix can be pushed as usual. `reboot` leaves it.

default_8MB.csv

@@ -0,0 +1,7 @@
+# Name,   Type, SubType, Offset,  Size, Flags
+nvs,      data, nvs,     0x9000,  0x5000,
+otadata,  data, ota,     0xe000,  0x2000,
+app0,     app,  ota_0,   0x10000, 0x330000,
+app1,     app,  ota_1,   0x340000,0x330000,
+spiffs,   data, spiffs,  0x670000,0x180000,
+coredump, data, coredump,0x7F0000,0x10000,

docker/Dockerfile

@@ -5,7 +5,7 @@ RUN apt-get update \
  && apt-get install -y --no-install-recommends git build-essential \
  && rm -rf /var/lib/apt/lists/*
 
-RUN pip install --no-cache-dir platformio
+RUN pip install --no-cache-dir platformio gcovr
 
 # Toolchains and libraries are cached in a named volume mounted here.
 RUN mkdir -p /pio && chmod 777 /pio

docs/adr/0001-own-firmware-speaking-meshtastic.md

@@ -9,3 +9,7 @@ A fork would give full compatibility on day one, but its architecture is built a
 - We accept partial Meshtastic compatibility at first: text on channels, Direct Messages, node list, position and relaying.
 - The phone-app (BLE) API and PKI-encrypted Direct Messages are deferred, and we must re-implement protocol details ourselves.
 - Multi-boot with stock Meshtastic via a launcher was rejected: it gives none of our own UX.
+
+## Note (2026-10-04, M2)
+
+NMEA is parsed by our own small, host-tested parser instead of TinyGPSPlus: the GNSS App's Sky view needs the satellite list (GSV) across several constellations, which TinyGPSPlus doesn't track. See docs/milestones/M2.md, Q66.

docs/adr/0004-debug-console-in-debug-builds.md

@@ -1,6 +1,8 @@
 # A Debug Console over Wi-Fi, in Debug Builds only
 
-The goal of Firmware Updates is to manage the device without a cable, and that includes finding out what went wrong. So a **Debug Build** (`cardputer-adv-debug`, `-DRORO_DEBUG`, version suffix `+debug`) adds a **Debug Console** on TCP 2323: the serial console, over Wi-Fi. A client sends a token as its first line, then gets the last 6 KB of console output (boot messages included), every new line live, and runs the same commands as the serial port, plus a few that only make sense remotely. ESP-IDF's own log lines are teed into it.
+**Superseded in part by [ADR 0010](0010-debug-console-in-every-build.md) (2026-10-06):** there is no Debug Build any more. The console is in every firmware, off until switched on, and its token belongs to the device, not to the build. What this record says about how the console works (the ring, commands on the main loop, binary commands on its own task, one client) still holds.
+
+The goal of Firmware Updates is to manage the device without a cable, and that includes finding out what went wrong. So a **Debug Build** (`cardputer-adv-debug`, `-DRORO_DEBUG`, version suffix `+debug`) adds a **Debug Console** on TCP 2323: the serial console, over Wi-Fi. A client sends a token as its first line, then gets the last 4 KB of console output (boot messages included), every new line live, and runs the same commands as the serial port, plus a few that only make sense remotely. ESP-IDF's own log lines are teed into it.
 
 It's compiled out of release builds entirely, rather than switched off by a setting. A console that runs commands is a remote control: in a release build, nothing listens.
 
@@ -9,7 +11,7 @@ It's compiled out of release builds entirely, rather than switched off by a sett
 - **Console, not Serial.** All human-readable output goes through `console`, which writes to the USB port and, in a Debug Build, to a ring buffer the Debug Console drains. Writes never wait for USB: a host that's attached but not reading used to stall the main loop for up to 2 s per line.
 - **Commands run on the main loop.** The socket lives on the Debug Console's own task, which only queues command lines. The main loop runs them, as it does serial commands, so they touch Apps and Services from the one task allowed to.
 - **The token** is 128 random bits in `~/.config/roro9stack/debug-token`, made by the first build and passed into the container. It's never committed; a Debug Build refuses to compile without one. Like the OTA key, it guards against the network, not against someone holding the device.
-- **One client at a time**, to keep memory flat (about 6 KB for the ring, 6 KB of task stack).
+- **One client at a time**, to keep memory flat (4 KB for the ring since M2, 6 KB of task stack).
 - **Binary commands are answered on the console's own task**, not queued: `get`/`put` (SD card files, run as one Storage Service job each so card access stays on the storage task, with TCP doing the flow control), `screenshot` (the 32 KB RGB332 frame the UI composes into, read as it stands, so it may tear), `coredump get` and `reset`. These keep working when the main loop is stuck. A failed `put` closes the connection, so the rest of the file is never read as commands.
 
 ## Keep a Debug Build in the fallback slot

docs/adr/0005-safe-mode-crash-reports-watchdog.md

@@ -1,9 +1,9 @@
 # Safe Mode, crash reports and a watched main loop, in every build
 
-Rollback protects against new firmware that fails Probation. It does nothing for firmware that was confirmed and crashes later: a corrupt setting, a server that sends something unexpected, a bug that takes an hour to show. Without a cable, such a device would restart forever. Three measures, in release and Debug Builds alike, keep it reachable:
+Rollback protects against new firmware that fails Probation. It does nothing for firmware that was confirmed and crashes later: a corrupt setting, a server that sends something unexpected, a bug that takes an hour to show. Without a cable, such a device would restart forever. Three measures, in every build, keep it reachable:
 
-- **Safe Mode.** The firmware counts starts that follow a crash (panic or watchdog) in NVS, first thing at boot. After 3 in a row, it starts only the clock, Wi-Fi, the Update Service and, in a Debug Build, the Debug Console: no Apps, no IRC, no SD card, and a screen that says so with the address to push an update to. Any normal restart (a `reboot`, an update), or a minute of uptime, resets the count.
-- **Crash reports.** The same boot record keeps which version was running, so after a crash the firmware knows which one crashed, even when a Rollback has switched slots since. ESP-IDF already writes a core dump to its flash partition on a panic; after the restart the firmware prints its summary (task, PC, reason, backtrace) and raises a Notification. The `crash` command shows it again later. In a Debug Build, `scripts/rdbg.py crash` decodes the backtrace and `scripts/rdbg.py coredump` fetches the whole dump for `esp-coredump`, against the ELF of that exact build (`.pio/elves/`, named by version and ELF digest).
+- **Safe Mode.** The firmware counts starts that follow a crash (panic or watchdog) in NVS, first thing at boot. After 3 in a row, it starts only the clock, Wi-Fi, the Update Service and, if it's switched on, the Debug Console: no Apps, no IRC, no SD card, and a screen that says so with the address to push an update to. Any normal restart (a `reboot`, an update), or a minute of uptime, resets the count.
+- **Crash reports.** The same boot record keeps which version was running, so after a crash the firmware knows which one crashed, even when a Rollback has switched slots since. ESP-IDF already writes a core dump to its flash partition on a panic; after the restart the firmware prints its summary (task, PC, reason, backtrace) and raises a Notification. The `crash` command shows it again later. With the Debug Console, `scripts/rdbg.py crash` decodes the backtrace and `scripts/rdbg.py coredump` fetches the whole dump for `esp-coredump`, against the ELF of that exact build (`.pio/elves/`, named by version and ELF digest).
 - **The main loop is watched.** Arduino-ESP32 subscribes only core 0's idle task to the task watchdog, and the main loop runs on core 1: a stuck loop used to hang the device for good, with the screen frozen and the Debug Console unable to run commands. `enableLoopWDT()` makes a loop stuck for 5 s a panic, with a core dump, counted towards Safe Mode. And an installed update no longer depends on the main loop: the Update Service restarts into it by itself after 90 s.
 
 ## Consequences

docs/adr/0006-framework-rebuilt-for-smaller-tls-buffers.md

@@ -0,0 +1,19 @@
+# The framework is rebuilt with our own SDK settings, for smaller TLS buffers
+
+Arduino-ESP32 ships its ESP-IDF libraries prebuilt, with one `sdkconfig` for every ESP32-S3 board. Its TLS settings give every connection a 16 KB receive buffer and a 16 KB send buffer for its whole life. On a device with no PSRAM and about 340 KB of RAM, an IRC connection over TLS left a 12.6 KB low in M2, against a 40 KB floor.
+
+Those settings are compiled into the libraries, so changing them means rebuilding them. pioarduino supports this as a "hybrid compile": `custom_sdkconfig` in `platformio.ini` lists the settings, and the build regenerates the framework's libraries from ESP-IDF (the same 5.5.5 the prebuilt ones come from) before building the app. We set:
+
+- `MBEDTLS_ASYMMETRIC_CONTENT_LEN`, with 16 KB to receive (servers send full TLS records) and **4 KB to send** (IRC lines are short): 12 KB less per connection.
+- `MBEDTLS_DYNAMIC_BUFFER`, `DYNAMIC_FREE_CONFIG_DATA`, `DYNAMIC_FREE_CA_CERT`: buffers allocated when needed, and handshake-only data (the CA chain) freed once connected.
+
+The rebuild also follows the board definition instead of the generic one: PSRAM support is off (the Cardputer ADV has none) and the flash size is 8 MB.
+
+## Consequences
+
+- With IRC connected over TLS, a Debug Build has 78 KB free and a 59 KB low (it was 31 KB and 12.6 KB), and 46 KB at the lowest under the heaviest combined load measured (IRC, two refused installs, a 1.6 MB put and get).
+- The first build after a fresh checkout, or after changing `custom_sdkconfig`, takes about 4 minutes instead of 45 s: it downloads ESP-IDF into the PlatformIO volume and compiles it. Later builds reuse it.
+- Everything the firmware depends on was checked in the regenerated `sdkconfig`: app rollback, core dumps to flash (ELF), the 5 s task watchdog, FreeRTOS run-time stats, the certificate bundle.
+- The project now owns its partition table (`default_8MB.csv`, identical to the framework's), which the hybrid build requires. Changing it would break updates over the air: the app slots must stay where they are.
+- Generated files (`sdkconfig.*`, `managed_components/`, `.dummy/`) are ignored by git.
+- A TLS server that sends records over 16 KB would still fail, as before; one that needs us to send records over 4 KB would now fail. Neither happens with IRC.

docs/adr/0007-own-copy-of-the-sd-driver.md

@@ -0,0 +1,20 @@
+# Our own copy of the SD driver, for one missing byte
+
+Arduino-ESP32's `SD` library talks to the card over SPI through `sd_diskio.cpp`. That driver gives up on a write without saying why, and about once in 1,500 multi-block writes it gave up on one that had worked (issue #21). A 1.7 MB upload failed about three times in ten; before M3, the retry on top of it then filled the gap with zeros.
+
+The cause, measured with a driver that records where it stops: after the "Stop Tran" token that ends a multi-block write, a card takes about a byte of clock to signal busy. The driver deselects, selects again, and reads one byte to see whether the card is ready. Read too early, that byte is 0xFF, "ready"; the status check (CMD13) then goes out while the card is still programming, and its answer (0xFF, 0x1F) is taken for an error. Every failure seen was this one: all blocks accepted, then a status that isn't one. ChaN's reference driver, which FatFs ships as its example, sends a dummy byte after selecting the card for this reason. Arduino's doesn't.
+
+PlatformIO links the framework's library objects directly, so one file can't be replaced from `src`. A project library with the same name takes its place: **`lib/SD` is Arduino-ESP32 3.3.12's SD library (Apache-2.0), with `sd_diskio.cpp` changed** and the other files as they came. The changes are marked `roro:`:
+
+- A dummy byte after selecting the card, before the ready test, and one after Stop Tran.
+- Each place a write gives up records the step and the card's answer (`sd_fault.h`): `info` shows the count, and the Debug Console's `put` prints the detail.
+
+Halving the SPI clock to 10 MHz didn't change the failure rate, so the card stays at 20 MHz.
+
+## Consequences
+
+- 30 uploads of 1.7 MB in a row, each read back and compared by SHA-256, ten of them with the LoRa radio listening on the same bus: no write fault. Before: 3 failures in 10.
+- Every writer gains: Logs, Tracks, Gemini pages, Saved Pages, Captures and Update Files installed from the card all go through this driver, and none of them checked.
+- **The copy has to follow the framework.** When the platform is updated, compare `lib/SD` with the new `libraries/SD` and carry the `roro:` changes over. If upstream fixes the ready test, drop the copy. Reported as [arduino-esp32#12970](https://github.com/espressif/arduino-esp32/issues/12970); issue #39 follows it.
+- One more defect was read in the code and left alone, because nothing here exercises it: the driver tests the card's answer to a data block against 0x0A and 0x0C, values it can't take (accepted is 0x05, CRC error 0x0B, write error 0x0D), so a block rejected for a CRC error is never resent. No such rejection was seen in any failure. If `DataToken` faults ever show in `info`, that's the next fix.
+- A fault is now counted and explained instead of silent, so the next cause, if there is one, starts with evidence.

docs/adr/0008-ci-signs-releases.md

@@ -0,0 +1,17 @@
+# CI signs releases with the project's key
+
+A tag `v*` is built, signed and published by Gitea Actions with nobody at a keyboard. The signing key of ADR 0003 is therefore held twice: in `~/.config/roro9stack/ota-key.pem` on the development machine, as before, and as the repository secret `OTA_SIGNING_KEY`, which the release step writes to a file for as long as it runs.
+
+We chose this over signing by hand after CI has built (a command per release, the key in one place), and over a second key for CI that the firmware would also trust. A release that needs a manual step isn't made on the day it's ready, and issue #6, the device installing releases by itself, needs releases that are always there and always signed.
+
+## What it costs
+
+- **Whoever can run a workflow in this repository can sign firmware every device accepts.** That means: anyone who can push to it, the runner's host and whoever administers it, and the Gitea instance with its database, where the secret is stored. Before, it took the development machine.
+- The runner executes jobs **on its own host**, not in a container, as a user who can use Docker. A workflow is not confined.
+- Pull requests from forks must never run with this secret. Gitea doesn't pass secrets to them; the workflow also only runs on pushes and by hand.
+
+## What limits it
+
+- The release step checks the signed file against the public key in the sources it built (`scripts/ota_verify.py`): a wrong or replaced secret stops the release instead of publishing a file no device takes.
+- ADR 0003's way out stays: a firmware release can carry a new public key. If the secret is ever in doubt, make a new pair, ship it in a release signed with the old key, and replace the secret.
+- A device still only installs what it's told to (until #6), keeps a new image on Probation, and rolls back one that doesn't hold.

docs/adr/0009-the-device-trusts-the-isrg-roots.md

@@ -0,0 +1,22 @@
+# The device trusts the two ISRG roots for what it fetches
+
+The firmware talks to the project's Gitea over HTTPS (issue #6, and #4 after it). A TLS client has to decide whose certificates it believes. Three ways were possible:
+
+- **The framework's bundle**, about 130 certificate authorities (about 60 KB of flash). Any of them could vouch for `git.twis.la`.
+- **Pin the server's certificate**, as the Gemini App does for capsules. The server's certificate is replaced every few months, so a pin would ask the question again at every renewal.
+- **Carry the roots the server's chain ends in:** `ISRG Root X1` (RSA 4096) and `ISRG Root X2` (ECDSA P-384), the Let's Encrypt roots, about 2.7 KB of flash (`src/platform/ca_roots.h`).
+
+We chose the third. The chain and the name are checked by mbedTLS during the handshake. It trusts one organisation's two roots, valid until 2035 and 2040, and a renewal changes nothing.
+
+## What it costs
+
+- **If the server moves to another CA, the device can no longer reach it**, and the next firmware, carrying that CA's root, has to come from the PC or the SD card. Both still work; they don't use TLS.
+- The roots are public data checked against the published fingerprints (listed in the file), refreshed by hand if Let's Encrypt ever changes them.
+
+## What it doesn't change
+
+The Update File's own signature (ADR 0003) is what decides what gets installed. A hijacked connection could hide a release, or serve an older signed one, but never make the device install firmware that isn't ours. The TLS check matters more for #4, where a token will travel over it.
+
+## Measured while building it
+
+A TLS connection to this server peaks at about 52 KB of heap, **the same whether the certificate is checked or not**, so skipping the check would have saved nothing. The cost is the connection itself (record buffers and handshake), not the trust decision.

docs/adr/0010-debug-console-in-every-build.md

@@ -0,0 +1,30 @@
+# The Debug Console is in every build, off until its owner switches it on
+
+There is **one firmware**. The Debug Console of ADR 0004 is compiled into it, and so are the commands that used to exist only in Debug Builds. It listens only while **Settings → Debug Console** is on, which is not the default, and it lets in whoever proves they hold **the device's own token**. The `cardputer-adv-debug` environment, `RORO_DEBUG`, the `+debug` version and the token compiled in from the builder's machine are gone.
+
+ADR 0004 kept the console out of release builds with one argument: a console that runs commands is a remote control, so in a release nothing should listen. That argument was never whole: the Update Service has listened on TCP 3232 in every build since Firmware Updates exist, guarded by a signature. A listener that is off by default and guarded by a secret the device made itself is the same kind of trade, and what the split cost had grown:
+
+- **What was tested wasn't what shipped.** Development ran on Debug Builds; releases were a different binary, built to be published and never run by the person who wrote them.
+- **Debug Builds couldn't be published**, since each carried its builder's token. So the console, `rdbg.py`, screenshots and crash decoding were for whoever built the firmware, and nobody else.
+- **Rules that existed only to protect the console:** a Debug Build never installed a release (it would have lost the console), `update install … force` to do it anyway, "keep a Debug Build in the fallback slot", versions with `+debug` that had to compare equal to their release.
+- **CI built two firmwares** on every pull request and every tag.
+
+## How it works
+
+- **Off means nothing is there.** With the setting off, no socket listens, the console's task doesn't exist and neither does its 4 KB ring: a device that never uses the console pays for it in flash (30 KB more than the release build was) and 88 bytes of static RAM, measured. A missing or invalid stored setting counts as off.
+- **The token is the device's.** The first time the console is switched on, the device makes one from its hardware random generator: 100 bits, as 20 characters of Crockford's base32 (`K7QF-3M2X-9WBD-HT4P-6RNC`), shown on the Debug Console page and nowhere else. It can be replaced by one typed by hand, of 16 to 64 characters. It is stored with the other settings and is never printed on a console.
+- **The token never crosses the network.** The device sends 16 random bytes; the client answers with their HMAC-SHA256 keyed by the token. Someone on the same Wi-Fi who records a login has nothing they can use for the next one.
+- **Five wrong answers in a row** close the console to everyone for a minute, with a Notification naming the address they came from. A wrong answer still costs a second.
+- **`DBG` in the Status Bar** while the console listens, bright while a client is connected.
+- **USB serial can set it up:** `debug on`, `debug token <value>`, `debug token new`. `scripts/flash.sh --debug` uses them to give a freshly flashed device the developer's token. Whoever holds the cable can flash anything anyway (ADR 0003); the console itself can only switch itself off.
+- **Safe Mode** starts the console if it's switched on: the settings are read before Safe Mode is decided.
+
+## Consequences
+
+- **"Nothing listens" now rests on one stored setting**, not on absent code. That setting is typed, validated and host-tested, and its default is off; a bug that flipped it would have to come from code that already runs on the device.
+- **Whoever has the token and the network has the device:** the console, its keys, the SD card's files, a restart. Not its firmware: an update still has to be signed (ADR 0003).
+- **The stream is still plain text.** The token is safe from an eavesdropper; what the console prints, and the files it carries, are not. TLS would cost about 52 KB of the 107 KB there is, next to IRC's own connection: not for a console.
+- **An old `rdbg.py` can't talk to a new firmware**, and the reverse: the first line of the protocol changed. Accepted, with one user.
+- **A device whose settings are damaged has no console in Safe Mode**, only the signed update push. Before, a Debug Build always had it.
+- **The commands that crash, damage a download or fill a folder on purpose** are in every build. They need the cable or the token, like everything else.
+- **Releases already publish their ELF**, so `rdbg.py crash` fetches it when it isn't in `.pio/elves/`: crash reports can be decoded without having built the firmware.

docs/milestones/F1.md

@@ -0,0 +1,161 @@
+# F1 — Files and Notes
+
+**Status:** in progress. The Storage App (issue #3) shipped as **v0.9.0** on 2026-10-06. Notes (#19) shipped as **v0.10.0** the same day. The card as a USB drive (#1) comes after.
+
+**Goal:** get at what's on the SD card from the device itself: browse it, look inside the files the firmware writes, copy, move, rename and delete, and keep notes. A side milestone, like G1 and S1; Files and Notes were M3's original second half (Q30, Q89).
+
+## The Storage App (issue #3)
+
+Until now the card could be looked at only through the Debug Console (`ls`, `get`, `put`), and Settings > Storage could only delete whole categories by age.
+
+**On the card today:** six top-level folders, `irc`, `wifi`, `updates`, `gnss`, `gemini` and `captures`. No `notes` yet; settings are in flash, not on the card.
+
+### Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q128 | An App of its own, **Storage**, in the Launcher. **Settings > Storage goes away:** its usage figures, Storage Clean-up and "Erase SD card" move into the App, under **Maintenance**, behind a warning that these delete things for good. |
+| Q129 | A row shows the name, then the size or "folder", then the date modified. Folders first, then by name; `s` cycles the sort (name, date, size). The top line shows the path and the card's free space. |
+| Q130 | Nothing is hidden. **Read-only:** `/gemini/cache`; any file the firmware has open right now (today's IRC log, a Track or Capture being recorded, a file being received); and the top-level folders themselves, which can't be renamed or deleted though their contents can. **Everything else, the user's own data included, can be renamed, moved or deleted**, always after a confirmation. |
+| Q131 | One item at a time, with a clipboard: Enter opens; Back goes up, and leaves the App at the top; `c` copy, `x` cut, `v` paste into the current folder; `r` rename; `d` delete; `n` new folder; `i` details. |
+| Q132 | Copy, move and delete work on folders too, recursively. The confirmation says what's inside: "Delete *saved* and its 42 files?". |
+| Q133 | A copy is a job on the storage task in 4 KB pieces, with a progress Toast; Back cancels it. It checks free space first and asks before replacing anything. **Afterwards the sizes are compared**, not the contents: the driver is trusted since v0.6.1 (ADR 0007). A move within the card is a rename. |
+| Q134 | Viewers by type. **Text** (`.txt`, `.log`, `.gmi`, `.csv`, `.gpx`, and anything that looks like text): read from the card as you scroll, so size doesn't matter; logs open at the end. **`.pcap`:** the LoRa Scanner's packet list. **`.gpx`:** a summary (start, duration, points, distance), Tab for the text. **`.ota`:** version, size, whether the signature is valid; Enter installs through Update from SD. **Anything else:** a hex dump. |
+| Q135 | No editing: that comes with Notes (#19). |
+| Q136 | A listing holds **up to 256 entries**, packed, about 10 KB; a bigger folder shows the first 256 by name and says how many more there are. The App refuses to open below the memory floors (Q86). |
+| Q137 | **The Clock also sets the system time**, so files are dated correctly with GNSS alone and not only after NTP. A file dated before 2020 shows "-". |
+| Q138 | Console: `cp`, `mv` and `mkdir`, next to `ls` and `rm`. |
+| Q139 | Left out, each with its issue: selecting several items (#41), finding files by name (#42), opening a `.gmi` in the Gemini App (#43), a table view for `.csv` (#44), images (#45). |
+| Q140 | Ships as **v0.9.0** when done and checked. |
+
+### Done when
+
+- The Storage App lists any folder of the card with sizes and dates, sorted three ways, and says so when a folder has more than 256 entries.
+- A file can be copied, moved, renamed and deleted, and a folder too; a new folder can be made. Each destructive action asks first; a copy shows progress and can be cancelled.
+- The read-only rules of Q130 hold, with a reason given when something is refused.
+- Each viewer of Q134 opens its type, and a 1 MB text file scrolls without loading whole.
+- Maintenance shows the card's usage and does what Settings > Storage did, behind its warning; Settings no longer has a Storage row; the Storage Warning points at the Storage App.
+- A file written with only a GNSS Fix (no Wi-Fi) is dated correctly.
+- Free heap stays above the floors with the App open, Wi-Fi and IRC on TLS.
+
+### Work breakdown
+
+1. **Model** (host-tested): paths and names, the read-only rules, the packed listing and its sorts, file types, sizes and dates for display, the GPX summary.
+2. **Card operations:** listing a folder, copy, move, delete (recursive, counted), new folder, as storage jobs with progress and cancel; `cp`, `mv`, `mkdir`; the Clock sets the system time.
+3. **The App:** browsing, the clipboard, dialogs, details.
+4. **Maintenance:** usage, Clean-up and Erase moved in from Settings, with the warning.
+5. **Viewers:** text, hex, `.pcap`, `.gpx`, `.ota`.
+6. **Checks on the device**, recorded here.
+
+### As built
+
+- **`FileOps`** (`src/services/file_ops`) does the card's work for the App and for the console alike: list, count, copy, move, delete, new folder. One operation at a time on the storage task, **in turns of about 150 ms** that queue themselves again, so Log lines and a Capture are written in between. The rules of Q130 are checked there, whoever asks.
+- **A listing reads the folder straight from FatFs.** Through the Arduino `File`, every entry was looked up by name again for its size and again for its date: 329 entries took over two seconds. One pass now, and it's there before the screen has redrawn. Counting, copying and deleting still walk with `File`; they show progress and can be stopped.
+- **A copy shows its progress in a box in the App**, not a Toast (Q133): it has a bar and says Back cancels. A cancelled or failed copy deletes what it had written. The copy gets today's date, like `cp`.
+- **The viewers** (`src/apps/file_viewer`, models in `lib/files`): text through `TextPager`, which reads about a kilobyte around the screen and wraps at spaces, 38 columns; going back a line wraps the paragraph before again, so a file reads the same in both directions. A `.pcap`, a `.gpx` and an `.ota` are read through once by a storage job, in the same 150 ms turns. An Update File is fed to the installer's own parser with a sink that writes nothing, so "would it install" is the same answer an install gives.
+- **Tab** in a viewer shows the same file as hex, or as text (not in Q134).
+- **Maintenance** is the last row at the top of the card, and `m` anywhere in the App. It's the old Settings > Storage page behind a dialog.
+- **The Storage Warning** was only ever a Toast; "selecting it opens Storage Clean-up" (CONTEXT.md) was never built. It now reads "SD card over 80% full: see Storage".
+- **Console:** `cp`, `mv`, `mkdir` (Q138), and `rm` and `du` through the same code, so `rm` now takes folders and follows the rules; `ls` shows dates. Debug Builds: `sd fill <folder> <count>` makes test files.
+
+### Checks on the device (2026-10-06, v0.8.1-2 Debug Build)
+
+All in a scratch folder, `/f1test`, removed afterwards.
+
+| Check | Result |
+|---|---|
+| Host tests | 424 pass (411 before the viewers' models) |
+| Browsing | Folders first, sizes and dates, the three sorts; a 300-file and a 329-file folder show "first 256 of 300" and "of 329" |
+| New folder, rename, copy, cut and paste, delete | Each works on a file and on a folder; a copy next to its original is named `(2)`; a name in the way asks "Replace it?" |
+| A folder of 11 files, 8.4 MB, copied | 19.4 s, 435 KB/s, the bar moving; two Log lines queued meanwhile were written |
+| The same copy cancelled at 1.8 MB | "Cancelled: nothing was copied", and nothing was left behind |
+| Delete | 341 files in 9.7 s; the dialog had counted them first |
+| Read-only rules | `/irc`, `/gnss` (top-level folders), `/`, `/gemini/cache` and a folder made inside it, a folder into itself, a name with `:`; a Capture being recorded and the folder holding it; a folder under `/irc` while IRC runs. Each refused with its reason; the Capture could still be copied |
+| Text | A 1 MB log opens at its last line at once; top, pages, lines; a file without an extension that looks like text opens as text |
+| Hex | A 5 KB binary file; Tab from any other viewer |
+| `.pcap` | A LoRa Capture: 3 packets as the Scanner lists them, Enter shows the Meshtastic header and bytes |
+| `.gpx` | 400 points: start, 33 min 15 s, 4.68 km; Tab shows the text |
+| `.ota` | A signed file: version, "intact", "older than what's running", Enter asks to install (not confirmed). A tampered one: "image corrupted (hash mismatch)" |
+| Maintenance | The warning, then usage, Clean-up's categories and Erase (not run) |
+| Date with GNSS only | NTP pointed at an address that doesn't answer, restart: the Clock came from the Fix, and a folder made then is dated 2026-10-06 08:39. A Track from the day before, written the same way by v0.8.1, shows "-" |
+| Memory | IRC connected, the App open on 256 entries: 61 KB free (70 KB before opening). Lowest since boot 29.7 KB, during IRC's TLS handshake |
+| Stacks | `storage` 3.1 KB free of 6 KB at worst, `loopTask` 1.5 KB |
+
+**Not checked by hand:** how the keys feel on the device itself; everything above was driven through the Debug Console's `key` command and screenshots.
+
+**One slip during the checks:** a scripted key sequence ran in the wrong folder and renamed `/gemini/saved` to `saved2`, then copied it to the top of the card. Both were put right at once (renamed back, the copy deleted; 7 files, 53,798 bytes, as before).
+
+**Found on the way:** a panic at Wi-Fi join, there since v0.7.0 (SNTP started twice, issue #46). Fixed in v0.9.0.
+
+## Notes (issue #19)
+
+Plain text notes on the SD card, written on the device. Q30 settled the base: `.txt` files in `/notes`, created, edited and deleted from the device, never offered by Storage Clean-up.
+
+### Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q141 | A **Notes** App in the Launcher. One row per note: its first line as the title, then the date. Newest first; `s` switches to by name. `n` new, Enter opens, `d` deletes after a confirmation, `r` renames the file. |
+| Q142 | A new note's file name is never typed: it comes from the first line when the note is first saved (`shopping-list.txt`), or `note-20261006-0919.txt` if that line is empty. It doesn't change afterwards unless the note is renamed. |
+| Q143 | **Autosave, no "discard changes?" prompt:** five seconds after the last key, on leaving the note or the App, and when the screen turns off. A save writes a temporary file and renames it over the note, so a power cut loses the last few seconds at most. A temporary file left behind is offered back at the next open. |
+| Q144 | The whole note is in memory while it's edited, up to **16 KB**. A bigger text file opens read-only in the Storage App's viewer. The App refuses to open below the memory floors (Q86). **Editing files of any size must come in a later release: issue #47.** |
+| Q145 | The editor wraps at spaces, 38 columns by 8 rows, with a line for the name and the state. Enter is a new line, Del deletes backwards, Fn+arrows move (the Text Entry rule), Ctrl+A and Ctrl+E go to the start and the end of the line, Tab types two spaces, Back saves and returns. The Compose Key works as elsewhere. |
+| Q146 | The Storage App's text viewer gets `e`: edit this file with the same editor, for a text file up to 16 KB that isn't read-only. That lifts Q135 without Apps opening each other (#43 stays). |
+| Q147 | The list is flat: the files directly in `/notes`. Sub-folders are reached through the Storage App. |
+| Q148 | UTF-8, LF line ends; a file with CRLF is saved back with LF. Characters the font lacks are kept on save. |
+| Q149 | Left out, each with its issue: editing files of any size (#47), searching inside notes (#48), undo (#49), selecting and copying text (#50). |
+| Q150 | Ships as **v0.10.0** when built and checked on the device. |
+
+### Done when
+
+- A note can be started, typed with accents, left and found again in the list under its first line; renamed; deleted after a confirmation.
+- What's typed is on the card five seconds after the last key, and after Back, Home, or the screen turning off, without a prompt.
+- Pulling the power while typing loses a few seconds at most, and the note is never left empty or half-written.
+- The cursor moves by character and by line through wrapped text, and the screen follows it; a 16 KB note edits without lag.
+- A note at 16 KB refuses more text and says so; a bigger file opens read-only.
+- `e` in the Storage App's text viewer edits a file; a read-only one is refused with its reason.
+- Free heap stays above the floors with a 16 KB note open and IRC connected.
+
+### Work breakdown
+
+1. **Model** (host-tested): the text buffer with its cursor, wrapping and scrolling; file names from first lines.
+2. **The editor on the device:** loading, drawing, keys, autosave through a temporary file, recovery.
+3. **The Notes App:** the list with titles, new, rename, delete.
+4. **`e` in the Storage App.**
+5. **Checks on the device**, recorded here.
+
+### As built
+
+- **`NoteText`** (`lib/notes`, host-tested) is the text, its cursor and the screen around it. A line owns the space or the newline it ends with, so every byte is on exactly one line and the cursor has one place for each. **No index of lines is kept:** a note of newlines alone would need twice its own size for one. Where a line starts is worked out from the start of its paragraph.
+- **One buffer, 16 KB, for as long as the editor is open.** It's reserved when the note is opened, the file is read straight into it, and typing never makes it grow. On this device a failed allocation is an abort, and with IRC connected the largest free block is about 31 KB whatever the total says: the first version read the file into one string and copied it into another, and opening a full note with IRC connected restarted the device. The editor now also refuses to open without a free block of 24 KB.
+- **`NoteEditor`** (`src/apps/note_editor`) is shared by the Notes App and the Storage App's `e`. A save runs on the storage task while the main loop waits for it: no second copy of the note, and at 16 KB the wait is a fraction of a second at a moment when nobody has typed for five.
+- **A save** writes `<note>.tmp`, checks its size, deletes the note and renames the temporary file (FAT can't rename onto a file). A cut between the last two steps leaves only the `.tmp`: the Notes list puts such a file back under its name. A `.tmp` next to its note is an unfinished save: opening the note offers it.
+- **Titles** in the list are read from the card for the eight rows on screen, when the list moves.
+- **Before powering off**, the firmware now leaves the foreground App (`PowerService::beforePowerOff`), which makes the editor save.
+- Shift or Alt with Fn+Up and Fn+Down moves a page (not in Q145).
+
+### Found on the way
+
+- **The screen could go "off" for one tick after a key sent through the Debug Console**, and the next key was then swallowed as a wake-up: the `key` command stamps the power timer from `millis()`, the power tick compares with its pass's older time, and the unsigned difference read as 49 days idle. The same shape as #46. Fixed in `PowerPolicy::update` with a test. Keys from the keyboard were never affected. It explains remote keys "lost" in earlier sessions.
+- **`scripts/rdbg.py` held back piped lines** written while it was still connecting, until the next line came (a buffered `readline()` behind `select()`). Fixed.
+
+### Checks on the device (2026-10-06, Debug Build of branch `notes`)
+
+Test notes were made in `/notes` and removed afterwards; the folder is left, empty.
+
+| Check | Result |
+|---|---|
+| Host tests | 439 pass |
+| A first note | "No notes yet", `n`, typed three lines: the top line says "typing", then "saved" five seconds after the last key, under `shopping-list.txt`. 63 keys in a row all arrived |
+| Leaving | Back saves and returns to the list, which shows the note under its first line. Home in the middle of a new note saved it as `ideas.txt` |
+| The cursor | Down, Right, an insertion in the middle of a line; the screen scrolls through a note of about 230 lines |
+| A power cut | Typed, waited seven seconds, typed more and restarted the device at once (`reset`): the note has what was saved, whole, and not the last keys |
+| An unfinished save | A `.tmp` next to its note: "Unsaved copy... Keep the note / Use the copy"; using it brings its text back and saves it. A `.tmp` alone was put back under its name when the list opened |
+| 16 KB | A note of exactly 16,384 bytes opens and scrolls; one more character: "This note is full: 16 KB". A file of 16,398 bytes: "Too big to edit: 16 KB at most" |
+| Rename, delete, sort | `r` renamed `orphan.txt` to `orphan2.txt`; `d` asked, then deleted; `s` switched between newest first and by file name |
+| `e` in the Storage App | A note opened from the text viewer, edited, saved on Back; the listing shows its new size |
+| Memory | IRC connected, the full 16 KB note open: 55 KB free, largest block 31.7 KB (72 KB free before opening) |
+
+**Not checked:** accents through the Compose Key and Ctrl+A / Ctrl+E (the remote `key` command can't send them; the model's tests cover both), the power button's save (it needs a hand on the device), a missing card, and how typing feels on the keyboard itself.
+
+**One slip during the checks:** a key sequence sent right after a restart opened IRC instead of Notes, and the test letters went into IRC's input line. Nothing was sent: the line was cleared and the App left. IRC connected to Libera as it does when opened.

docs/milestones/G1.md

@@ -0,0 +1,61 @@
+# G1 — Gemini client
+
+**Status:** done, tagged v0.5.0. Every step was checked on the device; reading Saved Pages with Wi-Fi off was checked by hand (2026-10-05).
+
+**Goal:** browse Geminispace from the Cardputer: fetch and read gemtext over TLS, follow links, answer input prompts, keep bookmarks, and save pages to the SD card to read later, offline. A side milestone between M2 and M3, tagged v0.5.0 when done.
+
+Gemini (geminiprotocol.net): one request per TLS connection on port 1965, the request is the URL and CRLF, the response a `<status> <meta>` header line, then the body. Most capsules use self-signed certificates: trust on first use is the norm.
+
+## Decisions (design round 2026-10-05)
+
+| # | Decision |
+|---|---|
+| Q70 | A milestone of its own, **G1**, before M3: plan, tests first, measured on the device, tagged v0.5.0. |
+| Q71 | **TOFU:** the first certificate seen for a host is pinned (SHA-256, in NVS). If it changes, the page isn't shown; a dialog shows both fingerprints and asks whether to trust the new one. Self-signed or expired certificates are fine; only a change counts. |
+| Q72 | Responses: 1x input (11 hidden, for passwords), 2x content, up to 5 redirects (3x), 4x/5x errors with the server's message. 6x (client certificates): "not supported". |
+| Q73 | `text/gemini` is rendered, other `text/*` shown as plain text. Anything else can be saved to `/gemini/downloads/`, not shown. |
+| Q74 | Up to **64 KB on screen**, larger pages truncated with a notice. Saving streams to the card, so a larger page is saved whole. |
+| Q75 | Gemtext rendering: text wrapped to the 40-column screen; `#`/`##`/`###` headings in bold and accent; `*` lists with bullets; `>` quotes indented and muted; preformatted blocks unwrapped, Left/Right to scroll; `=>` links with their label, numbered. |
+| Q76 | Up/Down scroll; Tab and Shift+Tab move between links; Enter follows; Backspace goes back; `g` opens the address line. Links to other protocols show their URL and aren't followed. |
+| Q77 | Back history of 20 URLs in RAM, with scroll positions; going back refetches (or reopens a Saved Page). **Bookmarks** in `/gemini/bookmarks.gmi` (a gemtext page, shown on the start page); `b` adds the current page. Without a card, a built-in start page. |
+| Q78 | Start page: bookmarks, then Saved Pages, then defaults: geminiprotocol.net, a search engine (kennedy.gemi.dev), an aggregator (Cosmos; Antenna was down when measured). |
+| Q79 | UTF-8 decoded; characters outside the Latin-1 fonts shown as `?`. |
+| Q80 | IRC and Gemini can run together: each fetch opens one connection, reads and closes it. If there isn't memory for a second TLS connection, the fetch fails with a clear message and IRC is untouched. Measured in step 1. |
+| Q81 | Debug aid: `gemini get <url>` prints the status, MIME type, size, certificate fingerprint and the first lines. URL resolution (RFC 3986), the response header and gemtext parsing are host-tested. |
+| Q82 | `s` saves the page on screen as a **Saved Page**: `/gemini/saved/<host>/<path>.gmi`, the gemtext as received plus a first line with its URL and save date. Saving again replaces it, and says so. |
+| Q83 | `S` saves the page and the pages it links to, one level deep: gemtext only, same host only, at most 30 pages, in the background with a progress Toast. |
+| Q84 | The start page lists Saved Pages, newest first, grouped by capsule; they open with no network. In a Saved Page, a link to another Saved Page opens the saved copy; other links fetch online if Wi-Fi is up, or say "not saved, offline". A Saved Page shows when it was saved; `r` refreshes it. |
+| Q86 | *Decided after step 1, revised after Q88.* **Two floors:** free heap stays above 40 KB in steady state; a fetch refuses to start below **55 KB** free ("not enough memory: stop IRC or retry"). The firmware's own allocations during a fetch (a page in RAM, a window) keep 20 KB free. With IRC connected, the TLS connection itself can briefly take the heap lower, depending on the server's record sizes: measured 24, 19.5, 15.5 and **13 KB**. *Accepted:* about 12 KB for a moment during a fetch with IRC up, rather than refusing most fetches (a 70 KB start floor) or dropping IRC's connection for each page. |
+| Q87 | *Decided in step 3.* **With a card, every page streams to `/gemini/cache/page.gmi`** in 1 KB pieces while its TLS connection is open; once the connection closes and its ~45 KB is back, the page is loaded into RAM as far as the 40 KB floor allows. The whole page stays on the card (Saved Pages copy it). Without a card, the page goes straight to RAM under the same two floors. Pages are held as lines in 4 KB chunks, never one large block (the largest free block with IRC connected is about 31 KB). |
+| Q88 | *Added after step 6.* **A page bigger than memory allows is read from the card as you scroll.** Opening it, one pass over its file counts the lines, records where every 64th starts (and whether it's inside a preformatted block), and loads the first window. Scrolling near either end of the window reads the next or previous one in the background, keeping the line on top of the screen where it is; the scrollbar follows the whole page. Display pages alternate between two cache files, so the one on screen is never overwritten by the next fetch; background jobs use a third. |
+| Q85 | Saved Pages are deleted from the App only (`d`, with confirmation), never by Storage Clean-up's age rules, like Notes. |
+
+## Measured (step 1)
+
+- `gemini://geminiprotocol.net/`: `20 text/gemini`, 1,184 bytes, TLS handshake 0.7–1.1 s, whole fetch 0.7–1.1 s; kennedy.gemi.dev 1.9 s. The fetch task's stack peaks at about 3.6 KB of 6.
+- **Heap, Debug Build, IRC connected over TLS:** about 68 KB free before a fetch. After the handshake the fetch holds about 32 KB (36–40 KB left); the handshake itself (certificate chain parsed with the 16 KB receive buffer allocated) dips to about **24 KB** for a second or two. Nothing leaks: the heap after matches the heap before.
+- **Step 3, Cosmos (31.6 KB) with IRC connected:** first stopped at 4.6 KB (RAM only, the transfer's 20 KB floor). Streamed to the card: the whole page on the card, 20 KB of it loaded, lowest free heap 19.5 KB during the transfer and 43 KB once loaded. Without IRC: the whole page in RAM. Redirects (Cosmos `31`), input (`10`), not found (`51`) and a changed certificate (refused, both fingerprints shown) all checked on the device.
+- **Steps 4–6 on the device:** Project Gemini and its relative links, Back with the scroll restored, a refused YouTube link; `b` bookmarks, `s` saves (and says when it replaced an older copy), `S` saved 6 of 6 pages, the start page lists both; a Saved Page opens from the card with its origin, its saved links open saved copies, `r` refreshes, `d` asks first; Kennedy's input prompt sent "cardputer" and got 87 results; emoji drawn as `?`.
+- **A bug found there:** refreshing first loaded the whole Saved Page into RAM just to read its origin, next to the App's copy and a TLS connection: the heap fell to 436 bytes. Now only the first line is read, and every fetch (pages, saves, refreshes) checks the 55 KB start floor. Lowest since boot afterwards: 53.8 KB.
+- **Windowed pages (Q88), Cosmos with IRC connected:** 226 of 419 lines in memory at first; paging down loaded lines 192–419 in one window, scrolling back up loaded 64 onwards, then 0 onwards. Window budgets count the memory the old window gives back.
+- **Heap during a fetch with IRC connected:** lowest 13–15.5 KB in later runs (24 and 19.5 KB earlier), the TLS receive buffers varying with the server's records. Accepted (Q86, revised).
+- Antenna (`warmedal.se`) doesn't answer, from the PC either; the default aggregator becomes Cosmos (`gemini://skyjake.fi/~Cosmos/`, which redirects to `cosmos.skyjake.fi`).
+
+## Done when
+
+- `gemini get gemini://geminiprotocol.net/` prints the header, size and fingerprint on the console.
+- The Gemini App opens the start page, follows links (relative ones included), goes back, and follows redirects.
+- An input prompt (e.g. a search) takes a query and shows the results.
+- A changed certificate stops the page and asks.
+- `s` saves a page, `S` a page and its links; with Wi-Fi off, Saved Pages open and their saved links work.
+- Bookmarks are added with `b` and listed on the start page.
+- With IRC connected over TLS, a fetch still works, and the free heap stays above 40 KB.
+
+## Work breakdown
+
+1. **Two TLS connections:** measure the heap with IRC connected while a Gemini fetch runs.
+2. **Parsers** (host-tested): URL parsing and relative resolution, the response header, gemtext lines.
+3. **Fetch** on its own task, with TOFU and `gemini get`.
+4. **Gemini App:** rendering, scrolling, links, history, the address line.
+5. **Input prompts, redirects, bookmarks, downloads.**
+6. **Saved Pages,** then saving with linked pages.

docs/milestones/M2.md

@@ -0,0 +1,59 @@
+# M2 — GNSS
+
+**Status:** done on the device (branch `m2`): every "Done when" item below is met.
+
+## Measured
+
+- **Cold start** (`$PCAS10,2`) to a 3D Fix, by a window: **73 s**, 5 satellites used of 8 in view. A restart of the ESP32 alone keeps the receiver's Fix (the Cap stays powered).
+- By a window: 3D Fix from GPS, GLONASS, Galileo and BeiDou, up to 14 of 17 satellites used, HDOP 1.0–1.3.
+- **Heap, Debug Build, GNSS on, IRC on TLS** (floor 40 KB; v0.2.1 had a 79 KB low):
+
+  | | Free | Lowest |
+  |---|---|---|
+  | Start of M2 | 31 KB | 12.6 KB |
+  | Stacks and buffers trimmed by measurement | 46 KB | 18 KB |
+  | mDNS removed | 54 KB | 34 KB |
+  | Framework rebuilt with smaller TLS buffers (ADR 0006) | **78 KB** | **59 KB** |
+
+  Under the heaviest combined load measured (IRC, two refused installs, a 1.6 MB put and get), the low is 46 KB. The cost had come mostly from the OTA and Debug Build work, not GNSS. Stacks were set to measured peak plus about 2 KB (loop 6 KB, update 5, storage 6, irc 6); after a TLS handshake the irc task has 1.7 KB left. IRC can now be stopped by hand (`/quit` in any state, `irc stop`), which frees its TLS memory.
+
+**Goal:** the device knows where it is and what time it is without a network: a GNSS Service in the background, a GNSS App with the position and a sky view of the satellites, the clock set from satellites when there's no NTP, and Tracks recorded to the SD card.
+
+**Hardware:** the Cap LoRa-1262 carries an ATGM336H-6N (AT6668), multi-constellation (GPS, BeiDou, Galileo, GLONASS, QZSS), with a ceramic antenna. NMEA over UART, 115200 8N1. **Measured (step 1, `gnss probe`): RX GPIO 15, TX GPIO 13, 115200 8N1**, as in Meshtastic's board file; M5Stack's page names GPIO 8 and 9, which are the internal I2C bus the keyboard controller sits on. Output is NMEA 4.10 style: `GN` RMC, VTG and GGA, one GSA per constellation with the system ID (1 GPS, 2 GLONASS, 3 Galileo, 4 BeiDou, 5 QZSS) in its last field, and a GSV sequence per constellation and signal (`GP`, `GL`, `GA`, …) with the signal ID last. RMC carries a time even without a Fix (status `V`), so only a Fix makes it trustworthy.
+
+## Decisions (design round 2026-10-04)
+
+| # | Decision |
+|---|---|
+| Q58 | Settings has a GNSS On/Off switch, **On by default**. Off puts the receiver in standby. *Measured:* `$PCAS12,<seconds>` (CASIC) stops its output within a second, for up to at least 65535 s, and any command wakes it within a second; Off sends `PCAS12,65535` (renewed hourly), On sends a hot start, `PCAS10,0`. |
+| Q59 | The **GNSS App** has two views, switched with Tab. *Position*: latitude, longitude, altitude, speed, course, Fix (none / 2D / 3D), satellites used and in view, HDOP, UTC time. *Sky*: the satellites placed by azimuth and elevation, coloured by constellation, filled when used in the Fix. |
+| Q60 | "Radar" in M2 means the Sky view. A radar of other Nodes by distance and bearing needs the mesh: M4. |
+| Q61 | The **Status Bar** shows a GNSS mark: absent when off, muted while searching, normal with a 2D Fix, with the satellite count with a 3D Fix. |
+| Q62 | GNSS time **sets the clock once there's a Fix**, and refreshes it every 10 minutes. *Revised in step 3:* the clock's trust order from M0 (Mesh < NTP < GNSS) already ranks GNSS above NTP, which is right: GNSS time is at least as accurate. So GNSS also corrects a clock NTP set, not only an unset one. |
+| Q63 | A **Track** is started and stopped in the GNSS App. It's written as GPX to `/gnss/tracks/<YYYYMMDD-HHMMSS>.gpx`, a point every 5 s when the position moved more than 5 m. It keeps recording with the App closed, with a Toast on start and stop and a Status Bar mark, and gets its own Storage Clean-up category. |
+| Q64 | Coordinates in **decimal degrees plus the Maidenhead locator**; a Settings switch for degrees, minutes and seconds. Metric units only. |
+| Q65 | **The position never leaves the device in M2.** Sharing it over the mesh, and at what precision, is decided in M4. |
+| Q66 | **Our own NMEA parser**, host-tested: RMC, GGA, GSA and GSV, with each talker ID mapped to its constellation. TinyGPSPlus (named in ADR 0001) doesn't track the satellite list across constellations, which the Sky view needs. |
+| Q67 | The receiver keeps its **defaults** (all constellations, 1 Hz). No receiver settings. Time to first fix is measured and recorded here. |
+| Q68 | Debug aids: `gnss status`, and `gnss nmea on/off` to stream the raw sentences to the console (USB serial and Debug Console). Raw NMEA is never written to the card. |
+
+**Lesson (step 3):** the first probe also tried the pins swapped, driving the receiver's output line from the ESP32 for about a second. The receiver then went silent until a full power cycle (an ESP32 restart doesn't cut the Cap's power). Never drive GPIO 15.
+
+## Done when
+
+- The GNSS Service reads NMEA in the background whatever App is on screen, and a 3D Fix appears outdoors.
+- The GNSS App shows the Position and Sky views, both live.
+- The Status Bar shows the GNSS mark per Q61.
+- With no Wi-Fi, the clock is set from GNSS after the first Fix.
+- A Track records while the App is closed, survives the screen turning off, and opens as valid GPX on the PC.
+- Settings → GNSS Off stops it (and the Status Bar mark goes away); On brings it back.
+- Free heap stays above about 40 KB with GNSS, Wi-Fi, IRC on TLS and the UI running.
+
+## Work breakdown
+
+1. **Hardware check:** a `gnss probe` command reads the candidate UART pins and reports which carries NMEA, at what baud rate, and which talker IDs. Then the standby command (Q58) and a first time to first fix.
+2. **NMEA parser** (host-tested): checksum, RMC, GGA, GSA, GSV across constellations, merged into one GNSS state (Fix, position, time, satellites).
+3. **GNSS Service:** UART on its own task, the parser, `gnss status` and `gnss nmea`, Settings On/Off.
+4. **Clock from GNSS** (Q62), and the Status Bar mark (Q61).
+5. **GNSS App:** Position view, Maidenhead and coordinate formats (host-tested), then the Sky view.
+6. **Tracks:** the 5 s / 5 m rule and GPX writing (host-tested), background recording, Clean-up category.

docs/milestones/M3.md

@@ -0,0 +1,69 @@
+# M3 — Radio bring-up: the LoRa Scanner
+
+**Status:** done, tagged v0.6.0. Everything was checked on the device except one "Done when" item: Sweep was never tried against a known transmitter (see below). The listening hour heard nothing, so by Q104 **a reference Meshtastic node is a requirement for M4**.
+
+**Goal:** the LoRa radio on the Cap works, receive only: a Radio Service owns it and shares the SPI bus with the SD card safely, and a LoRa Scanner App shows what's on the air, either packets (Sniffer) or energy across the band (Sweep). Nothing in M3 can transmit. The mesh comes on top of this in M4 (receive) and M5 (transmit).
+
+**Hardware:** the Cap LoRa-1262 carries an SX1262 (868–923 MHz, +22 dBm) with an RP-SMA antenna. Pins, as in Meshtastic's board file for the Cardputer ADV: **NSS 5, RST 3, DIO1 (IRQ) 4, BUSY 6**, on the SPI bus shared with the microSD card (SCK 40, MISO 39, MOSI 14; card CS 12). Meshtastic uses DIO2 as the RF switch and DIO3 for a 1.8 V TCXO, marked optional. M5Stack's page adds an FM8625H antenna switch enabled by P0 of a PI4IOE5V6408 I/O expander on the internal I2C bus, address not given; Meshtastic doesn't mention it. Step 1 measures which is true.
+
+**No other LoRa device yet.** meshmap.net (2026-10-05) lists two Meshtastic nodes within 10 km of the desk and six within 30 km, with positions blurred by a few km; none is known to be in range. M3 needs none: it only receives.
+
+## Measured
+
+- **Internal I2C bus (8/9):** 0x18 (ES8311 codec), 0x34 (TCA8418 keyboard), **0x43 (PI4IOE5V6408, ID register 0xA2)**, 0x69 (BMI270 IMU).
+- **The SX1262 answers** on NSS 5, RST 3, DIO1 4, BUSY 6. Its version string reads `SX1261 V2D 2D02`, which SX1262 chips report too. **The 1.8 V TCXO works** on the first try; the radio is ready 38 ms after `begin`.
+- **The expander's P0 connects the antenna; it's required.** At power-on P0 is an input (direction 0x00, high-impedance 0xFF), and the receiver reads a flat **-111.9 dBm** at 869.525 MHz, BW 250 kHz: the chip's own floor, deaf. With P0 driven high, the noise floor is **-87 to -94 dBm**: the antenna hearing the room. So the Radio Service drives P0 high at boot (Q91).
+- **DIO2 doesn't change reception** (within ±2 dB over three runs, P0 high). It likely selects TX versus RX in the FM8625H; it stays the RF switch, as in Meshtastic.
+- **The noise floor at the desk is high** (-87 to -94 dBm, varying run to run), about 25 dB above thermal noise for 250 kHz. Something nearby is loud, possibly the Cardputer itself or the PC; Sweep (step 5) should show where it sits.
+- **Step 2:** presets, frequencies and the channel hash are checked against Meshtastic's source (`MeshRadio.h`, `RadioInterface.cpp`): LongFast and the default key give hash 8, MediumFast 31, as Meshtastic shows. Captures were checked with TShark 4.2.5: every LoRaTap field reads back. Wireshark ignores the spec's quarter-dB packet RSSI below 0 dB SNR, so packet RSSI is plain dBm.
+- **Step 3:** the DIO1 interrupt works (a 100 ms receive timeout wakes the task after 105 ms). While listening: four 1.7 MB uploads and Gemini pages to the card, no radio or card errors (the card refuses a write about once in five uploads with the radio asleep too; `put` now catches it, and issue #21 follows the cause). The ring takes 9.8 KB while listening; the radio task's stack peaks at 2.0 KB.
+- **No packets yet, and a loud desk.** Twenty minutes on LongFast and on LoRaWAN's three uplink frequencies (SF7, SF9, SF12): no packet and no header, valid or not. The noise floor reads -83 to -94 dBm, against -112 dBm with the antenna switched off: 20 to 30 dB lost to something nearby, not the screen and not the GNSS receiver. Preamble detections are false alarms at this noise level (more on an empty frequency, 869.0 MHz, than on LongFast).
+- **Step 4:** a Capture made on the device reads back in TShark field for field (time, frequency, SF, RSSI, SNR, payload). A Capture keeps the radio listening with the App closed; stopping it puts the radio back to sleep.
+- **Step 5:** a pass across 863–870 MHz (71 steps, the strongest of three RSSI readings at each, measured at 125 kHz) takes about 607 ms. At the desk the band is **flat at -100 to -102 dBm**, about 15 dB above the chip's own floor at 125 kHz, with a steady carrier at 863.2 MHz (-89 dBm at its strongest) and fainter lines elsewhere: broadband noise from nearby electronics rather than a transmitter. Sweep's waterfall takes 2.6 KB while shown; 91.9 KB free during a Sweep. The radio task's stack peaks at 1.9 KB.
+- **Outside, on battery (step 6).** The noise is no lower than at the desk: a Sweep floor of -96 to -99 dBm (median -97) with Wi-Fi on, -99 to -100 with Wi-Fi off, so Wi-Fi accounts for 2 or 3 dB. The same narrow peaks come back on every pass, at 863.2, 863.6, 864.4, 864.8, 865.9, 866.3, 867.8, 869.0 and 869.4 MHz (-88 to -91 dBm), several of them 400 kHz apart; 869.4 MHz is the lower edge of LongFast's channel. A source that follows the device outside and onto its battery is the device: **about 15 dB of the floor is the Cardputer's own** (issue #20). At SF11 that puts the weakest decodable packet near -114 dBm on LongFast, against about -130 dBm for a quiet receiver.
+- **The listening hour (step 6, Q104):** 20:33 to 21:34 on 2026-10-05, outside, on battery, LongFast, with a Capture running. **0 packets, 0 headers**, 0 radio errors; noise -85 to -87 dBm at 250 kHz throughout; 860 preamble detections, all false alarms. The Capture holds its 24-byte header and nothing else. No restart in 1 h 10 min.
+- **Floors (Q86):** with the radio listening, Wi-Fi and IRC connected over TLS, 52.6 KB free (lowest 22.7 KB during the TLS handshake, the dip accepted in G1). Without IRC, 93 KB.
+- **Receive only:** nothing in `src` or `lib` calls a transmit function.
+- **Cost:** RadioLib 7.8.1 and the probe add 23.6 KB of flash and 656 bytes of static RAM to the release firmware (1,679,843 bytes of 3,342,336). The whole milestone: 51.8 KB of flash (1,708,091 bytes), 365 tests (27 new).
+
+## Decisions (design round 2026-10-05)
+
+| # | Decision |
+|---|---|
+| Q89 | **M3 is the radio only:** Radio Service, Sniffer, Sweep. Notes and the File Browser (Q30) move out to issue #3 and a Notes issue, as a later side milestone. |
+| Q90 | **RadioLib**, pinned (ADR 0001). SX1262 on NSS 5, RST 3, DIO1 4, BUSY 6; DIO2 as RF switch; TCXO at 1.8 V tried first, falling back to the crystal (Meshtastic's `TCXO_OPTIONAL`). |
+| Q91 | Step 1 is `lora probe`: chip status and version, which oscillator setting worked, and an I2C scan of the internal bus for the PI4IOE5V6408. If present, its P0 is set high at boot (harmless) and DIO2 stays the switch. A wrong switch receives deaf, so compare noise floors. |
+| Q92 | A **Radio Service** owns the SX1262: driver, bus lock, IRQ task. The LoRa Scanner uses it in M3; the Mesh Service sits on top of it in M4. |
+| Q93 | Every radio transfer takes the shared bus lock (`SPI.beginTransaction`, as the card does). DIO1's interrupt only wakes the task; no SPI in the ISR. **Done when** a Gemini page streams to the card while the Sniffer receives, with no lost packets and no card errors (`lora status` counters). |
+| Q94 | **Receive only:** the Radio Service has no transmit function in M3. It doesn't exist, rather than being unused. |
+| Q95 | Sniffer defaults: **EU868 LongFast**, 869.525 MHz, BW 250 kHz, SF 11, CR 4/5, sync word 0x2B, preamble 16 (Q19). The other Meshtastic presets are offered, plus custom settings. |
+| Q96 | The Sniffer lists packets (time, RSSI, SNR, frequency error, length; hex dump on Enter) **and decodes the Meshtastic header**: the first 16 bytes are never encrypted (destination, sender, packet ID, hop limit and hop start, channel hash, next hop, relay node). Host-tested. Payload decryption is M4. |
+| Q97 | A Sniffer **Capture** is pcap with **LoRaTap** headers (link type 270), for Wireshark. Started by hand, Status Bar mark, its own Clean-up category, the 90% rule. |
+| Q98 | **Sweep** steps across the Region's band (863–870 MHz) in 100 kHz steps by default, reading instant RSSI: bars with peak hold, and a waterfall, Wi-Fi Tools style. Optionally CAD on the preset's frequency to tell LoRa traffic from noise. |
+| Q99 | Sweep takes the radio and pauses the Sniffer, visibly (Q18). From M4 it pauses the Mesh Service the same way. |
+| Q100 | The Sniffer runs while the App is open **or a Capture is recording**; otherwise the radio sleeps. From M4 the Mesh Service keeps it on. |
+| Q101 | **Status Bar:** a radio mark while receiving, flashing on each packet; muted during a Sweep. |
+| Q102 | Debug aids: `lora status` (settings, counters, last RSSI/SNR, noise floor), `lora probe`, `lora rx on/off` (packets on the consoles). Raw packets are never written to the card outside a Capture. |
+| Q103 | A ring of the **last 32 packets** in RAM (about 9 KB at full length); older ones are dropped unless capturing. IRQ task stack trimmed by measurement; RadioLib's flash and RAM measured in step 1 against the floors. |
+| Q104 | **Done when** (below) includes an hour of listening on LongFast by a window. Real packets heard become M4 test fixtures. If none are heard, M3 still closes, and a reference Meshtastic node (Q21) becomes a requirement for M4. |
+
+## Done when
+
+- `lora probe` reports the SX1262, its oscillator setting and the RF switch arrangement, and the result is written here.
+- The Sniffer receives on LongFast with the App open or a Capture running, and the radio sleeps otherwise.
+- Sweep shows the noise floor across 863–870 MHz, and a known signal (a remote key fob, a 868 MHz sensor, anything) stands out. *Half met: the floor and the device's own steady peaks show; no known transmitter was tried.*
+- The shared-bus test passes (Q93): a Gemini page to the card while the Sniffer receives, no lost packets, no card errors.
+- A Capture opens in Wireshark with LoRaTap fields.
+- The Status Bar mark follows Q101.
+- One hour of LongFast listening by a window has been run and its result recorded here. *Run outside, on battery.*
+- Free heap stays above the floors (Q86) with the Sniffer, Wi-Fi, IRC on TLS and the UI running.
+- Nothing in the firmware can transmit.
+
+## Work breakdown
+
+1. **Hardware check:** RadioLib in the build, `lora probe` (Q91), flash and RAM cost measured.
+2. **Meshtastic header and LoRaTap** (host-tested): header parsing, presets and their radio settings, pcap/LoRaTap writing.
+3. **Radio Service:** receive on its own task behind the bus lock, the packet ring, `lora status` and `lora rx`, the shared-bus test.
+4. **LoRa Scanner App, Sniffer:** the packet list, details, preset choice, Captures, Status Bar mark.
+5. **Sweep:** the RSSI sweep, bars and waterfall, pausing the Sniffer.
+6. **Listening hour** and the measurements above, recorded here.

docs/milestones/OTA.md

@@ -8,7 +8,7 @@
 |---|---|
 | Q52 | Two sources: **push over Wi-Fi** from the PC, and **from the SD card**. Pulling from Gitea releases is deferred. |
 | Q53 | **Signed Update Files** (ECDSA P-256 over SHA-256). The private key stays in `~/.config/roro9stack/`, and the firmware embeds the public key (ADR 0003). |
-| Q54 | The device **always listens** for pushes on the LAN while Wi-Fi is Connected, announced as `roro9stack-<id>.local`. |
+| Q54 | The device **always listens** for pushes on the LAN while Wi-Fi is Connected. *Revised in M2:* it was announced over mDNS as `roro9stack-<id>.local`; mDNS was removed to save RAM (it never crossed the dev box's routed network anyway). Pushes go to the IP shown in Settings → Firmware. |
 | Q55 | New firmware runs on **Probation**. It's confirmed once booted, UI drawn, Services started, 30 s without a crash, and Wi-Fi connected (if configured). Otherwise **Rollback**. A Toast reports either outcome. |
 | Q56 | **Downgrades are allowed**, with "older than the installed version" shown. |
 | Q57 | A valid push **installs right away**: progress screen, then reboot. The reboot waits for Text Entry to end, 60 s at most. |

docs/milestones/R1.md

@@ -0,0 +1,233 @@
+# R1 — Releases
+
+**Status:** in progress. CI and signed releases on Gitea (issue #5) are in place since 2026-10-06: every tag from v0.1.0 to v0.10.0 has its release. Updates from Gitea (issue #6) is built and checked on the device, on branch `gitea-updates`, not merged yet. The Issues App (#4) comes after.
+
+**Goal:** a tag is a release, built the same way every time and published where a device can find it.
+
+## CI and releases (issue #5)
+
+Until now the tests, the builds, the signing and the flashing all happened on one machine, through `scripts/ci.sh` and `scripts/flash.sh`. Nothing was published.
+
+### Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q151 | A push to `main`: the host tests (with their coverage). A push to another branch: nothing, its pull request is what runs (a branch with an open pull request ran twice, once for each). A pull request: the same and both builds; changes reach `main` through pull requests. A tag `v*`: all of it, then a release. (First: everything on every push, which rebuilt the firmware far more often than anyone looked at it.) |
+| Q152 | **CI signs.** The signing key is the repository secret `OTA_SIGNING_KEY`; a tag push makes a complete, signed release with no manual step (ADR 0008). |
+| Q153 | *Revised by Q188: there is one firmware.* The Debug Build is built in CI with a token of the runner's own, to prove it compiles, and **isn't published**: it would hand everyone its Debug Console token. |
+| Q154 | Pull requests from forks don't start a run. |
+| Q155 | A release carries `roro9stack-<version>.ota` (signed), `-factory.bin` for USB, `.elf.gz` to decode crashes, and `SHA256SUMS`. |
+| Q156 | Its text is the tag's message, what the files are, and the commits since the tag before. |
+| Q157 | No cache service to begin with: measure first. |
+| Q158 | Reproducible builds aren't needed for signing any more (Q152); not pursued here. |
+| Q159 | **The tags from before CI get their releases too**, v0.1.0 to v0.10.0, built from each tag's own sources by running the workflow by hand. |
+| Q160 | Actions is switched on for the repository. |
+| Q161 | **Changes reach `main` through pull requests, merged as "rebase, then a merge commit"**, the only style the repository allows: the branch's commits keep their messages, the merge commit marks the pull request, and what CI tested is what lands. No squash, no fast-forward. |
+
+### As built
+
+- **One workflow, `.gitea/workflows/ci.yml`, one job**, on the runner `runner0` (label `ubuntu`). The job asks for a `python:3.12-slim` container, installs git, a compiler, openssl and PlatformIO, and runs the same scripts as a developer's machine. No Docker inside the job.
+- **The cache is a Docker volume**, `roro9stack-pio`, mounted at `/pio`; the runner's `config.yaml` allows it under `container.valid_volumes`. A first run downloads about 1 GB and rebuilds the framework. Measured from the jobs' own start and end times: the first full run on an empty cache took 11.4 minutes (tests and both builds); the first run in a container, 8.1; a pull request now takes about 8.7 (tests, coverage and both builds), a release build alone 5.5, and a push to `main` (tests and coverage) 1.1. (An earlier version of this note said 17 minutes: that was the waiting time, not the job's.)
+- **No JavaScript actions**, so the image needs no Node and nothing is fetched from GitHub: the checkout is four git commands.
+- **`scripts/_docker.sh`** runs the command in place when `RORO_NO_DOCKER` is set (a CI job is already in a build container), and in the project's image otherwise. The Debug Build's token is made on the spot in CI and goes with the container.
+- **`scripts/release_build.sh <checkout> <out>`** builds a tag's own sources with today's tools, signs, verifies against the public key in those sources, and writes the files and the release's text. **`scripts/release_publish.py`** creates the Gitea release or completes it; run twice, it replaces what's there. Both run the same on a developer's machine.
+- **`scripts/ota_verify.py`** checks an Update File as a device does, on a PC.
+- **The job's own token** (`secrets.GITEA_TOKEN`) is enough to create a release and upload its files.
+- **Old tags.** v0.1.0 to v0.3.0 are from before the framework was rebuilt with our settings (ADR 0006) and can't link against a rebuilt one left in the cache: the release build puts the stock framework libraries back for them. v0.1.0 to v0.2.1 have no public key in their sources (Firmware Updates came with v0.3.0); their files are checked against today's.
+
+### How it went
+
+- **The runner's label took three tries.** Registered as `ubuntu://docker:ubuntu:resolute` and then as `ubuntu::docker://...`, Gitea took the whole string for the label's name; with the first, jobs ran on the runner's host itself. The first version of the workflow was written for that (plain shell, `docker run` for the build) and published v0.10.0 that way. `ubuntu:docker://docker.gitea.com/runner-images:ubuntu-latest` is the form that works.
+- **Gitea 1.27's API can't cancel a run that isn't finished**, only delete a finished one; switching Actions off and on for the repository doesn't either. Runs queued for a label that no longer exists stay queued until cancelled in the web UI.
+- **CI's image isn't byte-identical to a local build of the same tag** (same size, different bytes). Not pursued (Q158).
+
+## Updates from Gitea (issue #6)
+
+The device looks at the project's Gitea for a newer release, says so, and installs it on request, with the same signed Update Files, Probation and rollback as a push from the PC or an install from the card.
+
+### What the server gives (checked 2026-10-06)
+
+- **Its certificate** is Let's Encrypt, all ECDSA: leaf `git.twis.la` (renewed every few months, next expiry 2026-12-14) under the intermediate YE2, Root YE and ISRG Root X2, which X1 cross-signs. Pinning the leaf would ask a question at every renewal.
+- **The API** answers over HTTP/1.1, chunked: `releases/latest` is 3.2 KB (about 350 bytes of it matter), a list of ten releases is 33 KB.
+- **A download** is a direct 200 with `Content-Length` and no redirect; ranges work.
+
+### Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q162 | **Trust:** the firmware carries ISRG Root X1 and X2 and checks the server's chain and name against them, not the framework's bundle of about 130 CAs (ADR 0009). Shared with #4. If the server moves to another CA, the next firmware comes from the PC. |
+| Q163 | The Update File's own signature stays the real guard. A hijacked connection could hide a release or offer an older signed one, never install firmware that isn't ours. |
+| Q164 | The source, `git.twis.la` and `twisla/roro9stack`, is a constant in the firmware. A fork changes it, and has its own key. |
+| Q165 | **When:** on request in Settings > Firmware, and once a day in the background while Wi-Fi is up and the Clock is set (certificate dates need it). A setting, **Check for updates**, on by default. It installs nothing by itself; it skips quietly below the memory floor and never runs during an install. |
+| Q166 | A Toast, "Update v0.11.0 available: see Settings > Firmware", once per version per boot. |
+| Q167 | **The download goes straight into the inactive slot,** no card needed. A truncated or tampered file is refused after 160 bytes or at its end, and the running firmware is untouched. A failed download starts over. |
+| Q168 | A version that failed (rolled back) isn't announced again by the background check until a newer one exists; it can still be installed by hand. |
+| Q169 | **Older releases:** a list of the last ten, newest first, the running one marked. Installing an older one asks with a stronger warning. |
+| Q170 | Enter on a release shows its version, date, size and the tag message, with Install. |
+| Q171 | *Revised by Q188: there is no Debug Build, every firmware installs releases.* **Debug Builds** check and show the latest release, but don't install it: it would replace the Debug Build and its console (Q153: Debug Builds aren't published). Their updates come from the PC. |
+| Q172 | **Memory, as measured:** a TLS connection peaks at about 52 KB of heap, with or without checking the certificate, so it starts with 80 KB free (Q86's 20 KB spare on top), not 55 KB. **A check, list or install someone asked for makes IRC step aside** and come back after; the daily check never does, and with IRC connected it waits. (First: 55 KB and nothing else. With IRC connected a check left 3 KB and a download 836 bytes.) |
+| Q173 | Left out, each with its issue: installing automatically (#52), a release channel (#53), resuming a download (#54). |
+| Q174 | Ships as **v0.11.0**. Tested on the device with the real signed releases; a Debug Build command pretends the device runs an older version, so v0.10.0 counts as an update. |
+
+### Done when
+
+- A check, by hand or daily, tells the right thing: up to date, newer available, no network, bad certificate, no clock, too little memory.
+- A newer release installs from the Firmware page with no card and no PC, and the device restarts into it and confirms it.
+- A tampered or truncated download is refused and the running firmware keeps running.
+- The Older releases list shows ten, and installing one asks first.
+- A release that rolled back isn't announced again.
+- A Debug Build shows the latest release and doesn't install it.
+- The daily check never runs below the memory floor, during an install, or without a clock.
+
+### Work breakdown
+
+1. **Model** (host-tested): a streaming JSON scanner, the release list read from it, HTTP response heads and chunked bodies, URLs, which release counts as an update.
+2. **The connection:** the root certificates, an HTTPS client, a check and a list from the Update Service's task; console commands to try them.
+3. **The download:** an HTTPS source for the existing install path.
+4. **The screens:** the Firmware page's release rows, the release page, Older releases, the setting, the daily check and its Toast.
+5. **Checks on the device**, recorded here.
+
+### As built
+
+- **`lib/release`** (host-tested): a streaming JSON scanner, the release reader built on it, HTTP heads and chunked bodies, URLs, and the decisions (which release is an update, whether to announce it, which download URLs are taken). A list of ten releases is 33 KB of JSON and costs a few hundred bytes of memory, because nothing is kept but the path.
+- **`HttpsGet`** (`src/platform`): one GET, the answer read as a stream, redirects not followed. **`GiteaReleases`** keeps the latest and the list. **The Update Service** serves the requests on its own task (about 5.4 KB of its 7 KB stack at the peak) and installs through the install path that already existed, with an HTTPS source in place of the card or the TCP port.
+- **The daily check** is scheduled from the Update Service's tick: Wi-Fi up, the Clock set, no Probation, nothing else going on, memory for a connection. The day it last succeeded is kept in flash.
+- **A version that failed** (rolled back) is remembered as `ota_failed`, and isn't announced again by the daily check.
+- **The screens:** the Firmware page's Latest release and Older releases rows, a release page with the tag's message, and the install dialog.
+- **Debug Builds** get knobs to try what can't be tried otherwise: `update pretend`, `probe`, `damage` and `daily`.
+- **The first message,** `... available: see Settings > Firmware`, was cut at 48 bytes by the notification's own limit; it now reads `v0.11.0 is out: see Settings > Firmware`.
+
+### Checks on the device (2026-10-06, Debug Builds of branch `gitea-updates`)
+
+| Check | Result |
+|---|---|
+| Host tests | 456 pass |
+| Check and list against the live server | The certificate is accepted against the two embedded roots; `releases/latest` read; a list of ten (33 KB) streamed |
+| Servers that must be refused | github.com, example.com, expired.badssl.com, self-signed.badssl.com, wrong.host.badssl.com, untrusted-root.badssl.com and the router: each "isn't accepted" or a TLS error |
+| A download cut short at 800,000 bytes | Refused, "update file too short"; the running firmware untouched |
+| One byte flipped in the signature | Refused after 160 bytes, "bad signature"; the image isn't read further |
+| One byte flipped in the image | Downloaded in full, refused at its end, "image corrupted (hash mismatch)" |
+| The real v0.10.0, from the console and then from the screen | Downloaded, restarted, confirmed on Probation: the slot table read `v0.10.0, valid` both times. The Debug Build was pushed back from the PC after each |
+| The screens | Latest release (checking, then `(current)` or `(new)`), the release page with the tag's message, Older releases with ten rows, the install dialog (Cancel by default, Back cancels), the progress screen at 28% |
+| IRC connected, before the hold | A check left 3 KB of heap; a full download, 836 bytes |
+| IRC connected, with the hold | The lowest free heap during a full download: 38 KB. IRC reconnected afterwards (its counters kept growing) |
+| The daily check | It ran by itself, announced `v0.10.0 is out: see Settings > Firmware` once; with IRC connected (68 KB free) it didn't run |
+| Speed | 1.9 MB in about 46 s, 40 KB/s, over the guest Wi-Fi at -65 dBm; not investigated further |
+
+**Not checked:** the certificate's **name** on its own. Connecting by IP makes the server end the handshake before it shows its certificate, so that test proved nothing; the library sets the name it verifies, and OpenSSL on the PC refused the wrong name against the same chain. A failed daily check retrying, the clock not being set, the release that failed before not being announced (host-tested, not on the device), and the hold when IRC isn't connected but Gemini holds memory.
+
+**Limits worth knowing:**
+- **With IRC connected for days, the daily check doesn't run.** It would have to take IRC down to make room. Opening Latest release does.
+- **A server that changes CA can't be reached** until a firmware carrying the new root comes from the PC (ADR 0009).
+- **No resuming:** a broken download starts over (#54).
+- **A key press during the hold:** Back on the Firmware page while a check is going doesn't cancel it.
+
+**Two slips during the checks:** a blind sequence of keys on the Firmware page opened the SD card's install dialog (the page keeps its selection between visits); it was cancelled with Back, nothing installed. And my port-polling while waiting for a restart took the Debug Console's only client slot, which made the first install attempt look like a failure.
+
+## One firmware: the Debug Console in every build (issue #68)
+
+The issue asked for a token that could be set, so that Debug Builds could be published. The design round ended somewhere simpler: no Debug Builds. The console is in every firmware, off until switched on, with a token that belongs to the device (ADR 0010, which supersedes part of ADR 0004).
+
+### Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q188 | **One firmware,** with the Debug Console and the test commands compiled in. The `cardputer-adv-debug` environment, `RORO_DEBUG`, the `+debug` version and `scripts/debug_flags.py` go; CI builds one firmware. Revises Q153 and Q171. |
+| Q189 | **Off by default,** and off when the stored setting is missing or invalid. Off, nothing listens and no memory is used: the task and the 4 KB ring exist only while it's on. |
+| Q190 | **Settings → Debug Console:** the switch, where to connect, the token, "New token", "Type a token". It stays on across restarts and in Safe Mode. **`DBG` in the Status Bar** while it listens, bright with a client connected. |
+| Q191 | **The device makes the token** the first time the console is switched on: 100 bits as 20 characters of Crockford's base32, shown in groups of four. It can be replaced by one typed by hand, of at least 16 characters. Case and dashes don't count. |
+| Q192 | **USB serial can set it up:** `debug on`, `debug token <value>`, `debug token new`, over USB only; `debug status` and `debug off` from anywhere. `scripts/flash.sh --debug` gives a device the developer's token. The token is never printed. |
+| Q193 | **Challenge and answer:** the device sends 16 random bytes, the client their HMAC-SHA256 keyed by the token. Five wrong answers in a row close the console for a minute, with a Notification. **Old clients and old firmwares don't talk to each other:** accepted, this far from v1 and with one user. |
+| Q194 | `rdbg.py` takes the token from **`-t`/`--token`**, then **`$RORO_DEBUG_TOKEN`**, then `~/.config/roro9stack/debug-token`. |
+| Q195 | **The test commands are in every build** (`crash abort`, `crash wdt`, `update pretend`, `update damage`, `lora inject`, `sd fill`, `loop spin`, `wifi ip … try`). `update install … force` goes: there's nothing left to protect. |
+
+### As built
+
+- **`lib/debug`** (host-tested, 9 tests): the token maker, tidying what a person types, HMAC-SHA256 on the project's own SHA-256 (checked against RFC 4231), the answer to a challenge (the same vector as `rdbg.py`'s), a comparison that takes the same time whatever it's given, and the pause after five wrong answers, right across the clock's wrap.
+- **Two settings,** `DebugConsole` and `DebugToken`, with the others: validated, and invalid stored values count as missing.
+- **The console's task and ring come and go with the setting.** `Console::openRing` allocates the ring; switching off closes the socket, frees it and ends the task. `tick` follows the settings once a second, so a switch off and on again takes a second or two.
+- **Measured against the two builds it replaces:** 1,881,799 bytes of flash and 54,700 of static RAM. The release build was 1,851,387 and 54,612 (so 30 KB more flash and 88 bytes more RAM); the Debug Build was 1,874,887 and 58,780 (4 KB of RAM back: the ring is no longer a static array).
+- **The listener is asked whether it listens.** The framework's `begin()` returns nothing and fails without a word; the task now checks, says so on the console, and tries again every two seconds.
+- **`debug off <seconds>`** closes the console and brings it back by itself: the only way to try its closing and reopening from afar, since switching it on is for the device and the cable only.
+- **`scripts/rdbg.py`** answers the challenge, and fetches a release's ELF from Gitea when a crash names a version that isn't in `.pio/elves/`.
+
+### Checks
+
+| Check | Result |
+|---|---|
+| Host tests | 468 pass (456 before) |
+| The firmware builds | One environment, 1,881,799 bytes of flash used |
+| Pushed over Wi-Fi to a device running a Debug Build | Installed, restarted; the update port answers and **port 2323 refuses connections**: off by default |
+| Switched on at the device (Settings → Debug Console) | A token is made and shown. Its first drawing, in bold at normal size, was misread once: it is now at twice the size, in two lines, and `O`, `I` and `L` are taken for `0` and `1` |
+| A login with `scripts/rdbg.py` | The challenge is answered; `info`, `screenshot` and the backlog work |
+| `DBG` in the Status Bar | There while the console is on, bright while a client is connected (screenshots) |
+| `debug on` and `debug token` over the console | Refused: `over USB serial only` |
+| Six logins with a wrong token | Five are refused, a second apart; the sixth, and the right token after it, get `locked`. After a minute the right token works again. The console's own log and a Notification say so |
+| Three `crash abort` in a row | **Safe Mode**, with the console reachable: `info` works, `ls /` says `not available in Safe Mode`. `rdbg.py crash` decodes the backtrace to `runCommand` at the `abort()` line. `reboot` leaves Safe Mode |
+| An update over Wi-Fi with the console on | The setting and the token survive: the console is back by itself after the restart |
+| `debug off` over the console | The client is dropped and port 2323 refuses connections; the update port still answers |
+| `debug off 2`, 10 times in a row, then 15 | It came back each time, a second after the pause. Free heap dips by about 270 bytes for each connection the device closes and **is all back two minutes later** (107.2 KB before, 103.2 right after 15, 107.0 at two minutes): TCP holds a closed connection that long. Not a leak, though it looked like one for an hour |
+| Memory, console on with a client | 108 KB free (the Debug Build it replaces: 104 KB). In Safe Mode: 178 KB free |
+
+**One false alarm:** after the tests the console "wouldn't come back on". It was off: the setting had been left off by `debug off`, and the page's "Switch it on?" dialog opens on **Cancel**, so Enter twice leaves it off. Nothing was lost.
+
+**Not checked:** `scripts/flash.sh --debug` over USB (no device on USB here); "New token" and "Type a token" from the page (the code paths are the ones `debug token` uses, which need the cable); the Toast itself on screen (the console is closed while it shows; its Notification is in the log); free memory with the console off, which only the serial port could say (the static figures above are the evidence); fetching a release's ELF, which needs a crash on a released version.
+
+## CI that doesn't rebuild the world (issue #74)
+
+A pull request's run took over seven minutes, a tag's thirteen and a half. The goal: a firmware build under a minute.
+
+### Where the time went (run 81, a pull request, 2026-10-06)
+
+| Step | Time |
+|---|---|
+| Tools (apt, pip) | 15 s |
+| Check out | 2 s |
+| Host tests and coverage | 55 s |
+| **The firmware** | **358 s** |
+| of which: CMake configuring ESP-IDF | 87 s |
+| of which: compiling ESP-IDF's libraries | 171 s |
+| of which: our own build (the Arduino core, the libraries, `src/`) | 91 s |
+
+A tag's run did the firmware step, then built the same commit again for the release: twice 356 s.
+
+### Why the framework was rebuilt every time
+
+The framework is rebuilt with our SDK settings (ADR 0006), and the rebuilt libraries stay in the toolchain volume. But the platform decides whether they match by reading **`sdkconfig.defaults` in the project folder**, whose first line carries a hash of the settings. That file is generated, and not in git. A fresh checkout has none, so the platform concluded "different settings", **reinstalled the framework and rebuilt it**: 260 seconds, at every run, to arrive at the libraries that were already there. On a developer's machine the file is simply still there from the last build, which is why nobody saw it.
+
+### What changed
+
+| Change | Effect |
+|---|---|
+| **The file is kept in the volume, inside the libraries it describes** (`framework-arduinoespressif32-libs/.roro-sdkconfig.defaults`), copied into the checkout before a build and back after one that passed. The platform still checks its hash against `platformio.ini`: changed settings rebuild, as they must. Kept there and not beside them, it disappears when the libraries are reinstalled, so it can't describe libraries that are gone | 358 s to 92 s |
+| **The version is no longer a `-D` on every compiler command line.** `scripts/version.py` writes `lib/version/src/version_generated.h` (not in git, written only when it changes), read by one file. Before, every commit recompiled everything, on a developer's machine too, and no cache could have helped | A rebuild with nothing changed: 77 s to 13 s, locally |
+| **PlatformIO's build cache** (`PLATFORMIO_BUILD_CACHE_DIR`, SCons's CacheDir) in the volume, for the firmware of pull requests: objects by the signature of their sources and command line | 92 s to 26 s, with a new version and one changed file |
+| **ccache for the host tests.** They are built with coverage counters, and the build cache would return objects without their `.gcno` files; ccache keeps both | 49 s to 33 s. What's left is PlatformIO starting 51 test programs |
+| **A tag builds its firmware once**, in the release step | minus 6 minutes |
+| PlatformIO and gcovr in a virtual environment in the volume | a few seconds |
+
+**A release compiles its own sources from nothing:** it reuses the rebuilt framework (the platform checks the hash) but not the build cache, so no published file contains an object that came from another commit's build.
+
+### Measured (a development machine, fresh copies of the tree, the same volume)
+
+| | Before | After |
+|---|---|---|
+| The firmware, fresh checkout, nothing cached for it | 358 s | 82 s (it fills the cache) |
+| The firmware, fresh checkout, a new version and one file changed | 358 s | **27 s** |
+| Host tests and coverage | 49 s | 33 s |
+| Rebuilding locally with nothing changed | 77 s | 13 s |
+
+### Measured on the runner (pull request #76, 2026-10-07)
+
+| Run | Tools | Tests and coverage | The firmware | The whole job |
+|---|---|---|---|---|
+| Before (run 81) | 15 s | 55 s | 358 s | 434 s |
+| The first with the new workflow: no mark yet, the framework is rebuilt once more and the caches fill | 16 s | 59 s | 354 s | 431 s |
+| The next commit (only the workflow changed) | 10 s | 36 s | **51 s** | **100 s** |
+| The same commit again | 10 s | 36 s | **18 s** | **66 s** |
+
+In the 51-second run, 245 objects came from the cache and 43 were compiled: `version.cpp`, as expected, and all 42 files of `src/`, which had not changed. In the run after it, all 290 came from the cache. So the objects of `src/` made by the run that rebuilt the framework were not reusable by a normal run, and those of a normal run are: the two-pass build that rebuilds the framework compiles `src/` with something different on its command line. It costs one 51-second run after each framework rebuild, which is rare; I did not look for what differs.
+
+The firmware step with everything cached is 18 seconds: the libraries are downloaded and unpacked (4 s), the dependency scan (5 s), fetching 290 objects, the link and the image (the last 11 s). A pull request that changes a few files should land between that and 51 seconds.
+
+**What it costs:** the build cache grows by about 40 MB a run (each linked firmware is kept) and is started again past 3 GB; ccache is held to 1 GB.

docs/milestones/S1.md

@@ -0,0 +1,204 @@
+# S1 — System basics
+
+**Status:** the three planned items are done: the SD driver fix in v0.6.1 (issue #21, ADR 0007), fixed IPv4 settings in v0.7.0 (issue #7), the System App in v0.8.0 (issue #11). v0.8.1 adds the resting main loop (issue #40) and the GNSS pause for the radio's noise (issue #20, still open for the 11 dB that remain). Still open in the milestone: #39, following the SD driver upstream.
+
+**Goal:** the device works on any network, the card can be trusted, and you can see what the system is doing. A side milestone, like G1.
+
+## Fixed IPv4, DNS and NTP (issue #7)
+
+Not every network has a DHCP server: a lab bench, a direct link to a router, a network where addresses are handed out by hand. Until now every Saved Network used DHCP, DNS always came from DHCP, and the NTP server was `pool.ntp.org`, hard-coded.
+
+**IPv4 only.** IPv6 isn't part of this, now or as a planned follow-up.
+
+### Decisions (design round 2026-10-05)
+
+| # | Decision |
+|---|---|
+| Q105 | The IP setting is **per Saved Network**: *Automatic* (DHCP, as before) or *Fixed*, with its own address, prefix and gateway. New networks start Automatic. |
+| Q106 | The subnet is entered as a **prefix length** (`24`), with the mask shown next to it. |
+| Q107 | The **gateway is optional**: left empty, the device talks to its own subnet only. |
+| Q108 | **DNS is global:** two servers in Settings, used on every Fixed network. On Automatic networks DHCP's DNS is used, unless **"Always use my DNS"** is on. |
+| Q109 | DNS defaults: **9.9.9.9** (Quad9), then **1.1.1.1** (Cloudflare). |
+| Q110 | **NTP is global:** two servers in Settings, names or addresses, defaulting to `pool.ntp.org` and `time.cloudflare.com`. NTP servers offered by DHCP are used first. GNSS still outranks NTP for the clock. |
+| Q111 | What's typed is checked, host-tested in `lib/wifi`: an address is four numbers from 0 to 255; a prefix is 1 to 30; the address isn't the subnet's network or broadcast address; the gateway is inside the subnet and isn't the device's own address. Refusals say why. |
+| Q112 | Addresses are typed in the line editor, limited to digits and dots. |
+| Q113 | Enter on a Saved Network opens **its page** (IP, Address, Prefix, Gateway, Forget) instead of asking to forget it. Settings > Wi-Fi gains DNS servers, "Always use my DNS" and NTP servers. The Status row opens **connection details**: address, mask, gateway, DNS and NTP in use, and where each came from. |
+| Q114 | A change applies **at once**: the network in use reconnects with the new settings. No automatic way back; the keyboard still works if Wi-Fi is cut. |
+| Q115 | Console: `wifi status` shows address, gateway, DNS, NTP and their sources; `wifi ip <ssid> dhcp`, `wifi ip <ssid> <address>/<prefix> [gateway]`, `wifi dns <a> [b]`, `wifi ntp <a> [b]`. Debug Builds: `wifi ip … try 60` goes back to the previous setting after 60 s unless confirmed with `wifi ip keep`. |
+| Q116 | Left out: checking whether the address is already taken, and per-network DNS. |
+
+The SDK already allows 3 NTP servers and 3 DNS servers and can take NTP servers from DHCP (`CONFIG_LWIP_SNTP_MAX_SERVERS=3`, `CONFIG_LWIP_DHCP_GET_NTP_SRV=y`), so the framework isn't rebuilt for this.
+
+### Done when
+
+- A Saved Network set to Fixed joins with that address, mask and gateway, and the device reaches the internet (IRC, Gemini, NTP) through the DNS servers from Settings.
+- Set back to Automatic, it gets its address from DHCP again.
+- With "Always use my DNS" on, an Automatic network resolves through the servers from Settings.
+- The NTP servers from Settings set the clock.
+- Wrong entries are refused with a reason, in Settings and on the console.
+- Connection details show what's in use and where it came from.
+- Tested on `knbg-guests` with 10.39.39.12 (the device's DHCP lease) and 10.39.39.13 (free: the device is alone on that network).
+
+### Measured (2026-10-05 and 06, on `knbg-guests`)
+
+The network is 10.39.39.0/24, gateway 10.39.39.1; DHCP gives 10.39.39.1 as DNS and offers no NTP server.
+
+- **Fixed 10.39.39.12/24** (the device's own lease) and **Fixed 10.39.39.13/24**, gateway 10.39.39.1: the device joins with that address, DNS is 9.9.9.9 and 1.1.1.1 from Settings, and a Gemini page loads (name resolution, routing, TLS). On .13, .12 no longer answers.
+- **A wrong gateway** (10.39.39.254) on a 60 s trial: the device stops answering from another subnet, and comes back by itself with the previous setting.
+- **Back to Automatic:** 10.39.39.12 by DHCP again, DNS 10.39.39.1 from DHCP.
+- **"Always use my DNS"** on an Automatic network: DNS becomes 9.9.9.9 and 1.1.1.1; switched off, the device joins again and has DHCP's DNS back.
+- **NTP:** `pool.ntp.org` answers; set to `time.cloudflare.com` alone, that one answers within 25 s.
+- **Refusals**, on the console and in Settings: the network's own address, a gateway outside the subnet, a prefix of 31 or 99, 10.39.39.300, an unknown network, a DNS name where an address is needed, a host name with an underscore.
+- **In Settings:** the network's page pre-fills Fixed with the address, prefix and gateway in use; leaving the page applies it; connection details show each value and where it came from.
+- **Not tested:** NTP servers offered by DHCP (this network offers none), and a Fixed network with no gateway.
+
+### Work breakdown
+
+1. **IPv4 logic** (host-tested): parsing and formatting addresses, prefix and mask, the checks of Q111.
+2. **Storage:** the IP setting in each Saved Network; DNS, "Always use my DNS" and NTP in Settings.
+3. **Wi-Fi Service:** apply it when joining; DNS and NTP; `wifi status` and the console commands.
+4. **Settings:** the network page, the DNS and NTP rows, connection details.
+5. **Tests on the device**, recorded here.
+
+## System Monitor (issue #11)
+
+Every milestone so far was driven by measurements, heap floors, stack sizes, TLS dips, that needed a Debug Build and a computer. The System App shows them on the device, in any build.
+
+### Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q117 | An App of its own, **System**, in release builds too. Read-only. |
+| Q118 | Four views, switched with Tab: **Overview** (CPU per core, memory, network, battery), **Tasks**, **Memory**, **System**. |
+| Q119 | Sampled once a second. A task's share is its run time over the last second; a core's load is 100 % minus its idle task's share. |
+| Q120 | **History only while the App is open:** two minutes at one sample a second, about 1 KB. The system already keeps what matters afterwards: the lowest free heap since boot and each task's lowest free stack. |
+| Q121 | **Bytes are counted per service:** IRC, Gemini, the Debug Console and Firmware Updates add what they read and write to a shared counter. The network view shows the connection details, each service's bytes in and out, and the signal strength. |
+| Q122 | Tasks: name, core, share, state and lowest free stack, sorted by share; `s` cycles the sort (share, stack, name). **Under 512 bytes of stack left shows in the warning colour.** |
+| Q123 | Memory: free heap, lowest since boot, largest free block, and a two-minute graph of free heap **with the floors of Q86 drawn as lines** (55, 40 and 20 KB). |
+| Q124 | System: uptime and why it last started, firmware and both app slots, chip temperature and CPU frequency, battery voltage and percentage, SD usage and write faults, the radio's and the GNSS receiver's state. |
+| Q125 | `info` and `tasks` are split into a **snapshot** that the console and the App share; the arithmetic (shares from two samples, sorting, the stack warning) is host-tested. |
+| Q126 | Left out: acting on tasks, an event log, exporting snapshots to the card. |
+| Q127 | The main loop uses about 81 % of a core. The App shows it; fixing it is issue #40, not part of #11. |
+
+The App has five views, not four: Q121's network view is one of its own (Overview, Tasks, Memory, Network, System).
+
+### Measured (2026-10-06)
+
+- **Traffic counters are exact.** A Gemini fetch of a 164,970-byte page counts 164,986 bytes in (the page and its 16-byte header line) and 42 out (the 40-character URL and CRLF). A 1,797,760-byte upload counts 1,798,123 in for the Debug Console, commands included.
+- **The Memory view shows a TLS dip as it happens.** Starting IRC and a 165 KB Gemini fetch together: free heap falls from about 100 KB through the three floors to a low of 12.1 KB, then settles near 50 KB. That's the dip accepted in G1 (Q86).
+- **A run-time counter only moves when its task is switched out.** FreeRTOS adds to a task's run time at the context switch. The main loop takes the samples, and with core 1 to itself it's never switched out: its counter said 2 % while the core's idle task had 0 %. So the task that samples gets what's left of its core. With that: **the main loop uses 100 % of core 1 at rest** (issue #40 said 81 %, an average since boot).
+- **`tasks` on the console** sampled twice inside one command at first, a quarter second apart, and showed the loop at 1 %: it was asleep in the command's own wait. It now samples, lets the loop run for a second, and prints.
+- **Low stack, flagged:** `IDLE0` (232 bytes left), `IDLE1` (328 to 352) and `spk_task` (256 to 264), all the framework's own tasks.
+- **Cost:** 15.6 KB of flash for the App and the counters (1,742,723 bytes, release). Nothing while it's closed; about 2 KB of history and samples while it's open.
+
+## The main loop rests (issue #40)
+
+The loop polled the keyboard, ticked the Services, ran the consoles and redrew when needed, then came straight back: 50,000 passes a second, and core 1 100 % busy with the device idle and the screen off.
+
+Nothing needs that. The keyboard controller buffers key events; the consoles and the radio have their own tasks or interrupts; no Service asks for a tick more often than every 50 ms. So after each pass the loop now rests: **5 ms with the screen on, 20 ms with it off**, and not at all during a serial file transfer (`sd put`), which reads its bytes from the loop. Safe Mode's loop rests 5 ms too. Debug Builds have `loop spin on|off` to bring the old behaviour back for comparison.
+
+### Measured (2026-10-06, Debug Build, Wi-Fi connected, GNSS on, on USB power)
+
+| | Spinning | Resting |
+|---|---|---|
+| Passes a second, screen off | 50,160 | 50 |
+| Core 1 load, screen off | 100 % | 1 % |
+| Passes a second, screen on (Launcher) | 1,203 | 167 |
+| Core 1 load, screen on | 62 % | 10 % |
+| Chip temperature at rest, settled | 38.3 C | 34.3 C |
+| A 1.8 MB upload over the Debug Console | about 230 KB/s | 288 KB/s |
+
+- Still working at this pace: GNSS (a 3D Fix, 22 satellites), a Gemini fetch (52 KB), the upload read back by SHA-256, the Sweep (still 606 to 610 ms a pass), the radio's DIO1 interrupt.
+- **Not measured:** the current drawn (no meter on the battery line), and how typing feels on the real keyboard: a key now waits up to 5 ms for the loop, 20 ms if it's the one that wakes the screen.
+- **The radio's noise floor didn't move** (-97 to -99 dBm at 125 kHz either way): the spinning loop wasn't the source (issue #20).
+- **Not done:** real sleep. The framework is built without power management (`CONFIG_PM_ENABLE` is off), so an idle core only halts until the next interrupt. Automatic light sleep would need the framework rebuilt with it, Wi-Fi in modem sleep, and the USB serial port's behaviour checked. A next step if battery life calls for it.
+
+## The radio's noise: the GNSS receiver (issue #20)
+
+M3 found the LoRa radio's noise floor about 15 dB above what the chip hears alone, and that the source travels with the device. Which part? Debug Builds got a self-test, `lora noise test`: it changes one thing at a time, Sweeps the band eight passes (568 readings), records the median as the floor, and puts the thing back. It runs on the device by itself, because one condition switches Wi-Fi off, and `lora noise report` prints the result afterwards.
+
+### Measured (2026-10-06, indoors, on USB power, dBm at 125 kHz)
+
+| Condition | Floor |
+|---|---|
+| Antenna switched off (the chip alone) | -117 |
+| Antenna on, GNSS in standby | -106 |
+| Antenna on, GNSS running (as shipped) | -98 |
+
+- **The GNSS receiver, while it runs, raises the floor by 8 dB.** Three runs: -98 or -99 with it running, -106 in standby, every time. On LongFast (250 kHz) the Sniffer's own reading goes from about -93.5 to -101.5 dBm.
+- **It's the receiver working, not its serial line:** with one NMEA sentence a second instead of twenty (`PCAS03`), the receiver still tracking, the floor stays at -98.
+- **Nothing else moves it by more than 1 dB**, with GNSS running or in standby: the main loop spinning or resting, the CPU at 240, 160 or 80 MHz, Wi-Fi on or off, the screen on or off, the radio chip's regulator as DC-DC or LDO, its receive gain boosted or not.
+- **11 dB remain** between the antenna connected with GNSS quiet (-106) and the chip alone (-117). It comes in through the antenna and none of those switches changes it: the surroundings, or parts of the Cardputer that can't be switched off. Not separated: that needs another place, or the antenna on a cable away from the case.
+- M3's quick check had GNSS at "1 or 2 dB": it read one frequency for a few seconds, in a noisier spot. The median over the band is the better measure.
+
+### What the firmware does about it
+
+**Settings > Pause GNSS for LoRa**, off by default: while the LoRa radio listens or sweeps, the GNSS receiver waits in standby, and wakes when the radio goes back to sleep (a Fix again after about 7 s here). Never during a Track. The GNSS App says "GNSS is paused" meanwhile. `gnss quiet on|off` on the console.
+
+It's off by default because GNSS on by default was decided in M2 (Q58), and from M4 the radio listens all the time: then "pause while listening" means GNSS mostly off, which is a decision about position, the clock and Tracks, for M4's design round (issue #23).
+
+## The Shell (issue #67)
+
+The console's commands could only be typed on a PC: over USB, or over Wi-Fi with the Debug Console. A device in a bag, or on a network that is down, could not be asked anything. The Shell is an App that runs the same commands on the device's own screen and keyboard.
+
+### Decisions (design round 2026-10-07)
+
+| # | Decision |
+|---|---|
+| Q204 | **An App, "Shell", in the Launcher**, in every firmware: its commands already work over USB for anyone holding the device. |
+| Q205 | **Trusted like USB serial**, not like the network: `debug on` and `debug token` work from it, as they do in Settings. The token is never shown. |
+| Q206 | *Revised the same day, after trying it.* **It shows the replies to its own commands, and only those.** The console knows who each line is printed for (`Console::Origin`): a command run from the Shell prints as the Shell's, and so does what answers it later from another task, which notes who asked and takes it back when it prints (`ls`, `tasks`, `du`, `cp`, `update check`, `sd list`, `screenshot`, `gemini get`). What USB or the Debug Console asked for, and the system's own lines, are not the Shell's. **Ctrl+b shows everything** instead. The first version kept whatever was printed in the ten seconds after a command, which was a guess, and a noisy one. |
+| Q207 | **Nothing while it's closed.** Open, a 4 KB ring of the console's and up to 4 KB of lines; both go when the App is left, with the list of commands for Tab. |
+| Q208 | Enter runs the line; Fn with up and down recalls the last 16; Alt with up and down scrolls back. **Tab completes** the command, **every word of it** *(the first only, at first)*: `lora st` gives `lora status`, `gnss track ` lists `start  stop`, `key ` its eleven names. The words come from the firmware's `help` text, read as it is written, so a new command completes without a table to keep. *(Added the same day)* **past the command, a path on the SD card**: a folder keeps its slash to go on from, a file completed whole gets a space, several candidates are listed. Whatever the case typed, the name's own is taken, since the card doesn't tell them apart. After a file command the first slash is understood (`cat no` is `/no`). A name with a space in it isn't completed. |
+| Q209 | *Revised the same day.* **`rm` is Unix's, with a question.** A folder needs `-r`, here and over the consoles (where `rm <folder>` used to remove it with what was in it). In the Shell, a file, or a folder with something in it, is asked about unless `-f` (`-rf`, `-r -f`); an empty folder with `-r` goes without a word; what `rm` would refuse anyway, it refuses itself. Over the consoles nothing is asked: scripts delete as before. **`screenshot [seconds]`** saves the screen as a PNG in `/screenshots`, now or after a pause, since from the Shell "now" is the Shell. `get`, `put`, `coredump get` and `reset` answer `Debug Console only`. *(Added the same day)* **`*` and `?` in a name**, for `ls`, `du`, `rm`, `cp` and `mv`, here and over the consoles: `rm /notes/*.txt`, `cp /gnss/2026-10-0?.gpx /backup`. In the last part of the path only, any case, as the card has it. It is the same command once for each name matched, in the name's order; `cp` and `mv` then need a folder that exists to put them in. Over 64 matches is refused whole, as is none. In the Shell `rm` with a pattern asks **once**, with the count. |
+| Q210 | Commands are echoed as `> command` into the console, so a session reads the same from afar. **A token being set is not echoed.** |
+| Q211 | **Not in Safe Mode**, which starts no Apps: issue #77. |
+| Q212 | Its keys are a table in `app_keys.h`, so the help panel and the website have them; a page in the user guide. |
+| Q213 | *Added the same day.* **An App's name with a capital opens it:** `Irc`, `Wifi`, `Gnss`, `Gemini`, `Lora`, `Storage`, `Notes`, `Shell`, `System`, `Settings` (the App's id, up to its first dash). From the Shell, without going back to the Launcher, and from the consoles too. The capital says "an App": every command of the firmware is in small letters. Tab completes them. |
+
+### As built
+
+- **`ShellApp`** (`src/apps/shell_app.cpp`), with its model host-tested in `lib/apps_model/src/shell_log.h`: lines arriving in pieces, the 4 KB limit, the words of every command out of the `help` text (Apps' names included), and Tab.
+- **Who a line is for:** `Console::As` marks the calling task as printing for the Shell while it lives, and `Console::origin()` lets a command that answers later carry that to wherever it prints. The console has a second ring for the Shell, which gets the lines marked so, or everything.
+- **The Shell hands its lines to the main loop**, which runs them like the consoles' commands. See below for why.
+- **`info` says which App is in front** (`app: Shell`): so that a hand driving the device from afar can look before it types.
+- **`screenshot`** writes the PNG a row at a time with no buffer: 8-bit indexed colour, the 256 colours of RGB332 as the palette, the pixels in one stored deflate block (`lib/files/src/png_rgb332.h`, 4 tests). 33,383 bytes for the 240 x 135 screen. A Toast says so once it is on the card, so the Toast is never in the picture.
+- **The `help` text lost its shorthand** (`update check | list | status` is written out), since Tab reads its words from there: `|` between two commands, `on|off` between two words, three spaces before the description. The Shell's own words (`clear`, `quit`, `key`'s names) are added in the same notation.
+- **Tab on a path** reads the folder on the storage task while the main loop waits, so it is bounded: 400 entries looked at, 24 candidates given back, and `...` after the list when there were more.
+- **A pattern** is matched in `lib/files/src/file_names.h` (`globMatch`, host-tested), and the names it matches are lined up as so many commands, which the main loop runs one after the other as each finishes. `cancel` empties the line-up. 2000 entries looked at, 64 matches at most.
+- **Cost:** 21 KB of flash, 96 bytes of static RAM. Open: 7 KB of heap (107.6 KB free before, 100.7 with it open, 106.1 after leaving).
+
+### What went wrong while building it
+
+**The device crashed, and the test sent a message to an IRC channel.** The first version ran a command from inside the key handler. Driven from the Debug Console, that is: the main loop, a remote command, `key select`, the App manager, the Shell, `runCommand` a second time, the file command, and `printf` under all of it. The main loop has under 2 KB of stack to spare; `rm` on a folder went past it. The crash report decoded to exactly that chain.
+
+The device restarted into the Launcher, and the test script, which did not look, went on typing. Its next Enter opened IRC, which connected, and a few lines later it typed "No" into a channel and pressed Enter. One word, sent to real people, that can't be taken back.
+
+Two changes came of it. The Shell now **queues** its line and the main loop runs it, at the same stack depth as a console's command. And `info` reports the App in front, which the test script now checks before every line it types.
+
+### Checks on the device (2026-10-07, driven over the Debug Console with `key`)
+
+| Check | Result |
+|---|---|
+| Open it from the Launcher, type `ls /`, Enter | The folders are listed |
+| Tab on `in` | `info  install` is shown and the line stays; on `u` it becomes `update `; on `l`, `log  ls  lora  loop` |
+| Up | The line before comes back |
+| `screenshot` | `/screenshots/20261007-104357.png`, 33,383 bytes. Fetched and decoded on the PC: 240 x 135, indexed, every chunk's CRC right, the pixels the Shell's screen |
+| Output | With a Debug Console client connecting and disconnecting for every key, the Shell shows the commands and their replies and nothing else: `info`, `ls /` (answered by the storage task), `tasks` (answered a second later) |
+| `rm` on a folder, without `-r` | Refused, the folder stays |
+| `rm -r` on an empty folder | Removed, no question |
+| `rm -r` on a folder with files | Asks; Cancel leaves it. `rm -rf` removes it without asking |
+| `rm` on a file | Asks; Delete removes it |
+| Tab on a path | `ls /no` becomes `ls /notes/`, and again, with one note in it, the note's whole name and a space. `ls /g` lists `gemini/  gnss/`. `cat no` becomes `cat /notes/`. `rm -r /CAP` becomes `rm -r /captures/`. `ls /zz` stays as it is |
+| Tab past the first word | `lora st` becomes `lora status `; `gnss tr` becomes `gnss track ` and Tab again lists `start  stop`; `key ` lists its eleven names; `upd` becomes `update ` and lists `check  list  status  install` |
+| `ls` with a pattern | `ls /gt/*.txt` the five files, `ls /gt/*2*` the one, `ls /gt3/*6?.txt` ten of seventy. `ls /g*/x`: refused, a pattern goes in the last part |
+| `cp /gt/file-000?.txt /gt2`, `du /gt2/*1*` | Five copies; one size |
+| `rm /gt2/*` in the Shell | "The 5 that match /gt2/\*": Cancel leaves the five. `rm /gt3/*6?.txt`, Delete: ten gone, sixty left. `rm -f /gt2/*`: gone without a question |
+| `rm /gt/*` where one match is a folder | The files go, the folder stays (no `-r`) |
+| No match, and seventy | `rm: error nothing matches`; `rm: error more than 64 match: a narrower pattern, please`, and all seventy still there |
+| `No`, Tab, Enter | Completes to `Notes ` and opens Notes. `Shell` from the Debug Console opens the Shell |
+| `screenshot 4`, then Home | The picture, taken four seconds later, is of the Launcher: the pause works, and the Toast isn't in it |
+| `quit` | Back to the Launcher, and the memory comes back |
+| The help panel in the Shell | Its keys, then the ones that work everywhere |
+
+**Not checked:** Ctrl+b and the Alt scroll, which `key` can't press (no modifiers): the filter itself is host-tested, the key that flips it is not; the real keyboard altogether; the Toast after a screenshot, which was published but not looked at; and `mv` with a pattern and `cancel` in the middle of a line-up, which share their code with `cp` and `rm` but were not run. The main loop's lowest free stack after all of it: 1.8 KB, where it was.

docs/milestones/U1.md

@@ -0,0 +1,46 @@
+# U1 — Look and feel
+
+**Status:** in progress. The help key (issue #69) is merged; the website's key tables generated from the same lists (issue #72) are in a pull request. Screen recording (#17) and the rest of the milestone are not started.
+
+**Goal:** the interface is consistent and uncrowded: the same thing is done the same way on every screen, and the 135 pixels of height go to content.
+
+## The help key (issue #69)
+
+Every screen used to say something about its keys, differently: a footer of abbreviations in one place (`c x v:paste r:name d:del n:new i:info s:sort`), a line under a text field in another (`Enter: save   \`: cancel`), `Tab: sky` in a corner, and nothing at all in several. About 30 such strings, each costing a line of a small screen, and none of them complete.
+
+### Decisions (design round 2026-10-07)
+
+| # | Decision |
+|---|---|
+| Q196 | **Fn+h, on every screen,** text fields included (Fn is held, so nothing is typed). **`?` too, outside Text Entry.** |
+| Q197 | It opens **a panel over the content area**, titled with where you are: the screen's own keys, then an "Everywhere" group (Back, Home, the arrows, the help key). The arrows scroll it; any other key closes it and is not passed on. |
+| Q198 | **Each App answers "what are your keys right now?"** for the state it is in; pages, viewers, dialogs and text fields answer for themselves, with shared lists for dialogs, lists and text entry. The lists are constants; the panel's rows exist only while it is open. |
+| Q199 | **Every hint that names a key goes,** text fields included. What stays is state: `REC 12 points`, `LOG 42`, `sort:signal`, `typing`/`saved`, what is waiting to be pasted, the Sweep's floor. Messages were reworded where they named a key ("v pastes a copy of…" is "Copied …: paste it where you like"). |
+| Q200 | **The first-start Setup keeps its hints,** and is the one place that does: someone in their first minute doesn't know the help key yet. It tells them about it on its first and last screens. |
+| Q201 | **Loud everywhere else:** the user guide opens with it, the FAQ has it first, and a device set up before this firmware gets one Toast, once: "Fn+h: the keys of any screen". |
+| Q202 | `key help` over the consoles. Generating the website's key tables from the same lists is a follow-up, not this issue. |
+| Q203 | The key and the panel first, host-tested; then one App at a time, declaring its keys and losing its hints in the same step; then every screen looked at on the device. |
+
+### As built
+
+- **`Key::Help`** from the key mapper: Fn+h in both modes, `?` only outside Text Entry (`lib/input`, 3 tests).
+- **`App::help()` and `App::helpTitle()`** (`lib/core/src/app.h`), `KeyHelp` rows and `HelpModel` (`key_help.h`). The **App manager** opens the panel, appends the "Everywhere" group, and while it is open takes every key: nothing reaches the App, Home included. It closes when the App changes (5 tests).
+- **Every App declares its keys by state:** the Launcher, IRC (chat, settings, a field), Wi-Fi Tools (4 views), GNSS, Gemini (page, saved page, address, answer, dialogs), the LoRa Scanner (4 views), Storage (browse, details, a name, the viewer's 6 modes, the editor, Maintenance, busy), Notes (list, editor, a file name), System (5 views), Settings (menu, text, choice, and the Wi-Fi, Firmware and Debug Console pages with their own states), Setup and the widget demo.
+- **The hints are gone** from all of them. The footers that remain say state only.
+- **It costs** 8.5 KB of flash and 40 bytes of static RAM.
+
+### Checks
+
+| Check | Result |
+|---|---|
+| Host tests | 476 pass (468 before) |
+| On the device, `key help` and a screenshot | The Launcher and all nine Apps, and these states: Storage scrolled, System's tasks, a Settings text field, Wi-Fi Tools' networks. The panel is titled with the scope, lists the right keys, scrolls, and closes on Tab |
+| The one-time Toast | `notification: Fn+h: the keys of any screen` on the first start after the update |
+
+### One source for the device and the website (issue #72)
+
+The lists first lived in each App's `help()`, as code. They are now **data, in one file**: `lib/core/src/app_keys.h`, 52 constant tables, each under a comment `// id: Title`. An App's `help()` picks the table of the state it is in. `site/tools/gen_dev_docs.py` reads the same file and writes `site/data/keys.toml`; the `keys` shortcode shows a screen's tables on its guide page, and `/guide/keys/` shows all of them. The Site job fails when the data file is out of date, or when a page asks for a table that doesn't exist, and it now runs when `app_keys.h` changes. A key added to an App shows up on the website without anyone editing a page.
+
+Three rows lost their second wording on the way, since a table is constant: GNSS's `Tab` and `r`, and the Scanner's `c`, now say both things they do ("record a Track, or stop it") instead of the one that applies. The guide pages keep their written tables too, where they say more than a key list can; those can still drift, and the generated ones under them are the reference.
+
+**Not checked:** the real Fn+h and `?` on the keyboard (the mapper is host-tested; the device was driven with `key help`); the Setup screens, which only a device that was never set up shows, so their new text has not been seen on a screen; and the states that need something to happen first (a dialog, a copy in progress, a Gemini prompt, a packet's details): their lists were read against the key handling, not looked at.

docs/milestones/W1.md

@@ -0,0 +1,170 @@
+# W1: Website
+
+**Status:** phases 1 to 3 (home, Install and Downloads; the user guide; how-tos and the FAQ) and the devlog are live at roro9stack.net; phase 4 (the developer docs) is in a pull request. Issue #12.
+
+**Goal:** a public home for the project at **roro9stack.net**, separate from the blog (stories) and from Gitea (developers): what it is, how to install it, how to use each App, and the docs.
+
+The home page was designed on a canvas in a Claude chat (a dark and a light theme, built on the device's own 256-colour palette, pixel-notched corners, DM Mono and Hanken Grotesk). It is the starting point, not the final copy: it has to say only what the firmware does today.
+
+## What was found while planning (2026-10-06)
+
+- `roro9stack.net` already points at the server that hosts Gitea. Plain HTTP redirects to HTTPS; HTTPS has no certificate yet, which is the server's side to set up.
+- **Release downloads from Gitea carry no CORS header,** so a browser can't fetch the factory image from another origin as things are. Gitea is behind Caddy, which can add the header (below).
+- Zola can read JSON from a URL at build time (`load_data`), so the home page's "latest version" can come from the Gitea API.
+- There is no Gitea wiki: the design's "Wiki" links would 404.
+- The blog is published by pulling its repository on the web server and running `zola build`. The site does the same.
+
+## Decisions (design round 2026-10-06)
+
+| # | Decision |
+|---|---|
+| Q175 | The site lives in this repository, in `site/`, so the documentation is built from `docs/`, `CONTEXT.md` and the README instead of being copied. |
+| Q176 | **Zola,** like the blog. The design becomes a template, its tokens CSS custom properties. Dark and light follow the visitor's setting, with a visible switch. No JavaScript except the flasher's. |
+| Q177 | Domain: **roro9stack.net.** The blog stays at experiments.twis.la. |
+| Q178 | **Publishing is the blog's way:** the web server pulls `main` and runs `zola build`; that part is the maintainer's. *(Since issue #79, CI asks the server to do it: see "Published by CI" below.)* Changes reach `main` through pull requests as everywhere. **CI is split:** a dedicated `site` job builds the site (`zola build`) when `site/`, `docs/`, `README.md` or `CONTEXT.md` change, and the firmware tests and builds skip a change that touches nothing else. A change that touches both runs both. |
+| Q179 | Phases, each its own pull request: **1.** the CI split, the home page, an Install page with the browser flasher, downloads and the changelog. **2.** a user guide page per App. **3.** how-tos and the FAQ. **4.** developer docs generated from the repository. |
+| Q180 | **A browser flasher** (ESP Web Tools), **without copying the firmware.** Caddy, in front of Gitea, adds `Access-Control-Allow-Origin: https://roro9stack.net` (and `Vary: Origin`) to GET and HEAD on `/twisla/roro9stack/releases/download/*` and `/api/v1/repos/twisla/roro9stack/releases*`: both are public already. The Install page asks the API for the latest release in the browser, finds the asset ending `-factory.bin`, and gives ESP Web Tools a manifest built on the spot, so it offers a new release as soon as it exists, with no rebuild. The library is **vendored** into `site/static/` (Apache-2.0), not loaded from a CDN. The file's SHA-256 is shown on the page. Chrome or Edge on a desktop only; other browsers, and visitors without JavaScript, get the `esptool` steps on the same page. |
+| Q181 | Docs for the latest version only. The changelog is the Gitea releases, read at build time. |
+| Q182 | English only. |
+| Q183 | The FAQ starts from real questions: the README, and issues labelled `kind/docs`. |
+| Q184 | Fonts are **self-hosted** (no request to a third party). The hero keeps the design's illustrations, labelled as illustrations, and a section of **real device screenshots** is added. |
+| Q185 | **The site says only what the firmware does today.** Planned features are marked as planned, with their milestone. The mesh messenger is **planned**: the LoRa Scanner listens, nothing is sent. |
+| Q186 | Left out, each with its issue: a Gemini capsule mirror (#57), French (#58), docs per version (#59), search (#60). |
+| Q187 | The site has no version of its own. Contact is **contact@roro9stack.net,** and the issue tracker. |
+
+## The design, reviewed
+
+Kept as designed: the layout, the tokens, the nine App cards (their facts check out against the code: Probation 3 minutes, Safe Mode after 3 crashes, 60 seconds of typing before an update restarts the device).
+
+Changed before it ships:
+
+- **Install, not Download, is the first action.** Downloads are for developers; a visitor wants to try it.
+- **A "what you need" strip:** Cardputer ADV, the Cap LoRa-1262 (only the radio needs it), a microSD card, Wi-Fi. And a plain status line: the version, and what isn't there yet.
+- **The mesh card and the hero** no longer promise sending and reading mesh messages.
+- **The latest version is read from the API,** not typed.
+- **"Wiki" is replaced by Docs.** The updates section gains what v0.11.0 added: the device installs releases from the project's server itself.
+- **An independence line:** not affiliated with or endorsed by M5Stack or Meshtastic.
+- **No cookies, no analytics, no third-party requests,** said on the page (fonts self-hosted).
+- **The keyboard focus ring** is invisible on the notched buttons: `clip-path` clips an outline. Another way to show focus is needed.
+- **The wordmark SVGs** carry an embedded C2PA content-credentials block: stripped from the site's copies.
+
+## Done when (phase 1)
+
+- Pushing a change under `site/` runs the `site` job and not the firmware tests; a firmware change runs the firmware jobs and not the site's.
+- The home page renders in both themes, at phone width, with the keyboard, and says nothing the firmware doesn't do.
+- The latest version on the page is the latest release.
+- The browser flasher installs the latest release on a Cardputer ADV from Chrome (tried by hand), the page shows the file's SHA-256, and the `esptool` steps are on the same page.
+- A release published after the site was built is the one the Install page offers.
+- The home and Downloads pages make no request to another origin, and the Install page only asks git.twis.la.
+
+## Work breakdown
+
+1. **CI split:** a `site` workflow, path filters on the firmware workflow.
+2. **The skeleton:** `site/` with the tokens, fonts, base template and the theme switch.
+3. **The home page,** from the design, with the changes above.
+4. **Install and downloads:** the flasher with its manifest built in the page, the `esptool` steps, the changelog. Needs the Caddy headers on the Gitea host (the maintainer's side); the page is tested against them once they're in.
+5. **Checks,** recorded here.
+
+## As built (phase 1)
+
+- **CI is split.** `ci.yml` (the firmware) has `paths-ignore: site/**, docs/**, README.md, CONTEXT.md` on pushes to `main` and on pull requests. `site.yml` runs `zola check` and `zola build` with a Zola pinned by its checksum, then `site/tools/check_site.py`, when those files change. Gitea's own source (v1.24, read, not run against the 1.27 server) shows that path filters count as matched for tag pushes, so a tag still releases. A change that touches both runs both.
+- **The build output** goes to `public/` at the root of the repository, not into `site/`: `output_dir = "../public"` in `site/config.toml`, so `zola build` in `site/` and `zola --root site build` from the root agree, and git ignores `/public/`.
+- **The site** is in `site/`: `config.toml`, templates (base, home, install, downloads, 404), `data/` for the App cards and the screenshots' captions, `static/` (stylesheet, theme switch, fonts, wordmark, icons, real screenshots, the vendored flasher). `site/README.md` says how to build it and what the server needs.
+- **The home page** follows the design. Changed from it: the hero and the mesh card promise nothing that isn't built (the mesh messenger is a "planned" card), an Install button first, a status box, a "what you need" row, a section of real screenshots, the updates section says the device installs releases itself, an independence line and a statement about cookies and third-party requests in the footer, the latest version read from the Gitea API at build time, and the nav's Wiki replaced. The two hero drawings are generated by `site/tools/make_illustrations.py` (a port of the design's scripted shapes) as inline SVG.
+- **The focus ring.** `clip-path` clips outlines, so a focused notched control drops its notches and shows square corners and its ring.
+- **The Install page** asks the API for the latest release in the browser, builds the ESP Web Tools manifest as a blob, shows the version, size and SHA-256, and only ever hands the flasher a download from the project's own server for this repository. The flasher library (ESP Web Tools 10.4.0, Apache-2.0) is vendored, trimmed to the ESP32-S3. Fonts (DM Mono, Hanken Grotesk, SIL OFL) are self-hosted.
+- **The Downloads page** lists the last 30 releases with their files, read at build time.
+- **The wordmark SVGs** from the design carried an embedded C2PA content-credentials block; it is removed from the site's copies.
+
+## As built (phase 2, the user guide)
+
+- **`/guide/`** is a section of 11 pages, `site/content/guide/`, each with `template` from the section's `page_template` and an order from `weight`: the basics (keys, Launcher, Status Bar, first start, the card), then one page per App (LoRa Scanner, GNSS, Gemini, IRC, Wi-Fi tools, Notes, Storage, System), Settings and Updates. Pages with real screenshots list them in `extra.screens`, looked up in `data/screens.toml`.
+- **Facts come from the README, the milestone documents and the Apps' own source** (key handlers, labels, the Status Bar's drawing code), not from memory. Some wording was corrected against the source while writing: the Track folder is `/gnss/tracks`, the reasons a Track won't start, what the Status Bar shows.
+- **Not covered:** the mesh messenger (planned), the debug console and Debug Builds beyond a pointer to the README. How-tos and the FAQ are phase 3.
+
+## As built (the devlog)
+
+Not one of the planned phases: the blog's seven roro9stack posts, imported into `site/content/devlog/` and shown in the site's own style, with the **Blog** link in the navigation and the footer replaced by **Devlog**. The posts' text, tone and structure are unchanged; what changed:
+
+- **Links:** the posts' links to each other point to `/devlog/<same name>/`, and one link to an unpublished work-in-progress post became plain text. Each post keeps its old directory name, so the old URL `/<name>/` maps to `/devlog/<name>/`.
+- **The posts' parts** (the sign, the cast, the steps, asides, folded sections, diagrams, captions) are shortcodes in `site/templates/shortcodes/`, restyled in `static/css/devlog.css`: the site's palette, notched boxes, DM Mono and Hanken Grotesk. The two older posts about other subjects (a vinyl remote, a ZFS rescue) stay on the blog.
+- **The 17 diagrams are inline SVG**, and carried `<style>` blocks and `style` attributes that the site's Content-Security-Policy refuses. Their rules moved to `static/css/devlog-diagrams.css` (one block per diagram, plus colour classes for what the attributes did), and a diagram's minimum width is a class, not a style attribute. The Caddy policy needs no change.
+- **The diagrams' four colours** (red, green, yellow, accent) are defined for `.devlog` on the site's RGB332 grid, one value for each theme.
+- **Links between posts:** every post's reference to another ("the last post", "the first post", the milestone lists) is a link to it. `check_site.py` now also checks every link inside the site, and its #fragment: a broken one fails the Site job. External links are checked by `zola check` run by hand (without `--skip-external-links`, which CI uses); its only complaints today are line-range and heading anchors on Gitea, which Gitea resolves in the browser.
+- **An Atom feed** at `/devlog/atom.xml`, linked from every devlog page.
+- **Checked** in Chromium with the production CSP applied to every response: the index and the seven posts, at 1100 and 390 px, no policy violation, no broken image, no sideways scroll; `check_site.py` 24 pages, 0 problems.
+
+## Checks (2026-10-06)
+
+| Check | Result |
+|---|---|
+| The Site workflow's own commands, in a clean container with the pinned Zola | `zola check` clean, build and page checks pass |
+| `tools/check_site.py` | 4 pages, 0 problems: titles, descriptions, a language, every image with alt text, every local file referenced exists, nothing loaded from another origin |
+| Browser tests (Chromium, 16 checks) | All pass: no request to another origin from the home, Downloads and 404 pages; no horizontal scroll at 1280 and 390 px; a visible focus ring on a notched button; the Install page reads the latest release, shows its version, size and SHA-256, builds a blob manifest naming an ESP32-S3 factory image at offset 0, and loads only git.twis.la; a download on another host is refused; the real server (no CORS header today) makes the page fall back to the esptool steps |
+| The pages looked at | Home in dark and light, at desktop and phone width; Install; Downloads |
+| `esptool` against the real v0.11.0 factory image | An ESP32-S3 image, bootloader at 0x0, partition table at 0x8000: flashing at offset 0 is right. The command's syntax was checked, not a flash |
+
+**Not checked:**
+- **Flashing a real Cardputer from Chrome.** It needs the device on a machine with a browser; the page's flasher logic is tested, the flashing itself isn't.
+- **Caddy's headers** on the real server (not applied yet), and **HTTPS on roro9stack.net** (the name resolves, the certificate isn't there).
+- **The CI split on a change that touches only `site/` or `docs/`.** This pull request touches both the workflows and the site, so it runs both; the first docs-only pull request will show it.
+- Firefox and Safari rendering, screen readers, and a printed page.
+- The unverified wording in the Install text is kept to what's known: nothing about how long flashing takes, or what the screen shows in download mode.
+
+## As built (phase 3, how-tos and the FAQ)
+
+- **`/howto/`** has eight short recipes: when flashing fails, find your files on the SD card, install an update from the card, use a network without DHCP, record a Track, capture LoRa packets for Wireshark, read Gemini pages offline, and what to do when a connection says "not enough memory". **`/faq/`** is one page of questions with a list at the top. Both use the guide's templates (`guide-index.html`, `guide-page.html`, now generic: the page's parent section gives the eyebrow, the title and the pager).
+- **The FAQ starts from the README** and from the problems the project met (Q183): the flash troubles and the memory limit are the two that were hit most. The issues labelled `kind/docs` turned out to be design rounds for the mesh, not user questions, so they gave nothing to answer.
+- **Every step comes from the README, the milestone documents or the Apps' source.** The privacy answer says plainly that the device contacts the project's server once a day for the update check (on by default, one switch to turn it off).
+- **Linked from the guide's index,** not the navigation, which stays short.
+
+## As built (phase 4, the developer docs)
+
+- **`/dev/`** has four sections: **Debug Builds and the Debug Console** (first, and the longest: Debug Builds, the Console and its protocol, files and screenshots, driving the UI, crashes and Safe Mode, and the command reference), **Build, test and release** (the README's build, CI and flash sections, and how an update works, with the update file, the four ways in and Probation drawn), **Decisions** (the ADRs) and **Milestones** (the plans).
+- **Generated from the repository, not copied by hand:** `site/tools/gen_dev_docs.py` writes the ADR pages, the milestone pages, the README's sections, and the command reference, which is read from the firmware's own `help` text in `src/main.cpp` and then the README's table of what each command does. Zola can't read outside its own folder (not even through a symlink), so the generated pages are **committed**, and the Site workflow runs `gen_dev_docs.py --check` and fails when one is out of date; it now also runs when `src/main.cpp` changes, because the command list lives there. The server's `pull; zola build` is unchanged.
+- **Left out on purpose:** the M0 and M1 milestone documents and `CONTEXT.md` (the glossary) describe Wi-Fi monitoring, which the site does not publish. They stay in the repository.
+- **The Debug Console pages were written against the source and the live console:** the protocol (the token line, the banner, the 4 KB backlog, one client, 8 queued commands, 240-byte lines, `denied` after a second) and the replies shown were checked on a Debug Build, v0.11.0-3, over Wi-Fi. Not run: `crash abort`, `crash wdt` and Safe Mode, which are described from ADR 0005 and the code.
+- **Found while writing it:** the README's table lacked the `gnss` commands (rows added); piping commands into `rdbg.py` returns before the replies unless the input stays open (documented, not changed); `update install` on a Debug Build needs `force` (documented).
+
+## Published by CI (issue #79, design round 2026-10-07)
+
+Q178 left publishing to the maintainer: a merge, then a command typed on the web server. It was forgotten often enough.
+
+| # | Decision |
+|---|---|
+| Q214 | **A plain ed25519 key with a forced command**, not a certificate: one line in the web server user's `authorized_keys`, `restrict,command="/full/path/to/the/refresh"`. `restrict` takes away the terminal and every forwarding. A certificate could carry the same and an expiry date, at the price of a CA to keep and a key to sign again each time: too much for one key and one command. |
+| Q215 | **The CI sends no command.** The server runs the forced one whatever is asked for, so there is nothing to keep secret about it and nothing a leaked key could choose. The full path is written once, on the server (a command over SSH doesn't get the user's login `PATH`). |
+| Q216 | Four secrets: `SITE_DEPLOY_KEY`, `SITE_DEPLOY_HOST` (or `host:port`), `SITE_DEPLOY_USER`, and **`SITE_DEPLOY_KNOWN_HOSTS`**, the server's host key: the job connects to that server or to nothing. None of them is in the repository, which is public. |
+| Q217 | `from="<the runner's address>"` on the same line: the key works from the runner only. |
+| Q218 | **The last step of the Site workflow**, after the build and the checks, on a push to `main` only. A pull request never reaches it, and the secrets are given to that step alone. |
+| Q219 | **After a release too.** The Install page asks Gitea for the latest release when it is opened, but the home page and Downloads read it when the site is built: so the release workflow refreshes the site once the release is published. |
+| Q220 | A refresh that fails makes the run red, with what the server's script printed: it has to exit with an error when it fails. |
+| Q221 | Two refreshes at once are the server script's to refuse or queue (`flock`). |
+| Q222 | The key is a file only while the step runs, in the job's container, as the signing key is. |
+
+### As built
+
+- **`scripts/site_refresh.sh`** is what both workflows run: it writes the key and the host key to a temporary folder, connects with no configuration but its own line (`-F none`, strict host key checking, that one key, no command), and removes them. With none of the four secrets it does nothing and says so (a fork, or a repository without them); with only some it fails.
+- **`scripts/site_deploy_keygen.sh`** makes the key pair once, in `~/.config/roro9stack/`, and prints the `authorized_keys` line and what goes in each secret. It never prints the private key.
+- **The server's script** should start like this, for Q220 and Q221:
+
+  ```sh
+  #!/bin/sh
+  set -e
+  exec 9>/tmp/rororefresh.lock
+  flock -w 120 9
+  ```
+
+### Checks (2026-10-07, against an SSH server in a throwaway container)
+
+| Check | Result |
+|---|---|
+| The refresh | The forced command runs as the server's user; the script ends with `site refresh: done` |
+| The same key, asking for `id; cat /etc/passwd` | The refresh runs instead; what was asked for is only handed to it as text |
+| A terminal | Refused: `PTY allocation request failed` |
+| `scp` with the key | Nothing is copied |
+| Another host key in the secret | `Host key verification failed`, the run fails, nothing is sent |
+| The server's script exits with an error | So does the step |
+| No secrets at all; only one of the four | Does nothing and says so; fails and says which are needed |
+
+**Not checked:** the real web server and the runner, which wait for the key to be installed: whether the runner reaches the server's SSH port is the first thing the first run will tell. Port forwarding, which `restrict` switches off, was not tried. `from=` was not tried either.

lib/SD/library.json

@@ -0,0 +1,7 @@
+{
+  "name": "SD",
+  "version": "3.3.12",
+  "description": "roro9stack's copy of Arduino-ESP32's SD library (Apache-2.0), shadowing the framework's. Only sd_diskio.cpp is changed (marked \"roro:\"): it records why a write failed and resends a block the card rejects. See issue #21.",
+  "frameworks": "arduino",
+  "platforms": "espressif32"
+}

lib/SD/src/SD.cpp

@@ -0,0 +1,134 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "vfs_api.h"
+#include "sd_diskio.h"
+#include "ff.h"
+#include "FS.h"
+#include "SD.h"
+
+using namespace fs;
+
+SDFS::SDFS(FSImplPtr impl) : FS(impl), _pdrv(0xFF) {}
+
+SDFS::~SDFS() {
+  end();
+}
+
+bool SDFS::begin(uint8_t ssPin, SPIClass &spi, uint32_t frequency, const char *mountpoint, uint8_t max_files, bool format_if_empty) {
+  if (_pdrv != 0xFF) {
+    return true;
+  }
+
+  if (!spi.begin()) {
+    return false;
+  }
+
+  _pdrv = sdcard_init(ssPin, &spi, frequency);
+  if (_pdrv == 0xFF) {
+    return false;
+  }
+
+  if (!sdcard_mount(_pdrv, mountpoint, max_files, format_if_empty)) {
+    sdcard_unmount(_pdrv);
+    sdcard_uninit(_pdrv);
+    _pdrv = 0xFF;
+    return false;
+  }
+
+  _impl->mountpoint(mountpoint);
+  return true;
+}
+
+void SDFS::end() {
+  if (_pdrv != 0xFF) {
+    _impl->mountpoint(NULL);
+    sdcard_unmount(_pdrv);
+
+    sdcard_uninit(_pdrv);
+    _pdrv = 0xFF;
+  }
+}
+
+sdcard_type_t SDFS::cardType() {
+  if (_pdrv == 0xFF) {
+    return CARD_NONE;
+  }
+  return sdcard_type(_pdrv);
+}
+
+uint64_t SDFS::cardSize() {
+  if (_pdrv == 0xFF) {
+    return 0;
+  }
+  size_t sectors = sdcard_num_sectors(_pdrv);
+  size_t sectorSize = sdcard_sector_size(_pdrv);
+  return (uint64_t)sectors * sectorSize;
+}
+
+size_t SDFS::numSectors() {
+  if (_pdrv == 0xFF) {
+    return 0;
+  }
+  return sdcard_num_sectors(_pdrv);
+}
+
+size_t SDFS::sectorSize() {
+  if (_pdrv == 0xFF) {
+    return 0;
+  }
+  return sdcard_sector_size(_pdrv);
+}
+
+uint64_t SDFS::totalBytes() {
+  FATFS *fsinfo;
+  DWORD fre_clust;
+  char drv[3] = {(char)(48 + _pdrv), ':', 0};
+  if (f_getfree(drv, &fre_clust, &fsinfo) != 0) {
+    return 0;
+  }
+  uint64_t size = ((uint64_t)(fsinfo->csize)) * (fsinfo->n_fatent - 2)
+#if _MAX_SS != 512
+                  * (fsinfo->ssize);
+#else
+                  * 512;
+#endif
+  return size;
+}
+
+uint64_t SDFS::usedBytes() {
+  FATFS *fsinfo;
+  DWORD fre_clust;
+  char drv[3] = {(char)(48 + _pdrv), ':', 0};
+  if (f_getfree(drv, &fre_clust, &fsinfo) != 0) {
+    return 0;
+  }
+  uint64_t size = ((uint64_t)(fsinfo->csize)) * ((fsinfo->n_fatent - 2) - (fsinfo->free_clst))
+#if _MAX_SS != 512
+                  * (fsinfo->ssize);
+#else
+                  * 512;
+#endif
+  return size;
+}
+
+bool SDFS::readRAW(uint8_t *buffer, uint32_t sector) {
+  return sd_read_raw(_pdrv, buffer, sector);
+}
+
+bool SDFS::writeRAW(uint8_t *buffer, uint32_t sector) {
+  return sd_write_raw(_pdrv, buffer, sector);
+}
+
+SDFS SD = SDFS(FSImplPtr(new VFSImpl()));

lib/SD/src/SD.h

@@ -0,0 +1,55 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#ifndef _SD_H_
+#define _SD_H_
+
+#include "FS.h"
+#include "SPI.h"
+#include "sd_defines.h"
+
+namespace fs {
+
+class SDFS : public FS {
+protected:
+  uint8_t _pdrv;
+
+public:
+  SDFS(FSImplPtr impl);
+  ~SDFS();
+  bool begin(
+    uint8_t ssPin = SS, SPIClass &spi = SPI, uint32_t frequency = 4000000, const char *mountpoint = "/sd", uint8_t max_files = 5, bool format_if_empty = false
+  );
+  void end();
+  sdcard_type_t cardType();
+  uint64_t cardSize();
+  size_t numSectors();
+  size_t sectorSize();
+  uint64_t totalBytes();
+  uint64_t usedBytes();
+  bool readRAW(uint8_t *buffer, uint32_t sector);
+  bool writeRAW(uint8_t *buffer, uint32_t sector);
+};
+
+}  // namespace fs
+
+#if !defined(NO_GLOBAL_INSTANCES) && !defined(NO_GLOBAL_SD)
+extern fs::SDFS SD;
+#endif
+
+using namespace fs;
+typedef fs::File SDFile;
+typedef fs::SDFS SDFileSystemClass;
+#define SDFileSystem SD
+
+#endif /* _SD_H_ */

lib/SD/src/sd_defines.h

@@ -0,0 +1,25 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#ifndef _SD_DEFINES_H_
+#define _SD_DEFINES_H_
+
+typedef enum {
+  CARD_NONE,
+  CARD_MMC,
+  CARD_SD,
+  CARD_SDHC,
+  CARD_UNKNOWN
+} sdcard_type_t;
+
+#endif /* _SD_DISKIO_H_ */

lib/SD/src/sd_diskio.cpp

@@ -0,0 +1,949 @@
+// roro9stack's copy of the SD-over-SPI driver from Arduino-ESP32 3.3.12 (libraries/SD/src/
+// sd_diskio.cpp), linked instead of the framework's: defining every function the SD class needs
+// keeps the library's file out of the link. Changes are marked "roro:". Why (issue #21): the
+// original gives up on a write without saying why, and never resends a block the card rejects.
+//
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Disable the automatic pin remapping of the API calls in this file
+#define ARDUINO_CORE_BUILD
+
+#include "Arduino.h"
+#include "sd_diskio.h"
+#include "esp_system.h"
+#include "esp32-hal-periman.h"
+
+extern "C" {
+#include "ff.h"
+#include "diskio.h"
+#if ESP_IDF_VERSION_MAJOR > 3
+#include "diskio_impl.h"
+#endif
+//#include "esp_vfs.h"
+#include "esp_vfs_fat.h"
+
+char CRC7(const char *data, int length);
+unsigned short CRC16(const char *data, int length);
+}
+
+// roro: why the last write failed.
+#include "sd_fault.h"
+static roro::SdFault s_fault;
+static bool sdFault(roro::SdFault::Step step, uint8_t token = 0, uint32_t resp = 0) {
+  s_fault.step = step;
+  s_fault.token = token;
+  s_fault.resp = resp;
+  s_fault.count++;
+  return false;
+}
+namespace roro {
+SdFault sdLastFault() { return s_fault; }
+}  // namespace roro
+
+typedef enum {
+  GO_IDLE_STATE = 0,
+  SEND_OP_COND = 1,
+  SEND_CID = 2,
+  SEND_RELATIVE_ADDR = 3,
+  SEND_SWITCH_FUNC = 6,
+  SEND_IF_COND = 8,
+  SEND_CSD = 9,
+  STOP_TRANSMISSION = 12,
+  SEND_STATUS = 13,
+  SET_BLOCKLEN = 16,
+  READ_BLOCK_SINGLE = 17,
+  READ_BLOCK_MULTIPLE = 18,
+  SEND_NUM_WR_BLOCKS = 22,
+  SET_WR_BLK_ERASE_COUNT = 23,
+  WRITE_BLOCK_SINGLE = 24,
+  WRITE_BLOCK_MULTIPLE = 25,
+  APP_OP_COND = 41,
+  APP_CLR_CARD_DETECT = 42,
+  APP_CMD = 55,
+  READ_OCR = 58,
+  CRC_ON_OFF = 59
+} ardu_sdcard_command_t;
+
+// Align with ESP-IDF sdmmc SPI init (ACMD41 timeout must be >1s per SD spec)
+static constexpr uint32_t sd_go_idle_delay_ms = 20;
+static constexpr uint32_t sd_op_cond_timeout_ms = 3000;
+
+typedef struct {
+  uint8_t ssPin;
+  SPIClass *spi;
+  int frequency;
+  char *base_path;
+  sdcard_type_t type;
+  unsigned long sectors;
+  bool supports_crc;
+  int status;
+} ardu_sdcard_t;
+
+static ardu_sdcard_t *s_cards[FF_VOLUMES] = {NULL};
+
+#if ARDUHAL_LOG_LEVEL >= ARDUHAL_LOG_LEVEL_ERROR
+const char *fferr2str[] = {
+  "(0) Succeeded",
+  "(1) A hard error occurred in the low level disk I/O layer",
+  "(2) Assertion failed",
+  "(3) The physical drive cannot work",
+  "(4) Could not find the file",
+  "(5) Could not find the path",
+  "(6) The path name format is invalid",
+  "(7) Access denied due to prohibited access or directory full",
+  "(8) Access denied due to prohibited access",
+  "(9) The file/directory object is invalid",
+  "(10) The physical drive is write protected",
+  "(11) The logical drive number is invalid",
+  "(12) The volume has no work area",
+  "(13) There is no valid FAT volume",
+  "(14) The f_mkfs() aborted due to any problem",
+  "(15) Could not get a grant to access the volume within defined period",
+  "(16) The operation is rejected according to the file sharing policy",
+  "(17) LFN working buffer could not be allocated",
+  "(18) Number of open files > FF_FS_LOCK",
+  "(19) Given parameter is invalid"
+};
+#endif
+
+/*
+ * SD SPI
+ * */
+
+bool sdWait(uint8_t pdrv, int timeout) {
+  char resp;
+  uint32_t start = millis();
+
+  do {
+    resp = s_cards[pdrv]->spi->transfer(0xFF);
+  } while (resp == 0x00 && (millis() - start) < (unsigned int)timeout);
+
+  if (!resp) {
+    log_w("Wait Failed");
+  }
+  return (resp > 0x00);
+}
+
+void sdStop(uint8_t pdrv) {
+  s_cards[pdrv]->spi->write(0xFD);
+}
+
+void sdDeselectCard(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  digitalWrite(card->ssPin, HIGH);
+}
+
+bool sdSelectCard(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  digitalWrite(card->ssPin, LOW);
+  // roro: one dummy byte before asking whether the card is ready, as ChaN's reference driver does.
+  // A card that has just been given a write takes about a byte of clock to signal busy; without
+  // this, that first byte reads 0xFF, "ready", and the next command (the status check after a
+  // write) goes out while the card is still programming and comes back as garbage (#21).
+  card->spi->transfer(0xFF);
+  bool s = sdWait(pdrv, 500);
+  if (!s) {
+    log_e("Select Failed");
+    digitalWrite(card->ssPin, HIGH);
+    return false;
+  }
+  return true;
+}
+
+char sdCommand(uint8_t pdrv, char cmd, unsigned int arg, unsigned int *resp) {
+  char token;
+  ardu_sdcard_t *card = s_cards[pdrv];
+
+  for (int f = 0; f < 3; f++) {
+    if (cmd == SEND_NUM_WR_BLOCKS || cmd == SET_WR_BLK_ERASE_COUNT || cmd == APP_OP_COND || cmd == APP_CLR_CARD_DETECT) {
+      token = sdCommand(pdrv, APP_CMD, 0, NULL);
+      sdDeselectCard(pdrv);
+      if (token > 1) {
+        break;
+      }
+      if (!sdSelectCard(pdrv)) {
+        token = 0xFF;
+        break;
+      }
+    }
+
+    char cmdPacket[7];
+    cmdPacket[0] = cmd | 0x40;
+    cmdPacket[1] = arg >> 24;
+    cmdPacket[2] = arg >> 16;
+    cmdPacket[3] = arg >> 8;
+    cmdPacket[4] = arg;
+    if (card->supports_crc || cmd == GO_IDLE_STATE || cmd == SEND_IF_COND) {
+      cmdPacket[5] = (CRC7(cmdPacket, 5) << 1) | 0x01;
+    } else {
+      cmdPacket[5] = 0x01;
+    }
+    cmdPacket[6] = 0xFF;
+
+    card->spi->writeBytes((uint8_t *)cmdPacket, (cmd == STOP_TRANSMISSION) ? 7 : 6);
+
+    for (int i = 0; i < 9; i++) {
+      token = card->spi->transfer(0xFF);
+      if (!(token & 0x80)) {
+        break;
+      }
+    }
+
+    if (token == 0xFF) {
+      log_w("no token received");
+      sdDeselectCard(pdrv);
+      delay(100);
+      sdSelectCard(pdrv);
+      continue;
+    } else if (token & 0x08) {
+      log_w("crc error");
+      sdDeselectCard(pdrv);
+      delay(100);
+      sdSelectCard(pdrv);
+      continue;
+    } else if (token > 1) {
+      log_w("token error [%u] 0x%x", cmd, token);
+      break;
+    }
+
+    if (cmd == SEND_STATUS && resp) {
+      *resp = card->spi->transfer(0xFF);
+    } else if ((cmd == SEND_IF_COND || cmd == READ_OCR) && resp) {
+      *resp = card->spi->transfer32(0xFFFFFFFF);
+    }
+
+    break;
+  }
+  if (token == 0xFF) {
+    log_e("Card Failed! cmd: 0x%02x", cmd);
+    card->status = STA_NOINIT;
+  }
+  return token;
+}
+
+bool sdReadBytes(uint8_t pdrv, char *buffer, int length) {
+  char token;
+  unsigned short crc;
+  ardu_sdcard_t *card = s_cards[pdrv];
+
+  uint32_t start = millis();
+  do {
+    token = card->spi->transfer(0xFF);
+  } while (token == 0xFF && (millis() - start) < 500);
+
+  if (token != 0xFE) {
+    return false;
+  }
+
+  card->spi->transferBytes(NULL, (uint8_t *)buffer, length);
+  crc = card->spi->transfer16(0xFFFF);
+  return (!card->supports_crc || crc == CRC16(buffer, length));
+}
+
+char sdWriteBytes(uint8_t pdrv, const char *buffer, char token) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  unsigned short crc = (card->supports_crc) ? CRC16(buffer, 512) : 0xFFFF;
+  if (!sdWait(pdrv, 500)) {
+    return 0;
+  }
+
+  card->spi->write(token);
+  card->spi->writeBytes((uint8_t *)buffer, 512);
+  card->spi->write16(crc);
+  return (card->spi->transfer(0xFF) & 0x1F);
+}
+
+/*
+ * SPI SDCARD Communication
+ * */
+
+char sdTransaction(uint8_t pdrv, char cmd, unsigned int arg, unsigned int *resp) {
+  if (!sdSelectCard(pdrv)) {
+    return 0xFF;
+  }
+  char token = sdCommand(pdrv, cmd, arg, resp);
+  sdDeselectCard(pdrv);
+  return token;
+}
+
+bool sdReadSector(uint8_t pdrv, char *buffer, unsigned long long sector) {
+  for (int f = 0; f < 3; f++) {
+    if (!sdSelectCard(pdrv)) {
+      return false;
+    }
+    if (!sdCommand(pdrv, READ_BLOCK_SINGLE, (s_cards[pdrv]->type == CARD_SDHC) ? sector : sector << 9, NULL)) {
+      bool success = sdReadBytes(pdrv, buffer, 512);
+      sdDeselectCard(pdrv);
+      if (success) {
+        return true;
+      }
+    } else {
+      break;
+    }
+  }
+  sdDeselectCard(pdrv);
+  return false;
+}
+
+bool sdReadSectors(uint8_t pdrv, char *buffer, unsigned long long sector, int count) {
+  for (int f = 0; f < 3;) {
+    if (!sdSelectCard(pdrv)) {
+      return false;
+    }
+
+    if (!sdCommand(pdrv, READ_BLOCK_MULTIPLE, (s_cards[pdrv]->type == CARD_SDHC) ? sector : sector << 9, NULL)) {
+      do {
+        if (!sdReadBytes(pdrv, buffer, 512)) {
+          f++;
+          break;
+        }
+
+        sector++;
+        buffer += 512;
+        f = 0;
+      } while (--count);
+
+      if (sdCommand(pdrv, STOP_TRANSMISSION, 0, NULL)) {
+        log_e("command failed");
+        break;
+      }
+
+      sdDeselectCard(pdrv);
+      if (count == 0) {
+        return true;
+      }
+    } else {
+      break;
+    }
+  }
+  sdDeselectCard(pdrv);
+  return false;
+}
+
+bool sdWriteSector(uint8_t pdrv, const char *buffer, unsigned long long sector) {
+  using roro::SdFault;
+  for (int f = 0; f < 3; f++) {
+    if (!sdSelectCard(pdrv)) {
+      return sdFault(SdFault::Select);  // roro: say why
+    }
+    if (!sdCommand(pdrv, WRITE_BLOCK_SINGLE, (s_cards[pdrv]->type == CARD_SDHC) ? sector : sector << 9, NULL)) {
+      char token = sdWriteBytes(pdrv, buffer, 0xFE);
+      sdDeselectCard(pdrv);
+
+      if (token == 0x0A) {
+        continue;
+      } else if (token == 0x0C) {
+        return sdFault(SdFault::DataToken, token);
+      }
+
+      unsigned int resp;
+      char status = sdTransaction(pdrv, SEND_STATUS, 0, &resp);
+      if (status || resp) {
+        return token != 0x05 ? sdFault(SdFault::DataToken, token, resp) : sdFault(SdFault::Status, status, resp);
+      }
+      return true;
+    } else {
+      break;
+    }
+  }
+  sdDeselectCard(pdrv);
+  return sdFault(SdFault::Command);
+}
+
+bool sdWriteSectors(uint8_t pdrv, const char *buffer, unsigned long long sector, int count) {
+  using roro::SdFault;
+  char token;
+  const char *currentBuffer = buffer;
+  unsigned long long currentSector = sector;
+  int currentCount = count;
+  ardu_sdcard_t *card = s_cards[pdrv];
+  SdFault::Step why = SdFault::Command;  // roro: what stopped it, for the last return
+  uint8_t whyToken = 0;
+
+  for (int f = 0; f < 3;) {
+    if (card->type != CARD_MMC) {
+      char refused = sdTransaction(pdrv, SET_WR_BLK_ERASE_COUNT, currentCount, NULL);
+      if (refused) {
+        return sdFault(SdFault::EraseCount, refused);
+      }
+    }
+
+    if (!sdSelectCard(pdrv)) {
+      return sdFault(SdFault::Select);
+    }
+
+    if (!sdCommand(pdrv, WRITE_BLOCK_MULTIPLE, (card->type == CARD_SDHC) ? currentSector : currentSector << 9, NULL)) {
+      do {
+        token = sdWriteBytes(pdrv, currentBuffer, 0xFC);
+        if (token != 0x05) {
+          f++;
+          break;
+        }
+        currentBuffer += 512;
+        f = 0;
+      } while (--currentCount);
+
+      if (!sdWait(pdrv, 500)) {
+        why = SdFault::BusyAfter;
+        break;
+      }
+
+      if (currentCount == 0) {
+        sdStop(pdrv);
+        card->spi->transfer(0xFF);  // roro: the byte the card takes to go busy after Stop Tran (#21)
+        sdDeselectCard(pdrv);
+
+        unsigned int resp;
+        char status = sdTransaction(pdrv, SEND_STATUS, 0, &resp);
+        if (status || resp) {
+          return sdFault(SdFault::Status, status, resp);
+        }
+        return true;
+      } else {
+        if (sdCommand(pdrv, STOP_TRANSMISSION, 0, NULL)) {
+          why = SdFault::StopCommand;
+          whyToken = token;
+          break;
+        }
+
+        if (token == 0x0A) {
+          sdDeselectCard(pdrv);
+          unsigned int writtenBlocks = 0;
+          if (card->type != CARD_MMC && sdSelectCard(pdrv)) {
+            if (!sdCommand(pdrv, SEND_NUM_WR_BLOCKS, 0, NULL)) {
+              char acmdData[4];
+              if (sdReadBytes(pdrv, acmdData, 4)) {
+                writtenBlocks = acmdData[0] << 24;
+                writtenBlocks |= acmdData[1] << 16;
+                writtenBlocks |= acmdData[2] << 8;
+                writtenBlocks |= acmdData[3];
+              }
+            }
+            sdDeselectCard(pdrv);
+          }
+          currentBuffer = buffer + (writtenBlocks << 9);
+          currentSector = sector + writtenBlocks;
+          currentCount = count - writtenBlocks;
+          continue;
+        } else {
+          why = SdFault::DataToken;
+          whyToken = token;
+          break;
+        }
+      }
+    } else {
+      break;
+    }
+  }
+  sdDeselectCard(pdrv);
+  return sdFault(why, whyToken);
+}
+
+unsigned long sdGetSectorsCount(uint8_t pdrv) {
+  for (int f = 0; f < 3; f++) {
+    if (!sdSelectCard(pdrv)) {
+      return 0;
+    }
+
+    if (!sdCommand(pdrv, SEND_CSD, 0, NULL)) {
+      char csd[16];
+      bool success = sdReadBytes(pdrv, csd, 16);
+      sdDeselectCard(pdrv);
+      if (success) {
+        if ((csd[0] >> 6) == 0x01) {
+          unsigned long size = (((unsigned long)(csd[7] & 0x3F) << 16) | ((unsigned long)csd[8] << 8) | csd[9]) + 1;
+          return size << 10;
+        }
+        unsigned long size = (((unsigned long)(csd[6] & 0x03) << 10) | ((unsigned long)csd[7] << 2) | ((csd[8] & 0xC0) >> 6)) + 1;
+        size <<= ((((csd[9] & 0x03) << 1) | ((csd[10] & 0x80) >> 7)) + 2);
+        size <<= (csd[5] & 0x0F);
+        return size >> 9;
+      }
+    } else {
+      break;
+    }
+  }
+
+  sdDeselectCard(pdrv);
+  return 0;
+}
+
+namespace {
+
+struct AcquireSPI {
+  ardu_sdcard_t *card;
+  explicit AcquireSPI(ardu_sdcard_t *card) : card(card) {
+    card->spi->beginTransaction(SPISettings(card->frequency, MSBFIRST, SPI_MODE0));
+  }
+  AcquireSPI(ardu_sdcard_t *card, int frequency) : card(card) {
+    card->spi->beginTransaction(SPISettings(frequency, MSBFIRST, SPI_MODE0));
+  }
+  ~AcquireSPI() {
+    card->spi->endTransaction();
+  }
+
+private:
+  AcquireSPI(AcquireSPI const &);
+  AcquireSPI &operator=(AcquireSPI const &);
+};
+
+}  // namespace
+
+/*
+ * FATFS API
+ * */
+
+/**
+ * @brief Initialize an SD card for use with FatFs
+ *
+ * This function implements the complete SD card initialization sequence according to
+ * the SD card specification. It performs card detection, type identification,
+ * and configuration for SPI mode operation.
+ *
+ * The initialization sequence follows the SD card protocol (SPI mode, aligned with IDF):
+ * 1. Power-up sequence with 74+ clock cycles
+ * 2. Two GO_IDLE_STATE attempts to enter SPI mode
+ * 3. CRC_ON_OFF to enable CRC checking (with retry)
+ * 4. SEND_IF_COND to identify SDHC/SDXC cards
+ * 5. APP_OP_COND / SEND_OP_COND (SPI args; timeout >1s)
+ * 6. Card type detection (SD/SDHC/MMC)
+ * 7. Final configuration and sector count retrieval
+ *
+ * @param pdrv Physical drive number (0-9)
+ * @return DSTATUS Status of the initialization (0 = success, STA_NOINIT = failed)
+ */
+DSTATUS ff_sd_initialize(uint8_t pdrv) {
+  char token;
+  unsigned int resp;
+  unsigned int start;
+
+  // Get the card structure for the given drive number
+  ardu_sdcard_t *card = s_cards[pdrv];
+
+  // If the card is already initialized, return its current status
+  if (!(card->status & STA_NOINIT)) {
+    return card->status;
+  }
+
+  // Lock the SPI bus and set it to a low frequency (400kHz) for initialization
+  // Low frequency is required during initialization for reliable communication
+  AcquireSPI card_locked(card, 400000);
+
+  // Step 1: Power-up sequence - Send at least 74 clock cycles with CS high and MOSI high
+  // This is required by the SD card specification to ensure proper card state reset
+  // We send 20 bytes (160 clock cycles) to exceed the minimum requirement
+  digitalWrite(card->ssPin, HIGH);
+  for (uint8_t i = 0; i < 20; i++) {
+    card->spi->transfer(0XFF);
+  }
+
+  // Step 2: Perform two GO_IDLE_STATE (CMD0) attempts in SPI mode.
+  // Per SD Simplified Spec (figure 4-1) / IDF: some cards enter SD mode on the
+  // first attempt, so the first response may fail; the second must succeed.
+  // (sdCommand may also retry internally on no-token/CRC errors.)
+  // Fix mount issue - sdWait fail ignored before each CMD0 attempt
+  digitalWrite(card->ssPin, LOW);
+  if (!sdWait(pdrv, 500)) {
+    log_w("sdWait fail ignored, card initialize continues");
+  }
+  (void)sdCommand(pdrv, GO_IDLE_STATE, 0, NULL);
+  sdDeselectCard(pdrv);
+  delay(sd_go_idle_delay_ms);
+
+  digitalWrite(card->ssPin, LOW);
+  if (!sdWait(pdrv, 500)) {
+    log_w("sdWait fail ignored, card initialize continues");
+  }
+  if (sdCommand(pdrv, GO_IDLE_STATE, 0, NULL) != 1) {
+    sdDeselectCard(pdrv);
+    log_w("GO_IDLE_STATE failed");
+    goto unknown_card;
+  }
+  sdDeselectCard(pdrv);
+  delay(sd_go_idle_delay_ms);
+
+  // Step 3: Configure CRC checking
+  // Enable CRC for data transfers in SPI mode (required for reliable communication).
+  // Some cards reject the first CRC_ON_OFF; retry once (same as IDF).
+  token = sdTransaction(pdrv, CRC_ON_OFF, 1, NULL);
+  if (token != 1 && token != 0x5) {
+    delay(10);
+    token = sdTransaction(pdrv, CRC_ON_OFF, 1, NULL);
+  }
+  if (token == 0x5) {
+    // Old card that doesn't support CRC - disable CRC checking
+    card->supports_crc = false;
+  } else if (token != 1) {
+    log_w("CRC_ON_OFF failed: %u", token);
+    goto unknown_card;
+  }
+
+  // Step 4: Card type detection and initialization
+  // Try to identify SDHC/SDXC cards using SEND_IF_COND command
+  if (sdTransaction(pdrv, SEND_IF_COND, 0x1AA, &resp) == 1) {
+    // Card responded to SEND_IF_COND - likely SDHC/SDXC
+    if ((resp & 0xFFF) != 0x1AA) {
+      log_w("SEND_IF_COND failed: %03" PRIX32, (uint32_t)(resp & 0xFFF));
+      goto unknown_card;
+    }
+
+    // Read Operating Conditions Register to check card capabilities
+    if (sdTransaction(pdrv, READ_OCR, 0, &resp) != 1 || !(resp & (1 << 20))) {
+      log_w("READ_OCR failed: %X", resp);
+      goto unknown_card;
+    }
+
+    // Send APP_OP_COND to set operating conditions for SDHC/SDXC.
+    // In SPI mode only HCS (bit 30) is valid; voltage bits must be 0 (same as IDF).
+    // Timeout must be >1s per SD spec (IDF uses ~3s).
+    start = millis();
+    do {
+      token = sdTransaction(pdrv, APP_OP_COND, 0x40000000, NULL);
+    } while (token == 1 && (millis() - start) < sd_op_cond_timeout_ms);
+
+    if (token) {
+      log_w("APP_OP_COND failed: %u", token);
+      goto unknown_card;
+    }
+
+    // Determine if it's SDHC (high capacity) or regular SD
+    if (!sdTransaction(pdrv, READ_OCR, 0, &resp)) {
+      if (resp & (1 << 30)) {
+        card->type = CARD_SDHC;  // High capacity card (SDHC/SDXC)
+      } else {
+        card->type = CARD_SD;  // Standard capacity card
+      }
+    } else {
+      log_w("READ_OCR failed: %X", resp);
+      goto unknown_card;
+    }
+  } else {
+    // Card didn't respond to SEND_IF_COND - try SD or MMC initialization
+    if (sdTransaction(pdrv, READ_OCR, 0, &resp) != 1 || !(resp & (1 << 20))) {
+      log_w("READ_OCR failed: %X", resp);
+      goto unknown_card;
+    }
+
+    // Try SD card initialization first (SPI mode: ACMD41 arg must be 0)
+    start = millis();
+    do {
+      token = sdTransaction(pdrv, APP_OP_COND, 0, NULL);
+    } while (token == 0x01 && (millis() - start) < sd_op_cond_timeout_ms);
+
+    if (!token) {
+      card->type = CARD_SD;  // Standard SD card
+    } else {
+      // Try MMC card initialization (SPI mode: CMD1 arg must be 0)
+      start = millis();
+      do {
+        token = sdTransaction(pdrv, SEND_OP_COND, 0, NULL);
+      } while (token != 0x00 && (millis() - start) < sd_op_cond_timeout_ms);
+
+      if (token == 0x00) {
+        card->type = CARD_MMC;  // MMC card
+      } else {
+        log_w("SEND_OP_COND failed: %u", token);
+        goto unknown_card;
+      }
+    }
+  }
+
+  // Step 5: Clear card detection for SD cards (not needed for MMC)
+  if (card->type != CARD_MMC) {
+    if (sdTransaction(pdrv, APP_CLR_CARD_DETECT, 0, NULL)) {
+      log_w("APP_CLR_CARD_DETECT failed");
+      goto unknown_card;
+    }
+  }
+
+  // Step 6: Set block length for non-SDHC cards
+  // SDHC cards have fixed 512-byte blocks, others need explicit block length setting
+  if (card->type != CARD_SDHC) {
+    if (sdTransaction(pdrv, SET_BLOCKLEN, 512, NULL) != 0x00) {
+      log_w("SET_BLOCKLEN failed");
+      goto unknown_card;
+    }
+  }
+
+  // Step 7: Get card capacity and finalize initialization
+  card->sectors = sdGetSectorsCount(pdrv);
+
+  // Limit frequency to 25MHz for compatibility (SD spec maximum for non-UHS cards)
+  if (card->frequency > 25000000) {
+    card->frequency = 25000000;
+  }
+
+  // Mark card as initialized
+  card->status &= ~STA_NOINIT;
+  return card->status;
+
+unknown_card:
+  // Mark card as unknown type if initialization failed
+  card->type = CARD_UNKNOWN;
+  return card->status;
+}
+
+DSTATUS ff_sd_status(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  AcquireSPI lock(card);
+
+  if (sdTransaction(pdrv, SEND_STATUS, 0, NULL)) {
+    log_e("Check status failed");
+    return STA_NOINIT;
+  }
+  return s_cards[pdrv]->status;
+}
+
+DRESULT ff_sd_read(uint8_t pdrv, uint8_t *buffer, DWORD sector, UINT count) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (card->status & STA_NOINIT) {
+    return RES_NOTRDY;
+  }
+  DRESULT res = RES_OK;
+
+  AcquireSPI lock(card);
+
+  if (count > 1) {
+    res = sdReadSectors(pdrv, (char *)buffer, sector, count) ? RES_OK : RES_ERROR;
+  } else {
+    res = sdReadSector(pdrv, (char *)buffer, sector) ? RES_OK : RES_ERROR;
+  }
+  return res;
+}
+
+DRESULT ff_sd_write(uint8_t pdrv, const uint8_t *buffer, DWORD sector, UINT count) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (card->status & STA_NOINIT) {
+    return RES_NOTRDY;
+  }
+
+  if (card->status & STA_PROTECT) {
+    return RES_WRPRT;
+  }
+  DRESULT res = RES_OK;
+
+  AcquireSPI lock(card);
+
+  if (count > 1) {
+    res = sdWriteSectors(pdrv, (const char *)buffer, sector, count) ? RES_OK : RES_ERROR;
+  } else {
+    res = sdWriteSector(pdrv, (const char *)buffer, sector) ? RES_OK : RES_ERROR;
+  }
+  return res;
+}
+
+DRESULT ff_sd_ioctl(uint8_t pdrv, uint8_t cmd, void *buff) {
+  switch (cmd) {
+    case CTRL_SYNC:
+    {
+      AcquireSPI lock(s_cards[pdrv]);
+      if (sdSelectCard(pdrv)) {
+        sdDeselectCard(pdrv);
+        return RES_OK;
+      }
+    }
+      return RES_ERROR;
+    case GET_SECTOR_COUNT: *((unsigned long *)buff) = s_cards[pdrv]->sectors; return RES_OK;
+    case GET_SECTOR_SIZE:  *((WORD *)buff) = 512; return RES_OK;
+    case GET_BLOCK_SIZE:   *((uint32_t *)buff) = 1; return RES_OK;
+  }
+  return RES_PARERR;
+}
+
+bool sd_read_raw(uint8_t pdrv, uint8_t *buffer, DWORD sector) {
+  return ff_sd_read(pdrv, buffer, sector, 1) == ESP_OK;
+}
+
+bool sd_write_raw(uint8_t pdrv, uint8_t *buffer, DWORD sector) {
+  return ff_sd_write(pdrv, buffer, sector, 1) == ESP_OK;
+}
+
+/*
+ * Public methods
+ * */
+
+uint8_t sdcard_uninit(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (pdrv >= FF_VOLUMES || card == NULL) {
+    return 1;
+  }
+  {
+    AcquireSPI lock(card);
+    sdTransaction(pdrv, GO_IDLE_STATE, 0, NULL);
+  }  // lock is destructed here
+  ff_diskio_register(pdrv, NULL);
+  s_cards[pdrv] = NULL;
+  esp_err_t err = ESP_OK;
+  if (card->base_path) {
+    err = esp_vfs_fat_unregister_path(card->base_path);
+    free(card->base_path);
+  }
+  free(card);
+  return err;
+}
+
+uint8_t sdcard_init(uint8_t cs, SPIClass *spi, int hz) {
+
+  uint8_t pdrv = 0xFF;
+  if (ff_diskio_get_drive(&pdrv) != ESP_OK || pdrv == 0xFF) {
+    return pdrv;
+  }
+
+  ardu_sdcard_t *card = (ardu_sdcard_t *)malloc(sizeof(ardu_sdcard_t));
+  if (!card) {
+    return 0xFF;
+  }
+
+  card->base_path = NULL;
+  card->frequency = hz;
+  card->spi = spi;
+  card->ssPin = digitalPinToGPIONumber(cs);
+
+  card->supports_crc = true;
+  card->type = CARD_NONE;
+  card->status = STA_NOINIT;
+
+  pinMode(card->ssPin, OUTPUT);
+  digitalWrite(card->ssPin, HIGH);
+  perimanSetPinBusExtraType(card->ssPin, "SD_SS");
+
+  s_cards[pdrv] = card;
+
+  static const ff_diskio_impl_t sd_impl = {
+    .init = &ff_sd_initialize, .status = &ff_sd_status, .read = &ff_sd_read, .write = &ff_sd_write, .ioctl = &ff_sd_ioctl
+  };
+  ff_diskio_register(pdrv, &sd_impl);
+
+  return pdrv;
+}
+
+uint8_t sdcard_unmount(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (pdrv >= FF_VOLUMES || card == NULL) {
+    return 1;
+  }
+  card->status |= STA_NOINIT;
+  card->type = CARD_NONE;
+
+  char drv[3] = {(char)('0' + pdrv), ':', 0};
+  f_mount(NULL, drv, 0);
+  return 0;
+}
+
+bool sdcard_mount(uint8_t pdrv, const char *path, uint8_t max_files, bool format_if_empty) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (pdrv >= FF_VOLUMES || card == NULL) {
+    return false;
+  }
+
+  if (card->base_path) {
+    free(card->base_path);
+  }
+  card->base_path = strdup(path);
+
+  FATFS *fs;
+  char drv[3] = {(char)('0' + pdrv), ':', 0};
+
+#if ESP_IDF_VERSION < ESP_IDF_VERSION_VAL(6, 0, 0)
+  esp_err_t err = esp_vfs_fat_register(path, drv, max_files, &fs);
+#else
+  esp_vfs_fat_conf_t conf = {.base_path = path, .fat_drive = drv, .max_files = max_files};
+  esp_err_t err = esp_vfs_fat_register(&conf, &fs);
+#endif
+
+  if (err == ESP_ERR_INVALID_STATE) {
+    log_e("esp_vfs_fat_register failed 0x(%x): SD is registered.", err);
+    return false;
+  } else if (err != ESP_OK) {
+    log_e("esp_vfs_fat_register failed 0x(%x)", err);
+    return false;
+  }
+
+  FRESULT res = f_mount(fs, drv, 1);
+  if (res != FR_OK) {
+    log_e("f_mount failed: %s", fferr2str[res]);
+    if (res == 13 && format_if_empty) {
+      BYTE *work = (BYTE *)malloc(sizeof(BYTE) * FF_MAX_SS);
+      if (!work) {
+        log_e("alloc for f_mkfs failed");
+        return false;
+      }
+      //FRESULT f_mkfs (const TCHAR* path, const MKFS_PARM* opt, void* work, UINT len);
+      const MKFS_PARM opt = {(BYTE)FM_ANY, 0, 0, 0, 0};
+      res = f_mkfs(drv, &opt, work, sizeof(BYTE) * FF_MAX_SS);
+      free(work);
+      if (res != FR_OK) {
+        log_e("f_mkfs failed: %s", fferr2str[res]);
+        esp_vfs_fat_unregister_path(path);
+        return false;
+      }
+      res = f_mount(fs, drv, 1);
+      if (res != FR_OK) {
+        log_e("f_mount failed: %s", fferr2str[res]);
+        esp_vfs_fat_unregister_path(path);
+        return false;
+      }
+    } else {
+      esp_vfs_fat_unregister_path(path);
+      return false;
+    }
+  }
+  AcquireSPI lock(card);
+  card->sectors = sdGetSectorsCount(pdrv);
+  return true;
+}
+
+uint32_t sdcard_num_sectors(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (pdrv >= FF_VOLUMES || card == NULL) {
+    return 0;
+  }
+  return card->sectors;
+}
+
+uint32_t sdcard_sector_size(uint8_t pdrv) {
+  if (pdrv >= FF_VOLUMES || s_cards[pdrv] == NULL) {
+    return 0;
+  }
+  return 512;
+}
+
+// roro: the card's CID. CMD10 in SPI mode (the enum's SEND_CID, 2, is the SD-mode command).
+namespace roro {
+bool sdReadCid(uint8_t cid[16]) {
+  for (uint8_t pdrv = 0; pdrv < FF_VOLUMES; ++pdrv) {
+    ardu_sdcard_t *card = s_cards[pdrv];
+    if (!card) {
+      continue;
+    }
+    AcquireSPI lock(card);
+    if (!sdSelectCard(pdrv)) {
+      return false;
+    }
+    bool ok = !sdCommand(pdrv, 10, 0, NULL) && sdReadBytes(pdrv, (char *)cid, 16);
+    sdDeselectCard(pdrv);
+    return ok;
+  }
+  return false;
+}
+}  // namespace roro
+
+sdcard_type_t sdcard_type(uint8_t pdrv) {
+  ardu_sdcard_t *card = s_cards[pdrv];
+  if (pdrv >= FF_VOLUMES || card == NULL) {
+    return CARD_NONE;
+  }
+  return card->type;
+}

lib/SD/src/sd_diskio.h

@@ -0,0 +1,34 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#ifndef _SD_DISKIO_H_
+#define _SD_DISKIO_H_
+
+#include "Arduino.h"
+#include "SPI.h"
+#include "sd_defines.h"
+// #include "diskio.h"
+
+uint8_t sdcard_init(uint8_t cs, SPIClass *spi, int hz);
+uint8_t sdcard_uninit(uint8_t pdrv);
+
+bool sdcard_mount(uint8_t pdrv, const char *path, uint8_t max_files, bool format_if_empty);
+uint8_t sdcard_unmount(uint8_t pdrv);
+
+sdcard_type_t sdcard_type(uint8_t pdrv);
+uint32_t sdcard_num_sectors(uint8_t pdrv);
+uint32_t sdcard_sector_size(uint8_t pdrv);
+bool sd_read_raw(uint8_t pdrv, uint8_t *buffer, uint32_t sector);
+bool sd_write_raw(uint8_t pdrv, uint8_t *buffer, uint32_t sector);
+
+#endif /* _SD_DISKIO_H_ */

lib/SD/src/sd_diskio_crc.c

@@ -0,0 +1,61 @@
+/* SD/MMC File System Library
+ * Copyright (c) 2014 Neil Thiessen
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const char m_CRC7Table[] = {0x00, 0x09, 0x12, 0x1B, 0x24, 0x2D, 0x36, 0x3F, 0x48, 0x41, 0x5A, 0x53, 0x6C, 0x65, 0x7E, 0x77, 0x19, 0x10, 0x0B, 0x02, 0x3D, 0x34,
+                            0x2F, 0x26, 0x51, 0x58, 0x43, 0x4A, 0x75, 0x7C, 0x67, 0x6E, 0x32, 0x3B, 0x20, 0x29, 0x16, 0x1F, 0x04, 0x0D, 0x7A, 0x73, 0x68, 0x61,
+                            0x5E, 0x57, 0x4C, 0x45, 0x2B, 0x22, 0x39, 0x30, 0x0F, 0x06, 0x1D, 0x14, 0x63, 0x6A, 0x71, 0x78, 0x47, 0x4E, 0x55, 0x5C, 0x64, 0x6D,
+                            0x76, 0x7F, 0x40, 0x49, 0x52, 0x5B, 0x2C, 0x25, 0x3E, 0x37, 0x08, 0x01, 0x1A, 0x13, 0x7D, 0x74, 0x6F, 0x66, 0x59, 0x50, 0x4B, 0x42,
+                            0x35, 0x3C, 0x27, 0x2E, 0x11, 0x18, 0x03, 0x0A, 0x56, 0x5F, 0x44, 0x4D, 0x72, 0x7B, 0x60, 0x69, 0x1E, 0x17, 0x0C, 0x05, 0x3A, 0x33,
+                            0x28, 0x21, 0x4F, 0x46, 0x5D, 0x54, 0x6B, 0x62, 0x79, 0x70, 0x07, 0x0E, 0x15, 0x1C, 0x23, 0x2A, 0x31, 0x38, 0x41, 0x48, 0x53, 0x5A,
+                            0x65, 0x6C, 0x77, 0x7E, 0x09, 0x00, 0x1B, 0x12, 0x2D, 0x24, 0x3F, 0x36, 0x58, 0x51, 0x4A, 0x43, 0x7C, 0x75, 0x6E, 0x67, 0x10, 0x19,
+                            0x02, 0x0B, 0x34, 0x3D, 0x26, 0x2F, 0x73, 0x7A, 0x61, 0x68, 0x57, 0x5E, 0x45, 0x4C, 0x3B, 0x32, 0x29, 0x20, 0x1F, 0x16, 0x0D, 0x04,
+                            0x6A, 0x63, 0x78, 0x71, 0x4E, 0x47, 0x5C, 0x55, 0x22, 0x2B, 0x30, 0x39, 0x06, 0x0F, 0x14, 0x1D, 0x25, 0x2C, 0x37, 0x3E, 0x01, 0x08,
+                            0x13, 0x1A, 0x6D, 0x64, 0x7F, 0x76, 0x49, 0x40, 0x5B, 0x52, 0x3C, 0x35, 0x2E, 0x27, 0x18, 0x11, 0x0A, 0x03, 0x74, 0x7D, 0x66, 0x6F,
+                            0x50, 0x59, 0x42, 0x4B, 0x17, 0x1E, 0x05, 0x0C, 0x33, 0x3A, 0x21, 0x28, 0x5F, 0x56, 0x4D, 0x44, 0x7B, 0x72, 0x69, 0x60, 0x0E, 0x07,
+                            0x1C, 0x15, 0x2A, 0x23, 0x38, 0x31, 0x46, 0x4F, 0x54, 0x5D, 0x62, 0x6B, 0x70, 0x79};
+
+char CRC7(const char *data, int length) {
+  char crc = 0;
+  for (int i = 0; i < length; i++) {
+    crc = m_CRC7Table[(crc << 1) ^ data[i]];
+  }
+  return crc;
+}
+
+const unsigned short m_CRC16Table[256] = {
+  0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7, 0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210, 0x3273,
+  0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6, 0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7,
+  0x44A4, 0x5485, 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D, 0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4, 0xB75B,
+  0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC, 0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823, 0xC9CC, 0xD9ED, 0xE98E, 0xF9AF,
+  0x8948, 0x9969, 0xA90A, 0xB92B, 0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12, 0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B,
+  0xAB1A, 0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41, 0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49, 0x7E97, 0x6EB6,
+  0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70, 0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78, 0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C,
+  0xC12D, 0xF14E, 0xE16F, 0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067, 0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E,
+  0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256, 0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D, 0x34E2, 0x24C3, 0x14A0,
+  0x0481, 0x7466, 0x6447, 0x5424, 0x4405, 0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C, 0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676,
+  0x4615, 0x5634, 0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB, 0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3, 0xCB7D,
+  0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A, 0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92, 0xFD2E, 0xED0F, 0xDD6C, 0xCD4D,
+  0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9, 0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1, 0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9,
+  0x9FF8, 0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
+};
+
+unsigned short CRC16(const char *data, int length) {
+  unsigned short crc = 0;
+  for (int i = 0; i < length; i++) {
+    crc = (crc << 8) ^ m_CRC16Table[((crc >> 8) ^ data[i]) & 0x00FF];
+  }
+  return crc;
+}

lib/SD/src/sd_fault.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <cstdint>
+
+namespace roro {
+
+// Why the SD driver last gave up on a write (see sd_diskio.cpp, issue #21). The framework's driver
+// fails without saying why; ours records it.
+struct SdFault {
+    enum Step : uint8_t {
+        None,
+        EraseCount,   // ACMD23 before a multi-block write was refused
+        Select,       // the card stayed busy for 500 ms
+        Command,      // the write command itself was refused
+        DataToken,    // the card's answer to a data block: 0x0B CRC error, 0x0D write error
+        BusyAfter,    // still busy 500 ms after the last block
+        Status,       // CMD13 after the write reported an error (resp)
+        StopCommand,  // CMD12 after a rejected block was refused
+    };
+    Step step = None;
+    uint8_t token = 0;   // the driver's or the card's answer at that step
+    uint32_t resp = 0;   // CMD13's status bits, for Status
+    uint32_t count = 0;  // failed writes since boot
+    uint32_t retried = 0;  // blocks resent after a CRC error, since boot
+};
+
+SdFault sdLastFault();
+
+// The mounted card's identity register (CID, CMD10): who made it, its name, serial and date.
+// Call it where card access is allowed (the storage task).
+bool sdReadCid(uint8_t cid[16]);
+
+}  // namespace roro

lib/apps_model/src/settings_menu.cpp

@@ -20,10 +20,11 @@ const RowDef kRows[] = {
     {Row::Region, Kind::Choice, "Region"},      {Row::Timezone, Kind::Choice, "Timezone"},
     {Row::Brightness, Kind::Slider, "Brightness"}, {Row::DimTimeout, Kind::Choice, "Dim after"},
     {Row::OffTimeout, Kind::Choice, "Screen off after"}, {Row::Sound, Kind::Toggle, "Sound & LED"},
+    {Row::Gnss, Kind::Toggle, "GNSS"}, {Row::GnssQuiet, Kind::Toggle, "Pause GNSS for LoRa"},
+    {Row::Coordinates, Kind::Toggle, "Coordinates"},
     {Row::ProbeMacs, Kind::Toggle, "Probe MACs"}, {Row::Wifi, Kind::Page, "Wi-Fi"},
-    {Row::Storage, Kind::Page, "Storage"},
-    {Row::Firmware, Kind::Page, "Firmware"},
-    {Row::About, Kind::Page, "About"},
+    {Row::CheckUpdates, Kind::Toggle, "Check for updates"}, {Row::Firmware, Kind::Page, "Firmware"},
+    {Row::DebugConsole, Kind::Page, "Debug Console"}, {Row::About, Kind::Page, "About"},
 };
 
 const int kDimSeconds[] = {10, 15, 30, 60, 120, 300};
@@ -79,8 +80,13 @@ std::string SettingsMenu::value(int i) const {
         case Row::DimTimeout: return formatSeconds(settings_.getInt(Setting::DimTimeoutS));
         case Row::OffTimeout: return formatSeconds(settings_.getInt(Setting::OffTimeoutS));
         case Row::Sound: return settings_.getBool(Setting::Sound) ? "On" : "Off";
+        case Row::Gnss: return settings_.getBool(Setting::GnssEnabled) ? "On" : "Off";
+        case Row::GnssQuiet: return settings_.getBool(Setting::GnssQuietForLora) ? "On" : "Off";
+        case Row::CheckUpdates: return settings_.getBool(Setting::CheckUpdates) ? "Daily" : "Off";
+        case Row::Coordinates: return settings_.getBool(Setting::CoordinatesDms) ? "Deg min sec" : "Decimal";
         case Row::ProbeMacs: return settings_.getBool(Setting::ProbeMacRaw) ? "Raw" : "Pseudonymised";
         case Row::Wifi: return settings_.getBool(Setting::WifiEnabled) ? "On" : "Off";
+        case Row::DebugConsole: return settings_.getBool(Setting::DebugConsole) ? "On" : "Off";
         default: return "";
     }
 }
@@ -122,6 +128,10 @@ std::string SettingsMenu::choose(int i, int c) {
 
 void SettingsMenu::toggle(int i) {
     if (row(i) == Row::Sound) settings_.setBool(Setting::Sound, !settings_.getBool(Setting::Sound));
+    if (row(i) == Row::Gnss) settings_.setBool(Setting::GnssEnabled, !settings_.getBool(Setting::GnssEnabled));
+    if (row(i) == Row::GnssQuiet) settings_.setBool(Setting::GnssQuietForLora, !settings_.getBool(Setting::GnssQuietForLora));
+    if (row(i) == Row::CheckUpdates) settings_.setBool(Setting::CheckUpdates, !settings_.getBool(Setting::CheckUpdates));
+    if (row(i) == Row::Coordinates) settings_.setBool(Setting::CoordinatesDms, !settings_.getBool(Setting::CoordinatesDms));
     if (row(i) == Row::ProbeMacs) settings_.setBool(Setting::ProbeMacRaw, !settings_.getBool(Setting::ProbeMacRaw));
 }
 

lib/apps_model/src/settings_menu.h

@@ -11,7 +11,7 @@ namespace roro {
 // values, choice lists and validation messages. Rendering and navigation live in the App.
 class SettingsMenu {
    public:
-    enum class Row { LongName, ShortName, Region, Timezone, Brightness, DimTimeout, OffTimeout, Sound, ProbeMacs, Wifi, Storage, Firmware, About };
+    enum class Row { LongName, ShortName, Region, Timezone, Brightness, DimTimeout, OffTimeout, Sound, Gnss, GnssQuiet, Coordinates, ProbeMacs, Wifi, CheckUpdates, Firmware, DebugConsole, About };
     enum class Kind { Text, Choice, Toggle, Slider, Page };
 
     explicit SettingsMenu(Settings& settings) : settings_(settings) {}

lib/apps_model/src/shell_log.cpp

@@ -0,0 +1,171 @@
+#include "shell_log.h"
+
+#include <algorithm>
+
+namespace roro {
+
+void ShellLog::push(const std::string& line) {
+    lines_.push_back(line);
+    bytes_ += line.size() + 1;
+    while (bytes_ > kMaxBytes && lines_.size() > 1) {
+        bytes_ -= lines_.front().size() + 1;
+        lines_.pop_front();
+    }
+    revision_++;
+}
+
+void ShellLog::add(const std::string& line) { push(line); }
+
+void ShellLog::feed(const char* data, size_t len) {
+    for (size_t i = 0; i < len; i++) {
+        char c = data[i];
+        if (c == '\r') continue;
+        if (c != '\n') {
+            if (partial_.size() < 512) partial_ += c;  // a line that never ends doesn't take the heap
+            continue;
+        }
+        if (partial_.rfind("status: heap ", 0) != 0) push(partial_);
+        partial_.clear();
+    }
+}
+
+void ShellLog::clear() {
+    lines_.clear();
+    partial_.clear();
+    bytes_ = 0;
+    revision_++;
+}
+
+namespace {
+
+bool isWord(const std::string& w) {
+    if (w.empty()) return false;
+    for (size_t i = 0; i < w.size(); i++) {
+        bool small = w[i] >= 'a' && w[i] <= 'z', capital = w[i] >= 'A' && w[i] <= 'Z';
+        if (!(small || (i == 0 && capital))) return false;
+    }
+    return true;
+}
+
+std::vector<std::string> split(const std::string& text, const std::string& by) {
+    std::vector<std::string> out;
+    size_t at = 0;
+    for (;;) {
+        size_t next = text.find(by, at);
+        out.push_back(text.substr(at, next == std::string::npos ? std::string::npos : next - at));
+        if (next == std::string::npos) return out;
+        at = next + by.size();
+    }
+}
+
+// The words a command can have at `index`, given the `index` words before it: added to `out`.
+void nextWords(const std::string& command, const std::vector<std::string>& before, size_t index, std::vector<std::string>& out) {
+    std::vector<std::string> tokens;
+    for (auto& t : split(command, " "))
+        if (!t.empty()) tokens.push_back(t);
+    for (size_t i = 0; i < tokens.size(); i++) {
+        std::vector<std::string> either = split(tokens[i], "|");  // on|off: either of them
+        bool words = true;
+        for (auto& w : either) words = words && isWord(w);
+        if (!words) return;  // an <argument>, an [option], "...": the command's words end here
+        if (i == index) {
+            for (auto& w : either)
+                if (std::find(out.begin(), out.end(), w) == out.end()) out.push_back(w);
+            return;
+        }
+        if (std::find(either.begin(), either.end(), before[i]) == either.end()) return;  // another command
+    }
+}
+
+}  // namespace
+
+std::string completeWords(const std::string& typed, const char* helpText, std::vector<std::string>& matches) {
+    matches.clear();
+    std::vector<std::string> words = split(typed, " ");
+    for (size_t i = 0; i + 1 < words.size(); i++)
+        if (words[i].empty()) return typed;  // two spaces: not ours to guess
+    const std::string last = words.back();
+    words.pop_back();
+    if (words.empty() && last.empty()) return typed;
+
+    std::vector<std::string> next;
+    for (auto& line : split(helpText ? helpText : "", "\n")) {
+        std::string commands = line.substr(0, line.find("   "));  // the description starts at three spaces
+        for (auto& command : split(commands, " | ")) nextWords(command, words, words.size(), next);
+    }
+    for (auto& w : next)
+        if (w.rfind(last, 0) == 0) matches.push_back(w);
+    if (matches.empty()) return typed;
+
+    std::string common = matches[0];
+    for (auto& m : matches) {
+        size_t n = 0;
+        while (n < common.size() && n < m.size() && common[n] == m[n]) n++;
+        common.resize(n);
+    }
+    std::string head = typed.substr(0, typed.size() - last.size());
+    if (matches.size() == 1) {
+        matches.clear();
+        return head + common + " ";
+    }
+    return head + common;
+}
+
+namespace {
+
+char lower(char c) { return c >= 'A' && c <= 'Z' ? static_cast<char>(c - 'A' + 'a') : c; }
+
+bool startsWithNoCase(const std::string& name, const std::string& prefix) {
+    if (name.size() < prefix.size()) return false;
+    for (size_t i = 0; i < prefix.size(); i++)
+        if (lower(name[i]) != lower(prefix[i])) return false;
+    return true;
+}
+
+bool takesAPath(const std::string& command) {
+    static const char* const kCommands[] = {"ls", "du", "mkdir", "rm", "cp", "mv", "cat", "install"};
+    for (auto c : kCommands)
+        if (command == c) return true;
+    return false;
+}
+
+}  // namespace
+
+bool splitForPath(const std::string& typed, PathToComplete& out) {
+    size_t space = typed.rfind(' ');
+    if (space == std::string::npos) return false;  // still the command's own word
+    std::string word = typed.substr(space + 1);
+    if (!word.empty() && word[0] == '-') return false;  // a switch
+    if (word.empty() || word[0] != '/') {
+        if (!takesAPath(typed.substr(0, typed.find(' ')))) return false;
+        word = "/" + word;
+    }
+    size_t slash = word.rfind('/');
+    out.head = typed.substr(0, space + 1);
+    out.folder = word.substr(0, slash + 1);
+    out.prefix = word.substr(slash + 1);
+    return true;
+}
+
+std::string completePath(const PathToComplete& what, const std::vector<std::string>& names, std::vector<std::string>& matches) {
+    matches.clear();
+    for (auto& n : names)
+        if (startsWithNoCase(n, what.prefix)) matches.push_back(n);
+    if (matches.empty()) return what.head + what.folder + what.prefix;
+    std::string common = matches[0];
+    for (auto& m : matches) {
+        size_t n = 0;
+        while (n < common.size() && n < m.size() && lower(common[n]) == lower(m[n])) n++;
+        common.resize(n);
+    }
+    if (matches.size() == 1) {
+        bool folder = !common.empty() && common.back() == '/';
+        matches.clear();
+        return what.head + what.folder + common + (folder ? "" : " ");
+    }
+    // Several: never shorter than what was typed (cases may differ past the prefix).
+    if (common.size() < what.prefix.size()) common = what.prefix;
+    return what.head + what.folder + common;
+}
+
+}  // namespace roro

lib/apps_model/src/shell_log.h

@@ -0,0 +1,65 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <deque>
+#include <string>
+#include <vector>
+
+namespace roro {
+
+// What the Shell App shows (issue #67): the lines it was given, with the oldest dropped past a size.
+// Which lines it is given is the console's business: by default, only what is printed for the
+// Shell's own commands (Console::Origin).
+class ShellLog {
+   public:
+    static constexpr size_t kMaxBytes = 4096;
+
+    // Bytes as the console printed them: lines may arrive in pieces. The line with the free heap
+    // every ten seconds is never kept: it would push everything else off a ten-line screen.
+    void feed(const char* data, size_t len);
+    // A line the Shell adds itself.
+    void add(const std::string& line);
+
+    const std::deque<std::string>& lines() const { return lines_; }
+    void clear();
+    uint32_t revision() const { return revision_; }  // changes when the lines do
+
+   private:
+    void push(const std::string& line);
+
+    std::deque<std::string> lines_;
+    std::string partial_;
+    size_t bytes_ = 0;
+    uint32_t revision_ = 0;
+};
+
+// Tab on a command (issue #67): every word of it, read from the firmware's `help` text each time it
+// is asked, so nothing is kept in memory for it. A line of that text is commands, three spaces, then
+// what they do; commands are separated by " | ", a word like on|off is either of them, and a command
+// stops being words at its first <argument>, [option] or "...":
+//     lora rx on|off | lora preset <name>   the radio
+// gives "lora rx on", "lora rx off" and "lora preset". An App's name starts with a capital.
+//
+// The line with its last word completed as far as the commands that fit agree; a word completed
+// whole gets a space after it. `matches` gets the candidates when there are several. Unchanged, with
+// no matches, when no command goes on that way: then it may be a path (below).
+std::string completeWords(const std::string& typed, const char* helpText, std::vector<std::string>& matches);
+
+// Tab on a later word: a path on the SD card (issue #67). What is being completed, taken apart:
+// `rm -r /notes/sh` is head "rm -r ", folder "/notes/", prefix "sh". False when the cursor is still
+// on the first word, when the word is a switch (-r), or when it isn't a path and the command doesn't
+// take one. After a file command a path may be started without its slash: `cat no` is /no.
+struct PathToComplete {
+    std::string head, folder, prefix;
+};
+bool splitForPath(const std::string& typed, PathToComplete& out);
+
+// `names` are the folder's entries, a folder's with a slash at its end. The line with the path
+// completed as far as the entries that start with the prefix agree, whatever their case (the card
+// doesn't tell cases apart, so the name's own case is taken). A file completed whole gets a space
+// after it; a folder keeps its slash, to go on from. `matches` gets the candidates when there are
+// several. Unchanged when nothing matches.
+std::string completePath(const PathToComplete& what, const std::vector<std::string>& names, std::vector<std::string>& matches);
+
+}  // namespace roro

lib/core/src/app.h

@@ -2,7 +2,10 @@
 
 #include <cstdint>
 
+#include <vector>
+
 #include "key_event.h"
+#include "key_help.h"
 
 namespace roro {
 
@@ -25,6 +28,12 @@ class App {
     // True while the App is editing text: the arrow keys then type ; . , / and need Fn to move.
     virtual bool textEntryActive() const { return false; }
 
+    // The keys that work right now, for the help panel (Fn+h): the App's own, in the state it's
+    // in. Back, Home and the arrows are added for it. No screen names keys any other way.
+    virtual void help(std::vector<KeyHelp>& out) const { (void)out; }
+    // What the panel is titled with, when the App's name isn't enough ("Notes: editor").
+    virtual const char* helpTitle() const { return nullptr; }
+
     // Called every main-loop pass while in the foreground (e.g. to refresh live values).
     virtual void update(uint32_t nowMs) { (void)nowMs; }
 

lib/core/src/app_keys.h

@@ -0,0 +1,451 @@
+#pragma once
+
+#include <cstddef>
+#include <vector>
+
+#include "key_help.h"
+
+// Every key of every screen, as data (issues #69 and #72). The help panel (Fn+h) shows the table of
+// the state an App is in; site/tools/gen_dev_docs.py reads this file to write the website's key
+// tables, so the two can't drift.
+//
+// The format is read by that script, so keep it: a comment `// id: Title`, then one table,
+//     inline constexpr KeyHelp kName[] = {
+//         {"keys", "what they do"},
+//     };
+// with one row a line and plain string literals. `id` is what a guide page asks for.
+namespace roro::keys {
+
+template <size_t N>
+inline void add(std::vector<KeyHelp>& out, const KeyHelp (&rows)[N]) {
+    out.insert(out.end(), rows, rows + N);
+}
+
+// everywhere: Everywhere
+inline constexpr KeyHelp kEverywhere[] = {
+    {"`", "back"},
+    {"Fn `", "home, the Launcher"},
+    {"; . , /", "arrows (Fn+ while typing)"},
+    {"Fn h  ?", "these keys (? not typing)"},
+};
+
+// dialog: A question
+inline constexpr KeyHelp kDialog[] = {
+    {", /", "the other answer"},
+    {"Enter", "choose it"},
+    {"`", "cancel"},
+};
+
+// text: A text field
+inline constexpr KeyHelp kText[] = {
+    {"Enter", "save"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+    {"opt ' e", "an accent: \xC3\xA9"},
+};
+
+// launcher: The Launcher
+inline constexpr KeyHelp kLauncher[] = {
+    {"; .", "up, down"},
+    {"Enter", "open the App"},
+};
+
+// setup: Setup, a step
+inline constexpr KeyHelp kSetup[] = {
+    {"Enter", "continue"},
+    {"`", "the step before"},
+};
+
+// setup-choice: Setup, a choice
+inline constexpr KeyHelp kSetupChoice[] = {
+    {"; .", "up, down"},
+    {"Enter", "choose it, next step"},
+    {"`", "the step before"},
+};
+
+// setup-text: Setup, a name
+inline constexpr KeyHelp kSetupText[] = {
+    {"Enter", "next step"},
+    {"`", "the step before"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+    {"opt ' e", "an accent: \xC3\xA9"},
+};
+
+// irc: IRC
+inline constexpr KeyHelp kIrc[] = {
+    {"Enter", "send the line"},
+    {"Tab", "the next buffer"},
+    {"Alt ; .", "scroll back, forward"},
+    {"Fn ; .", "lines you sent before"},
+    {"Fn , /", "move the cursor"},
+    {"Del", "delete backwards"},
+    {"/settings", "server, nick, passwords"},
+    {"/join #x", "join a channel"},
+    {"/part", "leave it"},
+    {"/msg nick", "a private chat"},
+    {"/me", "an action"},
+    {"/nick", "change your nick"},
+    {"/topic", "see or set the topic"},
+    {"/names", "who is there"},
+    {"/quit", "disconnect, and stay so"},
+    {"/raw", "a line as it is"},
+    {"`", "leave: IRC stays connected"},
+};
+
+// irc-settings: IRC settings
+inline constexpr KeyHelp kIrcSettings[] = {
+    {"; .", "up, down"},
+    {"Enter", "edit, switch, or save"},
+    {"`", "leave without saving"},
+};
+
+// irc-field: IRC, a setting
+inline constexpr KeyHelp kIrcField[] = {
+    {"Enter", "keep it"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+};
+
+// wifi-tools: Wi-Fi Tools
+inline constexpr KeyHelp kWifiTools[] = {
+    {"; .", "up, down"},
+    {"Enter", "open"},
+};
+
+// wifi-networks: Networks nearby
+inline constexpr KeyHelp kWifiNetworks[] = {
+    {"; .", "up, down"},
+    {"Enter", "track its signal"},
+    {"s", "sort: signal, channel, name"},
+    {"o", "open networks only"},
+    {"h", "hide the hidden ones"},
+    {"w", "strong ones only"},
+    {"l", "log the scans to the card"},
+};
+
+// wifi-tracker: Signal tracker
+inline constexpr KeyHelp kWifiTracker[] = {
+    {"m", "clicks on or off"},
+};
+
+// gnss: GNSS
+inline constexpr KeyHelp kGnss[] = {
+    {"Tab", "the position, or the sky"},
+    {"r", "record a Track, or stop it"},
+};
+
+// gemini: Gemini, a page
+inline constexpr KeyHelp kGemini[] = {
+    {"Tab", "the next link"},
+    {"Aa Tab", "the link before"},
+    {"Enter", "follow the link"},
+    {"`  Del", "the page before"},
+    {"; .", "scroll"},
+    {"Space", "a page down"},
+    {", /", "sideways, in wide blocks"},
+    {"g", "type an address"},
+    {"b", "bookmark this page"},
+    {"s", "save the page to the card"},
+    {"S", "...with the pages it links to"},
+};
+
+// gemini-saved: Gemini, a Saved Page
+inline constexpr KeyHelp kGeminiSaved[] = {
+    {"Tab", "the next link"},
+    {"Aa Tab", "the link before"},
+    {"Enter", "follow the link"},
+    {"`  Del", "the page before"},
+    {"; .", "scroll"},
+    {"Space", "a page down"},
+    {", /", "sideways, in wide blocks"},
+    {"g", "type an address"},
+    {"b", "bookmark this page"},
+    {"r", "refresh this Saved Page"},
+    {"d", "delete this Saved Page"},
+};
+
+// gemini-address: Gemini, an address
+inline constexpr KeyHelp kGeminiAddress[] = {
+    {"Enter", "go there"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+};
+
+// gemini-answer: Gemini, an answer to a page
+inline constexpr KeyHelp kGeminiAnswer[] = {
+    {"Enter", "send it"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+};
+
+// lora: LoRa Scanner, the packets
+inline constexpr KeyHelp kLora[] = {
+    {"; .", "up, down"},
+    {"Enter", "the packet's details"},
+    {"p", "pick a Meshtastic preset"},
+    {"c", "start a Capture, or stop it"},
+    {"Tab", "the Sweep"},
+};
+
+// lora-packet: LoRa Scanner, a packet
+inline constexpr KeyHelp kLoraPacket[] = {
+    {"; .", "scroll"},
+    {"Enter", "back to the list"},
+};
+
+// lora-presets: LoRa Scanner, the presets
+inline constexpr KeyHelp kLoraPresets[] = {
+    {"; .", "up, down"},
+    {"Enter", "listen with this preset"},
+};
+
+// lora-sweep: LoRa Scanner, the Sweep
+inline constexpr KeyHelp kLoraSweep[] = {
+    {"Tab", "the Sniffer"},
+};
+
+// storage: Storage, a folder
+inline constexpr KeyHelp kStorage[] = {
+    {"; .", "up, down"},
+    {"Enter", "open the folder or the file"},
+    {", /", "a page up, down"},
+    {"c  x", "copy, cut"},
+    {"v", "paste here"},
+    {"r", "rename"},
+    {"d  Del", "delete, after asking"},
+    {"n", "a new folder"},
+    {"i", "details: size, date, type"},
+    {"s", "sort: name, date, size"},
+    {"m", "Maintenance: clean-up, erase"},
+    {"`", "the folder above"},
+};
+
+// storage-details: Storage, an item's details
+inline constexpr KeyHelp kStorageDetails[] = {
+    {"; .", "scroll"},
+    {"Enter", "back to the folder"},
+};
+
+// storage-name: Storage, a name
+inline constexpr KeyHelp kStorageName[] = {
+    {"Enter", "rename it, or make the folder"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+};
+
+// storage-busy: Storage, while it copies or deletes
+inline constexpr KeyHelp kStorageBusy[] = {
+    {"`", "stop the copy or the delete"},
+};
+
+// maintenance: Storage, Maintenance
+inline constexpr KeyHelp kMaintenance[] = {
+    {"; .", "up, down"},
+    {"Enter", "open, or choose"},
+};
+
+// viewer-text: A file, as text
+inline constexpr KeyHelp kViewerText[] = {
+    {"; .", "a line up, down"},
+    {", /", "a page up, down"},
+    {"t  b", "the top, the end"},
+    {"e", "edit it (up to 16 KB)"},
+    {"Tab", "the file as hex, or back"},
+};
+
+// viewer-hex: A file, as hex
+inline constexpr KeyHelp kViewerHex[] = {
+    {"; .", "a line up, down"},
+    {", /", "a page up, down"},
+    {"t  b", "the top, the end"},
+    {"Tab", "the file as text, or back"},
+};
+
+// viewer-pcap: A Capture
+inline constexpr KeyHelp kViewerPcap[] = {
+    {"; .", "up, down"},
+    {"Enter", "the packet"},
+    {", /", "a page up, down"},
+    {"Tab", "the file as hex"},
+};
+
+// viewer-packet: A Capture's packet
+inline constexpr KeyHelp kViewerPacket[] = {
+    {"; .", "scroll"},
+    {"Enter", "back to the packets"},
+};
+
+// viewer-gpx: A Track
+inline constexpr KeyHelp kViewerGpx[] = {
+    {"Tab", "the file as text"},
+};
+
+// viewer-ota: An Update File
+inline constexpr KeyHelp kViewerOta[] = {
+    {"Enter", "install it, if it's genuine"},
+    {"Tab", "the file as hex"},
+};
+
+// notes: Notes, the list
+inline constexpr KeyHelp kNotes[] = {
+    {"; .", "up, down"},
+    {"Enter", "open the note"},
+    {", /", "a page up, down"},
+    {"n", "a new note"},
+    {"r", "rename its file"},
+    {"d  Del", "delete it"},
+    {"s", "sort: newest, or by name"},
+};
+
+// notes-editor: Notes, the editor
+inline constexpr KeyHelp kNotesEditor[] = {
+    {"Enter", "a new line"},
+    {"Del", "delete backwards"},
+    {"Tab", "two spaces"},
+    {"Fn ; . , /", "move the cursor"},
+    {"Alt Fn ; .", "a page up, down"},
+    {"Ctrl a  e", "start, end of the line"},
+    {"opt ' e", "an accent: \xC3\xA9"},
+    {"`", "done: it saves by itself"},
+};
+
+// notes-name: Notes, a file name
+inline constexpr KeyHelp kNotesName[] = {
+    {"Enter", "rename the file"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+};
+
+// shell: Shell
+inline constexpr KeyHelp kShell[] = {
+    {"Enter", "run the line"},
+    {"Tab", "complete: a command, a path"},
+    {"* ?", "several files: /notes/*.txt"},
+    {"Fn ; .", "lines you typed before"},
+    {"Alt ; .", "scroll back, forward"},
+    {"Ctrl b", "your replies only, or all"},
+    {"Fn , /", "move the cursor"},
+    {"Del", "delete backwards"},
+    {"help", "every command"},
+    {"clear", "an empty screen"},
+    {"Notes", "an App, by its name"},
+    {"rm -rf", "delete without being asked"},
+    {"quit  `", "leave the Shell"},
+};
+
+// system: System, any view
+inline constexpr KeyHelp kSystem[] = {
+    {"Tab", "the next view"},
+    {"Aa Tab", "the view before"},
+};
+
+// system-tasks: System, the tasks
+inline constexpr KeyHelp kSystemTasks[] = {
+    {"Tab", "the next view"},
+    {"Aa Tab", "the view before"},
+    {"; .", "scroll"},
+    {"s", "sort: cpu, stack, name"},
+};
+
+// system-system: System, the system view
+inline constexpr KeyHelp kSystemSystem[] = {
+    {"Tab", "the next view"},
+    {"Aa Tab", "the view before"},
+    {"; .", "scroll"},
+};
+
+// settings: Settings
+inline constexpr KeyHelp kSettings[] = {
+    {"; .", "up, down"},
+    {"Enter", "edit, or open the page"},
+    {", /", "change a switch or a slider"},
+};
+
+// settings-choice: Settings, a choice
+inline constexpr KeyHelp kSettingsChoice[] = {
+    {"; .", "up, down"},
+    {"Enter", "choose it"},
+};
+
+// wifi: Settings, Wi-Fi
+inline constexpr KeyHelp kWifi[] = {
+    {"; .", "up, down"},
+    {"Enter", "open, or change"},
+    {", /", "switch Wi-Fi on or off"},
+};
+
+// wifi-servers: Settings, DNS and NTP
+inline constexpr KeyHelp kWifiServers[] = {
+    {"; .", "up, down"},
+    {"Enter", "edit"},
+    {", /", "Always use my DNS: on, off"},
+};
+
+// wifi-network: Settings, a saved network
+inline constexpr KeyHelp kWifiNetwork[] = {
+    {"; .", "up, down"},
+    {"Enter", "edit, or forget"},
+    {", /", "Automatic or Fixed"},
+};
+
+// wifi-status: Settings, the Wi-Fi status
+inline constexpr KeyHelp kWifiStatus[] = {
+    {"Enter", "back"},
+};
+
+// wifi-scan: Settings, adding a network
+inline constexpr KeyHelp kWifiScan[] = {
+    {"; .", "up, down"},
+    {"Enter", "choose this network"},
+};
+
+// wifi-name: Settings, a hidden network's name
+inline constexpr KeyHelp kWifiName[] = {
+    {"Enter", "next: the password"},
+    {"`", "cancel"},
+    {"Del", "delete backwards"},
+    {"Fn , /", "move the cursor"},
+};
+
+// firmware: Settings, Firmware
+inline constexpr KeyHelp kFirmware[] = {
+    {"; .", "up, down"},
+    {"Enter", "check, open, or install"},
+    {"c", "look for a newer release"},
+};
+
+// firmware-release: Settings, a release
+inline constexpr KeyHelp kFirmwareRelease[] = {
+    {"; .", "scroll"},
+    {"Enter", "install it"},
+    {"c", "check again"},
+};
+
+// firmware-older: Settings, older releases
+inline constexpr KeyHelp kFirmwareOlder[] = {
+    {"; .", "up, down"},
+    {"Enter", "its details"},
+    {"c", "read the list again"},
+};
+
+// debug-console: Settings, Debug Console
+inline constexpr KeyHelp kDebugConsole[] = {
+    {"; .", "up, down"},
+    {"Enter", "switch, or open"},
+    {", /", "switch the console on or off"},
+};
+
+// demo: The widget demo
+inline constexpr KeyHelp kDemo[] = {
+    {"; .", "up, down"},
+    {"Enter", "try the widget"},
+};
+
+}  // namespace roro::keys

lib/core/src/app_manager.cpp

@@ -1,5 +1,7 @@
 #include "app_manager.h"
 
+#include "app_keys.h"
+
 #include <cstring>
 
 namespace roro {
@@ -52,6 +54,22 @@ void AppManager::endModal() {
 }
 
 void AppManager::handleKey(const KeyEvent& event) {
+    if (help_.isOpen()) {  // scrolls or closes; nothing reaches the App, Home included
+        help_.onKey(event);
+        redraw_ = true;
+        return;
+    }
+    if (event.key == Key::Help) {
+        std::vector<KeyHelp> rows;
+        foreground_->help(rows);
+        rows.push_back({"Everywhere", nullptr});
+        keys::add(rows, keys::kEverywhere);
+        const char* scope = foreground_->helpTitle();
+        const char* app = foregroundTitle();
+        help_.open(scope ? scope : app ? app : "Launcher", std::move(rows));
+        redraw_ = true;
+        return;
+    }
     if (modal_) {
         foreground_->onKey(event);
         return;
@@ -64,6 +82,19 @@ void AppManager::handleKey(const KeyEvent& event) {
     if (!consumed && event.key == Key::Back) home();
 }
 
+std::string AppManager::commandFor(const char* id) {
+    std::string command;
+    for (const char* p = id; *p && *p != '-'; p++) command += *p;
+    if (!command.empty() && command[0] >= 'a' && command[0] <= 'z') command[0] = static_cast<char>(command[0] - 'a' + 'A');
+    return command;
+}
+
+const AppInfo* AppManager::byCommand(const std::string& command) const {
+    for (auto& info : apps_)
+        if (!info.hidden && commandFor(info.id) == command) return &info;
+    return nullptr;
+}
+
 const char* AppManager::foregroundTitle() const {
     for (auto& info : apps_)
         if (info.app == foreground_) return info.title;
@@ -77,6 +108,7 @@ bool AppManager::takeRedraw() {
 }
 
 void AppManager::switchTo(App& app) {
+    help_.close();  // an App opened from elsewhere (a Notification, a command): its keys, not the last one's
     if (&app == foreground_) return;
     foreground_->onExit();
     foreground_ = &app;

lib/core/src/app_manager.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <string>
 #include <vector>
 
 #include "app.h"
@@ -34,9 +35,19 @@ class AppManager {
     void handleKey(const KeyEvent& event);
     void update(uint32_t nowMs) { foreground_->update(nowMs); }
 
+    // The command that opens an App from the consoles and the Shell (issue #67): its id with a
+    // capital letter, up to the first dash. "notes" is Notes, "wifi-tools" is Wifi. The capital says
+    // "an App", where every command of the firmware is in small letters.
+    static std::string commandFor(const char* id);
+    // The App that command names, among the ones the Launcher lists; nullptr if there's none.
+    const AppInfo* byCommand(const std::string& command) const;
+
     App& foreground() const { return *foreground_; }
     const char* foregroundTitle() const;  // nullptr for the Launcher
 
+    // The help panel (Fn+h): open, it takes every key, and the App sees none of them.
+    const HelpModel& help() const { return help_; }
+
     // True once after the screen needs redrawing (App switch, or the App asked for it).
     bool takeRedraw();
 
@@ -47,6 +58,7 @@ class AppManager {
     App& launcher_;
     App* foreground_;
     std::vector<AppInfo> apps_;
+    HelpModel help_;
     bool redraw_ = true;
     bool modal_ = false;
 };

lib/core/src/key_event.h

@@ -16,6 +16,7 @@ enum class Key : uint8_t {
     Home,
     Tab,
     Delete,
+    Help,  // Fn+h anywhere, or ? outside Text Entry: the keys of this screen (issue #69)
 };
 
 struct KeyEvent {

lib/core/src/key_help.h

@@ -0,0 +1,63 @@
+#pragma once
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include "key_event.h"
+
+// The help panel (issue #69, docs/milestones/U1.md): Fn+h on any screen lists the keys that work
+// there. Every App says what its keys are in the state it's in; nothing on a screen names keys.
+namespace roro {
+
+// One line of the panel: a key (or keys) and what it does. A line with no action is a heading.
+struct KeyHelp {
+    const char* keys;
+    const char* action;
+};
+
+
+// The panel itself: what it lists, and how far it's scrolled. The keys it takes while open are the
+// arrows; any other key closes it, and none reaches the App.
+class HelpModel {
+   public:
+    explicit HelpModel(int visibleRows = 8) : visible_(visibleRows) {}
+
+    void open(const std::string& title, std::vector<KeyHelp> rows) {
+        title_ = title;
+        rows_ = std::move(rows);
+        top_ = 0;
+        open_ = true;
+    }
+    void close() {
+        open_ = false;
+        rows_.clear();
+        rows_.shrink_to_fit();  // nothing is kept while it's closed
+    }
+    bool isOpen() const { return open_; }
+
+    void onKey(const KeyEvent& e) {
+        int last = std::max(0, static_cast<int>(rows_.size()) - visible_);
+        switch (e.key) {
+            case Key::Up: top_ = std::max(0, top_ - 1); break;
+            case Key::Down: top_ = std::min(last, top_ + 1); break;
+            case Key::Left: top_ = std::max(0, top_ - visible_); break;
+            case Key::Right: top_ = std::min(last, top_ + visible_); break;
+            default: close(); break;
+        }
+    }
+
+    const std::string& title() const { return title_; }
+    const std::vector<KeyHelp>& rows() const { return rows_; }
+    int top() const { return top_; }
+    int visibleRows() const { return visible_; }
+
+   private:
+    std::string title_;
+    std::vector<KeyHelp> rows_;
+    int top_ = 0;
+    int visible_;
+    bool open_ = false;
+};
+
+}  // namespace roro

lib/debug/src/debug_auth.cpp

@@ -0,0 +1,117 @@
+#include "debug_auth.h"
+
+#include <cstring>
+
+#include "sha256.h"
+
+namespace roro::debug {
+
+namespace {
+const char kAlphabet[] = "0123456789ABCDEFGHJKMNPQRSTVWXYZ";
+}
+
+std::string makeToken(const uint8_t random[kTokenRandom]) {
+    std::string token;
+    uint32_t bits = 0;
+    int have = 0;
+    size_t next = 0;
+    while (token.size() < kTokenChars) {
+        if (have < 5) {
+            bits = (bits << 8) | random[next++];
+            have += 8;
+        }
+        token += kAlphabet[(bits >> (have - 5)) & 31];
+        have -= 5;
+    }
+    return token;
+}
+
+std::string tidyToken(const std::string& typed) {
+    std::string out;
+    for (char c : typed) {
+        if (c == '-' || c == ' ' || c == '\t' || c == '\r' || c == '\n') continue;
+        if (c >= 'a' && c <= 'z') c = static_cast<char>(c - 'a' + 'A');
+        // Crockford's rule for the letters his alphabet leaves out: read as the digit they look like.
+        if (c == 'O') c = '0';
+        if (c == 'I' || c == 'L') c = '1';
+        out += c;
+    }
+    return out;
+}
+
+bool validToken(const std::string& tidied) {
+    if (tidied.size() < kMinTokenChars || tidied.size() > kMaxTokenChars) return false;
+    for (char c : tidied)
+        if (c <= ' ' || c > '~' || c == '-' || (c >= 'a' && c <= 'z') || c == 'O' || c == 'I' || c == 'L') return false;
+    return true;
+}
+
+std::string groupToken(const std::string& token) {
+    std::string out;
+    for (size_t i = 0; i < token.size(); i++) {
+        if (i && i % 4 == 0) out += '-';
+        out += token[i];
+    }
+    return out;
+}
+
+void hmacSha256(const uint8_t* key, size_t keyLen, const uint8_t* message, size_t messageLen, uint8_t out[32]) {
+    uint8_t block[64] = {};
+    if (keyLen > sizeof block) Sha256::hash(key, keyLen, block);  // a long key is hashed first
+    else memcpy(block, key, keyLen);
+
+    uint8_t pad[64];
+    for (size_t i = 0; i < sizeof pad; i++) pad[i] = block[i] ^ 0x36;
+    uint8_t inner[32];
+    Sha256 in;
+    in.update(pad, sizeof pad);
+    in.update(message, messageLen);
+    in.finish(inner);
+
+    for (size_t i = 0; i < sizeof pad; i++) pad[i] = block[i] ^ 0x5c;
+    Sha256 outer;
+    outer.update(pad, sizeof pad);
+    outer.update(inner, sizeof inner);
+    outer.finish(out);
+}
+
+std::string toHex(const uint8_t* data, size_t len) {
+    static const char digits[] = "0123456789abcdef";
+    std::string out;
+    out.reserve(len * 2);
+    for (size_t i = 0; i < len; i++) {
+        out += digits[data[i] >> 4];
+        out += digits[data[i] & 15];
+    }
+    return out;
+}
+
+std::string answerFor(const std::string& token, const uint8_t nonce[kNonceBytes]) {
+    uint8_t mac[32];
+    hmacSha256(reinterpret_cast<const uint8_t*>(token.data()), token.size(), nonce, kNonceBytes, mac);
+    return toHex(mac, sizeof mac);
+}
+
+bool sameText(const std::string& a, const std::string& b) {
+    uint8_t diff = a.size() != b.size();
+    for (size_t i = 0; i < b.size(); i++) diff |= static_cast<uint8_t>((i < a.size() ? a[i] : 0) ^ b[i]);
+    return diff == 0;
+}
+
+bool AuthGate::locked(uint32_t nowMs) {
+    if (locked_ && nowMs - lockedAtMs_ >= kLockMs) {  // unsigned: right across the 49-day wrap too
+        locked_ = false;
+        failures_ = 0;
+    }
+    return locked_;
+}
+
+bool AuthGate::failed(uint32_t nowMs) {
+    if (locked(nowMs)) return false;
+    if (++failures_ < kMaxFailures) return false;
+    locked_ = true;
+    lockedAtMs_ = nowMs;
+    return true;
+}
+
+}  // namespace roro::debug

lib/debug/src/debug_auth.h

@@ -0,0 +1,59 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+
+// Who may use the Debug Console (ADR 0010): a token that only the device and its owner know, proved
+// with a challenge and an answer so that it never crosses the network, and a pause after wrong answers.
+namespace roro::debug {
+
+constexpr size_t kTokenChars = 20;     // a token the device makes: 100 bits
+constexpr size_t kTokenRandom = 13;    // the random bytes it takes
+constexpr size_t kMinTokenChars = 16;  // a token typed by hand, once tidied
+constexpr size_t kMaxTokenChars = 64;
+constexpr size_t kNonceBytes = 16;
+
+// A token from random bytes: 20 characters of Crockford's base32 (no I, L, O or U to misread).
+std::string makeToken(const uint8_t random[kTokenRandom]);
+
+// What a person typed, as it's stored and compared: no dashes or spaces, in capitals, and with O
+// read as 0, I and L as 1. So a token can be read off the screen in groups, typed in any case,
+// and the usual misreadings don't matter.
+std::string tidyToken(const std::string& typed);
+
+// A tidied token that may be stored: 16 to 64 printable ASCII characters, as tidyToken leaves them.
+bool validToken(const std::string& tidied);
+
+// For the screen: K7QF-3M2X-9WBD-HT4P-6RNC.
+std::string groupToken(const std::string& token);
+
+void hmacSha256(const uint8_t* key, size_t keyLen, const uint8_t* message, size_t messageLen, uint8_t out[32]);
+
+std::string toHex(const uint8_t* data, size_t len);
+
+// What a client must send back for a challenge: HMAC-SHA256 of the nonce, keyed by the token, in hex.
+std::string answerFor(const std::string& token, const uint8_t nonce[kNonceBytes]);
+
+// Compares without stopping at the first difference, so timing says nothing about the answer.
+bool sameText(const std::string& a, const std::string& b);
+
+// Five wrong answers in a row, from anyone, and nobody is listened to for a minute.
+class AuthGate {
+   public:
+    static constexpr int kMaxFailures = 5;
+    static constexpr uint32_t kLockMs = 60000;
+
+    bool locked(uint32_t nowMs);
+    // A wrong answer. True if it's the one that starts the pause.
+    bool failed(uint32_t nowMs);
+    void succeeded() { failures_ = 0; }
+    int failures() const { return failures_; }
+
+   private:
+    int failures_ = 0;
+    bool locked_ = false;
+    uint32_t lockedAtMs_ = 0;
+};
+
+}  // namespace roro::debug

lib/files/src/file_list.cpp

@@ -0,0 +1,137 @@
+#include "file_list.h"
+
+#include <algorithm>
+#include <cctype>
+#include <cstdio>
+#include <cstring>
+#include <ctime>
+
+namespace roro::files {
+
+namespace {
+
+// Names compare letters only, whatever the case; ties by the bytes, so the order is total.
+int compareNames(const char* a, const char* b) {
+    for (const char *x = a, *y = b;; ++x, ++y) {
+        int cx = std::tolower(static_cast<unsigned char>(*x)), cy = std::tolower(static_cast<unsigned char>(*y));
+        if (cx != cy) return cx < cy ? -1 : 1;
+        if (!cx) break;
+    }
+    return std::strcmp(a, b);
+}
+
+constexpr uint32_t kYear2020 = 1577836800;
+
+std::string sizeText(uint32_t bytes) {
+    char s[16];
+    if (bytes < 1024) std::snprintf(s, sizeof s, "%u B", static_cast<unsigned>(bytes));
+    else if (bytes < 10 * 1024) std::snprintf(s, sizeof s, "%.1f KB", bytes / 1024.0);
+    else if (bytes < 1024 * 1024) std::snprintf(s, sizeof s, "%u KB", static_cast<unsigned>(bytes / 1024));
+    else if (bytes < 10u * 1024 * 1024) std::snprintf(s, sizeof s, "%.1f MB", bytes / 1048576.0);
+    else if (bytes < 1024u * 1024 * 1024) std::snprintf(s, sizeof s, "%u MB", static_cast<unsigned>(bytes / 1048576));
+    else std::snprintf(s, sizeof s, "%.1f GB", bytes / 1073741824.0);
+    return s;
+}
+
+}  // namespace
+
+void FileList::clear() {
+    std::vector<Entry>().swap(entries_);
+    std::vector<uint16_t>().swap(order_);
+    std::vector<char>().swap(names_);
+    more_ = wasted_ = 0;
+}
+
+bool FileList::before(const Entry& a, const Entry& b, FileSort by) const {
+    if (a.folder != b.folder) return a.folder;
+    if (!a.folder) {
+        if (by == FileSort::Date && a.modified != b.modified) return a.modified > b.modified;
+        if (by == FileSort::Size && a.size != b.size) return a.size > b.size;
+    }
+    return compareNames(names_.data() + a.name, names_.data() + b.name) < 0;
+}
+
+void FileList::add(const char* name, uint32_t size, uint32_t modified, bool folder) {
+    size_t len = std::strlen(name) + 1;
+    if (entries_.size() >= kMax) {
+        // Full: the new entry takes the place of the one that sorts last by name, if it sorts
+        // before it. The old name's bytes stay in the buffer until there's enough waste to pack.
+        more_++;
+        size_t last = 0;
+        for (size_t i = 1; i < entries_.size(); i++)
+            if (before(entries_[last], entries_[i], FileSort::Name)) last = i;
+        Entry candidate{static_cast<uint32_t>(names_.size()), size, modified, folder};
+        names_.insert(names_.end(), name, name + len);
+        if (!before(candidate, entries_[last], FileSort::Name)) {
+            names_.resize(names_.size() - len);
+            return;
+        }
+        wasted_ += std::strlen(names_.data() + entries_[last].name) + 1;
+        entries_[last] = candidate;
+        if (wasted_ > 2048) compact();
+        return;
+    }
+    if (entries_.empty()) {
+        entries_.reserve(32);
+        names_.reserve(512);
+    }
+    entries_.push_back({static_cast<uint32_t>(names_.size()), size, modified, folder});
+    names_.insert(names_.end(), name, name + len);
+    order_.push_back(static_cast<uint16_t>(order_.size()));
+}
+
+void FileList::compact() {
+    std::vector<char> packed;
+    packed.reserve(names_.size() - wasted_);
+    for (Entry& e : entries_) {
+        const char* n = names_.data() + e.name;
+        e.name = static_cast<uint32_t>(packed.size());
+        packed.insert(packed.end(), n, n + std::strlen(n) + 1);
+    }
+    names_.swap(packed);
+    wasted_ = 0;
+}
+
+void FileList::sort(FileSort by) {
+    if (wasted_) compact();
+    names_.shrink_to_fit();
+    entries_.shrink_to_fit();
+    order_.resize(entries_.size());
+    for (size_t i = 0; i < order_.size(); i++) order_[i] = static_cast<uint16_t>(i);
+    std::sort(order_.begin(), order_.end(), [&](uint16_t a, uint16_t b) { return before(entries_[a], entries_[b], by); });
+}
+
+int FileList::find(const std::string& name) const {
+    for (size_t i = 0; i < order_.size(); i++)
+        if (name == this->name(i)) return static_cast<int>(i);
+    return -1;
+}
+
+size_t FileList::bytes() const {
+    return entries_.capacity() * sizeof(Entry) + order_.capacity() * sizeof(uint16_t) + names_.capacity();
+}
+
+std::string formatStamp(uint32_t modified) {
+    if (modified < kYear2020) return "-";
+    time_t t = static_cast<time_t>(modified);
+    struct tm local;
+    localtime_r(&t, &local);
+    char s[20];
+    std::snprintf(s, sizeof s, "%04d-%02d-%02d %02d:%02d", local.tm_year + 1900, local.tm_mon + 1, local.tm_mday, local.tm_hour,
+                  local.tm_min);
+    return s;
+}
+
+std::string rowDetail(bool folder, uint32_t size, uint32_t modified) {
+    if (folder) return "folder";
+    std::string stamp = formatStamp(modified);
+    return sizeText(size) + "  " + (stamp == "-" ? stamp : stamp.substr(0, 10));
+}
+
+std::string fitName(const std::string& name, size_t maxChars) {
+    if (name.size() <= maxChars || maxChars < 8) return name.substr(0, maxChars);
+    size_t tail = std::min<size_t>(6, maxChars / 3), head = maxChars - tail - 2;
+    return name.substr(0, head) + ".." + name.substr(name.size() - tail);
+}
+
+}  // namespace roro::files

lib/files/src/file_list.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace roro::files {
+
+enum class FileSort : uint8_t { Name, Date, Size };
+
+// A folder's entries for the Storage App (F1, Q129, Q136): 256 at most, the names packed into
+// one buffer, about 10 KB when full. A bigger folder keeps the first 256 by name, whatever order
+// the card lists them in, and counts the rest.
+class FileList {
+   public:
+    static constexpr size_t kMax = 256;
+
+    void clear();
+    void add(const char* name, uint32_t size, uint32_t modified, bool folder);
+    void sort(FileSort by);  // folders first, by name; then files by name, newest or biggest first
+
+    size_t count() const { return entries_.size(); }
+    size_t more() const { return more_; }  // entries that didn't fit
+    // By position after sort().
+    const char* name(size_t i) const { return names_.data() + entries_[order_[i]].name; }
+    uint32_t size(size_t i) const { return entries_[order_[i]].size; }
+    uint32_t modified(size_t i) const { return entries_[order_[i]].modified; }  // Unix time, 0 if unknown
+    bool folder(size_t i) const { return entries_[order_[i]].folder; }
+    int find(const std::string& name) const;  // position, or -1
+    size_t bytes() const;                     // memory held
+
+   private:
+    struct Entry {
+        uint32_t name;  // offset into names_
+        uint32_t size, modified;
+        bool folder;
+    };
+    bool before(const Entry& a, const Entry& b, FileSort by) const;
+    void compact();
+
+    std::vector<Entry> entries_;
+    std::vector<uint16_t> order_;
+    std::vector<char> names_;
+    size_t more_ = 0, wasted_ = 0;
+};
+
+// What a row shows on the right (Q129): "folder", or "1.2 KB  2026-10-05". A file dated before
+// 2020 was written before the clock was set: "-" (Q137). Local time.
+std::string rowDetail(bool folder, uint32_t size, uint32_t modified);
+std::string formatStamp(uint32_t modified);
+// A name cut to `maxChars` for a row, from the middle: the start and the extension stay readable.
+std::string fitName(const std::string& name, size_t maxChars);  // "2026-10-05 20:00", or "-"
+
+}  // namespace roro::files

lib/files/src/file_names.cpp

@@ -0,0 +1,147 @@
+#include "file_names.h"
+
+#include <cctype>
+
+namespace roro::files {
+
+const char* const kFirmwareFolders[] = {"/irc", "/wifi", "/updates", "/gnss", "/gemini", "/captures", "/notes", "/screenshots"};
+const size_t kFirmwareFolderCount = sizeof kFirmwareFolders / sizeof kFirmwareFolders[0];
+
+std::string parentOf(const std::string& path) {
+    size_t slash = path.rfind('/');
+    return slash == std::string::npos || slash == 0 ? "/" : path.substr(0, slash);
+}
+
+std::string baseName(const std::string& path) {
+    size_t slash = path.rfind('/');
+    return slash == std::string::npos ? path : path.substr(slash + 1);
+}
+
+std::string joinPath(const std::string& folder, const std::string& name) {
+    return folder == "/" ? "/" + name : folder + "/" + name;
+}
+
+std::string extensionOf(const std::string& name) {
+    size_t dot = name.rfind('.');
+    if (dot == std::string::npos || dot == 0) return "";
+    std::string ext = name.substr(dot + 1);
+    for (char& c : ext) c = static_cast<char>(std::tolower(static_cast<unsigned char>(c)));
+    return ext;
+}
+
+bool isInside(const std::string& path, const std::string& folder) {
+    if (folder == "/") return true;
+    if (path.compare(0, folder.size(), folder) != 0) return false;
+    return path.size() == folder.size() || path[folder.size()] == '/';
+}
+
+std::string checkName(const std::string& name) {
+    if (name.empty()) return "A name can't be empty";
+    if (name == "." || name == "..") return "\".\" and \"..\" aren't names";
+    if (name.size() > 64) return "A name can be 64 characters at most";
+    for (char c : name) {
+        if (static_cast<unsigned char>(c) < 0x20) return "A name can't contain control characters";
+        for (char bad : std::string("/\\:*?\"<>|"))
+            if (c == bad) return std::string("A name can't contain ") + c;
+    }
+    if (name.back() == '.' || name.back() == ' ') return "A name can't end with a dot or a space";
+    return "";
+}
+
+std::string whyReadOnly(const std::string& path, const std::vector<std::string>& inUse) {
+    if (path == "/" || path.empty()) return "That's the card itself";
+    if (isInside(path, kGeminiCache)) return std::string(kGeminiCache) + " is the Gemini App's working space";
+    for (const std::string& open : inUse) {
+        if (open == path) return "It's being written right now";
+        if (isInside(open, path)) return "It holds a file that's being written right now";
+    }
+    for (size_t i = 0; i < kFirmwareFolderCount; i++)
+        if (path == kFirmwareFolders[i]) return std::string("The firmware keeps its files in ") + path;
+    return "";
+}
+
+std::string whyNotInto(const std::string& source, const std::string& into) {
+    if (isInside(into, kGeminiCache)) return std::string(kGeminiCache) + " is the Gemini App's working space";
+    if (isInside(into, source)) return "A folder can't go inside itself";
+    if (parentOf(source) == into) return "It's already there";
+    return "";
+}
+
+std::string copyName(const std::string& name, int n) {
+    size_t dot = name.rfind('.');
+    std::string suffix = " (" + std::to_string(n) + ")";
+    if (dot == std::string::npos || dot == 0) return name + suffix;
+    return name.substr(0, dot) + suffix + name.substr(dot);
+}
+
+FileKind kindOf(const std::string& name) {
+    std::string ext = extensionOf(name);
+    if (ext == "gpx") return FileKind::Gpx;
+    if (ext == "pcap") return FileKind::Pcap;
+    if (ext == "ota") return FileKind::Ota;
+    for (const char* text : {"txt", "log", "gmi", "csv", "md", "json", "ini", "conf", "ir"})
+        if (ext == text) return FileKind::Text;
+    return FileKind::Unknown;
+}
+
+bool opensAtEnd(const std::string& name) { return extensionOf(name) == "log"; }
+
+bool looksLikeText(const uint8_t* data, size_t len) {
+    size_t odd = 0;
+    for (size_t i = 0; i < len; i++) {
+        uint8_t b = data[i];
+        if (b == 0) return false;
+        if (b < 0x20 && b != '\n' && b != '\r' && b != '\t') odd++;
+    }
+    return odd * 20 <= len;  // a stray control character or two is still text
+}
+
+RmArgs parseRm(const std::string& args) {
+    RmArgs out;
+    size_t at = 0;
+    while (at < args.size()) {
+        while (at < args.size() && args[at] == ' ') at++;
+        if (at >= args.size() || args[at] != '-') break;
+        size_t end = args.find(' ', at);
+        std::string flags = args.substr(at + 1, end == std::string::npos ? std::string::npos : end - at - 1);
+        bool known = !flags.empty();
+        for (char c : flags) known = known && (c == 'r' || c == 'R' || c == 'f');
+        if (!known) break;  // a name that starts with a dash
+        for (char c : flags) (c == 'f' ? out.force : out.recursive) = true;
+        at = end == std::string::npos ? args.size() : end;
+    }
+    out.path = at < args.size() ? args.substr(at) : "";
+    while (!out.path.empty() && out.path.back() == ' ') out.path.pop_back();
+    return out;
+}
+
+bool hasGlob(const std::string& text) { return text.find_first_of("*?") != std::string::npos; }
+
+bool globMatch(const std::string& pattern, const std::string& name) {
+    auto lower = [](char c) { return c >= 'A' && c <= 'Z' ? static_cast<char>(c - 'A' + 'a') : c; };
+    size_t p = 0, n = 0, star = std::string::npos, mark = 0;
+    while (n < name.size()) {
+        if (p < pattern.size() && (pattern[p] == '?' || lower(pattern[p]) == lower(name[n]))) {
+            p++;
+            n++;
+        } else if (p < pattern.size() && pattern[p] == '*') {
+            star = p++;  // try it as nothing first; come back here to let it take one more
+            mark = n;
+        } else if (star != std::string::npos) {
+            p = star + 1;
+            n = ++mark;
+        } else return false;
+    }
+    while (p < pattern.size() && pattern[p] == '*') p++;
+    return p == pattern.size();
+}
+
+bool splitGlob(const std::string& path, std::string& folder, std::string& pattern) {
+    size_t slash = path.rfind('/');
+    if (slash == std::string::npos) return false;
+    pattern = path.substr(slash + 1);
+    folder = slash == 0 ? "/" : path.substr(0, slash);
+    return hasGlob(pattern) && !hasGlob(folder);
+}
+
+}  // namespace roro::files

lib/files/src/file_names.h

@@ -0,0 +1,58 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace roro::files {
+
+// Paths on the SD card are absolute and use '/': "/gemini/saved/index.gmi".
+std::string parentOf(const std::string& path);    // "/" for a top-level entry and for "/"
+std::string baseName(const std::string& path);    // "" for "/"
+std::string joinPath(const std::string& folder, const std::string& name);
+std::string extensionOf(const std::string& name);  // lower case, without the dot; "" if none
+bool isInside(const std::string& path, const std::string& folder);  // a folder is inside itself
+
+// A name typed for rename or a new folder (F1, Q131): "" if FAT and this App can take it, or why not.
+std::string checkName(const std::string& name);
+
+// The top-level folders the firmware keeps its files in. They can't be renamed or deleted;
+// what's in them can (Q130).
+extern const char* const kFirmwareFolders[];
+extern const size_t kFirmwareFolderCount;
+constexpr const char* kGeminiCache = "/gemini/cache";
+
+// Why `path` can't be renamed, moved or deleted, or "" if it can (Q130). `inUse`: the files the
+// firmware has open right now.
+std::string whyReadOnly(const std::string& path, const std::vector<std::string>& inUse);
+
+// Why `source` can't be copied or moved into the folder `into`, or "" if it can.
+std::string whyNotInto(const std::string& source, const std::string& into);
+
+// "a (2).gmi": the name of a copy made next to its original.
+std::string copyName(const std::string& name, int n);
+
+// Which viewer opens a file (Q134), from its name. Unknown: look at the first bytes.
+enum class FileKind : uint8_t { Text, Gpx, Pcap, Ota, Unknown };
+FileKind kindOf(const std::string& name);
+bool opensAtEnd(const std::string& name);  // logs
+bool looksLikeText(const uint8_t* data, size_t len);
+
+// `rm`'s arguments, as Unix has them (issue #67): -r for a folder and what's in it, -f for no
+// question, alone or together (-rf, -fr, -r -f), then the path, which may hold spaces.
+struct RmArgs {
+    bool recursive = false, force = false;
+    std::string path;
+};
+RmArgs parseRm(const std::string& args);
+
+// Patterns in a path (issue #67): * for any run of characters, ? for one, in the last part of the
+// path only (/notes/*.txt, not /*/a.txt). Cases aren't told apart, as on the card.
+bool hasGlob(const std::string& text);
+bool globMatch(const std::string& pattern, const std::string& name);
+// "/notes/*.txt" taken apart: the folder ("/notes", or "/" at the top) and the pattern ("*.txt").
+// False if there's no pattern in it, or if the folder has one too.
+bool splitGlob(const std::string& path, std::string& folder, std::string& pattern);
+
+}  // namespace roro::files

lib/files/src/file_views.cpp

@@ -0,0 +1,143 @@
+#include "file_views.h"
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#include "file_list.h"
+#include "track.h"
+
+namespace roro::files {
+
+std::string hexRow(uint32_t offset, const uint8_t* data, size_t len) {
+    char head[8];
+    std::snprintf(head, sizeof head, "%05X", static_cast<unsigned>(offset));
+    std::string row = head, text;
+    for (size_t i = 0; i < 8; i++) {
+        if (i % 2 == 0) row += ' ';
+        char hex[3] = "  ";
+        if (i < len) {
+            std::snprintf(hex, sizeof hex, "%02x", data[i]);
+            text += data[i] >= 0x20 && data[i] < 0x7F ? static_cast<char>(data[i]) : '.';
+        }
+        row += hex;
+    }
+    return row + "  " + text;
+}
+
+namespace {
+// Days since 1970-01-01 (Howard Hinnant's days_from_civil): no timegm() everywhere.
+int64_t daysFromCivil(int y, int m, int d) {
+    y -= m <= 2;
+    int64_t era = (y >= 0 ? y : y - 399) / 400;
+    int yoe = static_cast<int>(y - era * 400);
+    int doy = (153 * (m + (m > 2 ? -3 : 9)) + 2) / 5 + d - 1;
+    int doe = yoe * 365 + yoe / 4 - yoe / 100 + doy;
+    return era * 146097 + doe - 719468;
+}
+
+bool attribute(const std::string& element, const char* name, double& out) {
+    size_t at = element.find(name);
+    if (at == std::string::npos) return false;
+    const char* from = element.c_str() + at + std::strlen(name);
+    char* end = nullptr;
+    out = std::strtod(from, &end);
+    return end != from;
+}
+}  // namespace
+
+void GpxSummary::point(const std::string& element) {
+    double lat, lon;
+    if (!attribute(element, "lat=\"", lat) || !attribute(element, "lon=\"", lon)) return;
+    if (points_ > 0) meters_ += gnss::distanceMeters(lat_, lon_, lat, lon);
+    lat_ = lat;
+    lon_ = lon;
+    points_++;
+    size_t at = element.find("<time>");
+    int y, mo, d, h, mi, s;
+    if (at != std::string::npos && std::sscanf(element.c_str() + at + 6, "%d-%d-%dT%d:%d:%d", &y, &mo, &d, &h, &mi, &s) == 6) {
+        int64_t t = daysFromCivil(y, mo, d) * 86400 + h * 3600 + mi * 60 + s;
+        if (first_ == 0) first_ = t;
+        last_ = t;
+    }
+}
+
+void GpxSummary::feed(const char* data, size_t len) {
+    carry_.append(data, len);
+    size_t done = 0;
+    for (;;) {
+        size_t open = carry_.find("<trkpt", done);
+        if (open == std::string::npos) {
+            // Nothing begun, except perhaps the first letters of a tag at the very end.
+            done = carry_.size() > 6 ? carry_.size() - 6 : done;
+            break;
+        }
+        size_t close = carry_.find("</trkpt>", open);
+        size_t next = carry_.find("<trkpt", open + 6);  // a point with nothing inside: <trkpt .../>
+        if (close == std::string::npos && next == std::string::npos) {
+            done = open;
+            break;
+        }
+        size_t end = close != std::string::npos && (next == std::string::npos || close < next) ? close + 8 : next;
+        point(carry_.substr(open, end - open));
+        done = end;
+    }
+    carry_.erase(0, done);
+    if (carry_.size() > 2048) carry_.erase(0, carry_.size() - 6);  // not a GPX point: don't keep it
+}
+
+std::string formatDuration(int64_t seconds) {
+    char s[24];
+    if (seconds < 60) std::snprintf(s, sizeof s, "%d s", static_cast<int>(seconds));
+    else if (seconds < 3600) std::snprintf(s, sizeof s, "%d min %02d s", static_cast<int>(seconds / 60), static_cast<int>(seconds % 60));
+    else std::snprintf(s, sizeof s, "%d h %02d min", static_cast<int>(seconds / 3600), static_cast<int>(seconds % 3600 / 60));
+    return s;
+}
+
+std::vector<std::string> GpxSummary::lines() const {
+    std::vector<std::string> out;
+    out.push_back(std::to_string(points_) + (points_ == 1 ? " point" : " points"));
+    if (first_ > 0) {
+        out.push_back("Started " + formatStamp(static_cast<uint32_t>(first_)));
+        out.push_back("Lasted " + formatDuration(last_ - first_));
+    }
+    char s[32];
+    if (meters_ < 1000) std::snprintf(s, sizeof s, "Distance %.0f m", meters_);
+    else std::snprintf(s, sizeof s, "Distance %.2f km", meters_ / 1000);
+    out.push_back(s);
+    return out;
+}
+
+namespace {
+uint32_t le32(const uint8_t* p) { return p[0] | p[1] << 8 | p[2] << 16 | static_cast<uint32_t>(p[3]) << 24; }
+}  // namespace
+
+PcapHeader parsePcapHeader(const uint8_t* data, size_t len) {
+    PcapHeader h;
+    if (len < kPcapHeaderSize || le32(data) != 0xA1B2C3D4) return h;  // little-endian, microseconds: what we write
+    h.ok = true;
+    h.linkType = le32(data + 20);
+    return h;
+}
+
+bool parsePcapRecord(const uint8_t* data, size_t len, PcapRecord& out) {
+    if (len < kPcapRecordSize) return false;
+    out.seconds = le32(data);
+    out.micros = le32(data + 4);
+    out.length = le32(data + 8);
+    return out.length <= 65535;
+}
+
+bool parseLoraTap(const uint8_t* d, size_t len, lora::RxInfo& out) {
+    if (len < lora::kLoraTapSize || d[0] != 0) return false;
+    out.frequencyHz = static_cast<uint32_t>(d[4]) << 24 | d[5] << 16 | d[6] << 8 | d[7];
+    out.bandwidthKHz = d[8] * 125.0f;
+    out.spreadingFactor = d[9];
+    out.rssi = d[10] - 139.0f;
+    out.noiseFloor = d[12] - 139.0f;
+    out.snr = static_cast<int8_t>(d[13]) / 4.0f;
+    out.syncWord = d[14];
+    return true;
+}
+
+}  // namespace roro::files

lib/files/src/file_views.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+#include "loratap.h"
+
+namespace roro::files {
+
+// What the Storage App's viewers show of the files the firmware writes (F1, Q134).
+
+// One row of a hex dump, eight bytes: "00010 4865 6c6c 6f2c 2077  Hello, w".
+std::string hexRow(uint32_t offset, const uint8_t* data, size_t len);
+
+// A Track (.gpx) read a piece at a time: its points, when it started and ended, how far it went.
+class GpxSummary {
+   public:
+    void feed(const char* data, size_t len);
+
+    uint32_t points() const { return points_; }
+    int64_t start() const { return first_; }  // UTC seconds, 0 if no point carried a time
+    int64_t end() const { return last_; }
+    double meters() const { return meters_; }
+    std::vector<std::string> lines() const;  // for the screen
+
+   private:
+    void point(const std::string& element);
+
+    std::string carry_;  // the part of a point cut by the end of a piece
+    uint32_t points_ = 0;
+    int64_t first_ = 0, last_ = 0;
+    double meters_ = 0, lat_ = 0, lon_ = 0;
+};
+
+// "1 h 02 min", "4 min 10 s", "12 s".
+std::string formatDuration(int64_t seconds);
+
+// A Capture (.pcap): the file's header, then one record after another.
+struct PcapHeader {
+    bool ok = false;
+    uint32_t linkType = 0;  // 270: LoRaTap, what the LoRa Scanner writes
+};
+constexpr size_t kPcapHeaderSize = 24, kPcapRecordSize = 16;
+constexpr uint32_t kLinkLoraTap = 270;
+PcapHeader parsePcapHeader(const uint8_t* data, size_t len);
+
+struct PcapRecord {
+    uint32_t seconds = 0, micros = 0, length = 0;  // length: the bytes that follow in the file
+};
+bool parsePcapRecord(const uint8_t* data, size_t len, PcapRecord& out);  // false: not a record, stop there
+
+// The LoRaTap header a packet starts with; false if `len` is too short for one.
+bool parseLoraTap(const uint8_t* data, size_t len, lora::RxInfo& out);
+
+}  // namespace roro::files

lib/files/src/png_rgb332.cpp

@@ -0,0 +1,118 @@
+#include "png_rgb332.h"
+
+namespace roro::png {
+
+uint32_t crc32(uint32_t crc, const uint8_t* data, size_t len) {
+    crc = ~crc;
+    for (size_t i = 0; i < len; i++) {
+        crc ^= data[i];
+        for (int bit = 0; bit < 8; bit++) crc = (crc >> 1) ^ (0xEDB88320u & (0u - (crc & 1)));
+    }
+    return ~crc;
+}
+
+uint32_t adler32(uint32_t adler, const uint8_t* data, size_t len) {
+    uint32_t a = adler & 0xFFFF, b = adler >> 16;
+    for (size_t i = 0; i < len; i++) {
+        a = (a + data[i]) % 65521;
+        b = (b + a) % 65521;
+    }
+    return (b << 16) | a;
+}
+
+namespace {
+
+void be32(uint8_t* out, uint32_t v) {
+    out[0] = static_cast<uint8_t>(v >> 24);
+    out[1] = static_cast<uint8_t>(v >> 16);
+    out[2] = static_cast<uint8_t>(v >> 8);
+    out[3] = static_cast<uint8_t>(v);
+}
+
+size_t rawSize(int w, int h) { return static_cast<size_t>(w + 1) * h; }  // a filter byte before each row
+size_t idatSize(int w, int h) { return 2 + 5 + rawSize(w, h) + 4; }       // zlib header, block header, data, adler
+
+}  // namespace
+
+size_t Rgb332Writer::fileSize(int w, int h) {
+    return 8 + (12 + 13) + (12 + 768) + (12 + idatSize(w, h)) + 12;  // signature, IHDR, PLTE, IDAT, IEND
+}
+
+bool Rgb332Writer::put(const uint8_t* data, size_t len, bool inIdat) {
+    if (inIdat) crc_ = crc32(crc_, data, len);
+    return sink_(data, len);
+}
+
+bool Rgb332Writer::put32(uint32_t value, bool inIdat) {
+    uint8_t b[4];
+    be32(b, value);
+    return put(b, 4, inIdat);
+}
+
+bool Rgb332Writer::begin() {
+    if (w_ <= 0 || h_ <= 0 || rawSize(w_, h_) > 65535) return false;
+    static const uint8_t signature[] = {0x89, 'P', 'N', 'G', '\r', '\n', 0x1A, '\n'};
+    if (!sink_(signature, sizeof signature)) return false;
+
+    uint8_t ihdr[4 + 13] = {'I', 'H', 'D', 'R'};
+    be32(ihdr + 4, static_cast<uint32_t>(w_));
+    be32(ihdr + 8, static_cast<uint32_t>(h_));
+    ihdr[12] = 8;  // bits a pixel
+    ihdr[13] = 3;  // indexed colour
+    ihdr[14] = ihdr[15] = ihdr[16] = 0;
+    uint8_t word[4];
+    be32(word, 13);
+    if (!sink_(word, 4) || !sink_(ihdr, sizeof ihdr)) return false;
+    be32(word, crc32(0, ihdr, sizeof ihdr));
+    if (!sink_(word, 4)) return false;
+
+    // The palette: every RGB332 value is its own index, as scripts/rdbg.py expands them. Sixteen
+    // colours at a time: this runs on a task with a small stack.
+    be32(word, 768);
+    const uint8_t plteKind[] = {'P', 'L', 'T', 'E'};
+    if (!sink_(word, 4) || !sink_(plteKind, 4)) return false;
+    uint32_t plteCrc = crc32(0, plteKind, 4);
+    for (int first = 0; first < 256; first += 16) {
+        uint8_t piece[48];
+        for (int i = 0; i < 16; i++) {
+            int v = first + i;
+            piece[i * 3] = static_cast<uint8_t>((v >> 5) * 255 / 7);
+            piece[i * 3 + 1] = static_cast<uint8_t>(((v >> 2) & 7) * 255 / 7);
+            piece[i * 3 + 2] = static_cast<uint8_t>((v & 3) * 255 / 3);
+        }
+        plteCrc = crc32(plteCrc, piece, sizeof piece);
+        if (!sink_(piece, sizeof piece)) return false;
+    }
+    be32(word, plteCrc);
+    if (!sink_(word, 4)) return false;
+
+    // IDAT: a zlib stream of one stored block. Its length is known, so it can be written first.
+    size_t raw = rawSize(w_, h_);
+    be32(word, static_cast<uint32_t>(idatSize(w_, h_)));
+    if (!sink_(word, 4)) return false;
+    crc_ = 0;
+    const uint8_t head[] = {'I', 'D', 'A', 'T', 0x78, 0x01, 0x01, static_cast<uint8_t>(raw), static_cast<uint8_t>(raw >> 8),
+                            static_cast<uint8_t>(~raw), static_cast<uint8_t>(~raw >> 8)};
+    return put(head, sizeof head, true);
+}
+
+bool Rgb332Writer::row(const uint8_t* pixels) {
+    if (rows_ >= h_) return false;
+    rows_++;
+    const uint8_t filter = 0;  // none
+    adler_ = adler32(adler_, &filter, 1);
+    adler_ = adler32(adler_, pixels, static_cast<size_t>(w_));
+    return put(&filter, 1, true) && put(pixels, static_cast<size_t>(w_), true);
+}
+
+bool Rgb332Writer::end() {
+    if (rows_ != h_) return false;
+    if (!put32(adler_, true)) return false;
+    uint8_t word[4];
+    be32(word, crc_);
+    if (!sink_(word, 4)) return false;
+    static const uint8_t iend[] = {0, 0, 0, 0, 'I', 'E', 'N', 'D', 0xAE, 0x42, 0x60, 0x82};
+    return sink_(iend, sizeof iend);
+}
+
+}  // namespace roro::png

lib/files/src/png_rgb332.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+
+// A PNG of the screen, written a row at a time with almost no memory (issue #67, Q209): 8-bit
+// indexed colour with the 256 colours of RGB332 as its palette, and the pixels stored, not
+// compressed (a "stored" deflate block), so there is nothing to compress with and nothing to buffer.
+// One block holds at most 65,535 bytes: enough for the 240 x 135 screen (32,535 with its row bytes).
+namespace roro::png {
+
+uint32_t crc32(uint32_t crc, const uint8_t* data, size_t len);      // running; start from 0
+uint32_t adler32(uint32_t adler, const uint8_t* data, size_t len);  // running; start from 1
+
+class Rgb332Writer {
+   public:
+    using Sink = std::function<bool(const uint8_t* data, size_t len)>;  // false: writing failed
+
+    Rgb332Writer(int width, int height, Sink sink) : w_(width), h_(height), sink_(std::move(sink)) {}
+
+    // The file's size, known before a byte is written.
+    static size_t fileSize(int width, int height);
+
+    bool begin();                      // false: too big for one block, or the sink refused
+    bool row(const uint8_t* pixels);   // `width` bytes, RRRGGGBB each
+    bool end();
+
+   private:
+    bool put(const uint8_t* data, size_t len, bool inIdat);
+    bool put32(uint32_t value, bool inIdat);
+
+    int w_, h_, rows_ = 0;
+    Sink sink_;
+    uint32_t crc_ = 0, adler_ = 1;
+};
+
+}  // namespace roro::png

lib/files/src/text_pager.cpp

@@ -0,0 +1,121 @@
+#include "text_pager.h"
+
+#include <algorithm>
+
+namespace roro::files {
+
+TextPager::TextPager(ReadAt read, uint32_t size, int cols, int rows)
+    : read_(std::move(read)), size_(size), cols_(std::max(1, cols)), rows_(std::max(1, rows)) {}
+
+const uint8_t* TextPager::bytes(uint32_t at, size_t& len) {
+    len = 0;
+    if (at >= size_) return nullptr;
+    bool cached = at >= cacheAt_ && at < cacheAt_ + cache_.size();
+    // Wanted: a line's worth ahead, unless the cache already reaches the end of the file.
+    size_t ahead = cached ? cacheAt_ + cache_.size() - at : 0;
+    if (!cached || (ahead < kBlock / 4 && cacheAt_ + cache_.size() < size_)) {
+        cacheAt_ = at - std::min<uint32_t>(at, kBlock / 2);  // room behind too: scrolling back is common
+        cache_.resize(std::min<uint32_t>(kBlock, size_ - cacheAt_));
+        cache_.resize(read_(cacheAt_, cache_.data(), cache_.size()));
+        if (at >= cacheAt_ + cache_.size()) return nullptr;  // the file got shorter, or the card failed
+    }
+    len = cacheAt_ + cache_.size() - at;
+    return cache_.data() + (at - cacheAt_);
+}
+
+int TextPager::byteAt(uint32_t at) {
+    size_t len;
+    const uint8_t* p = bytes(at, len);
+    return p ? *p : -1;
+}
+
+uint32_t TextPager::nextLine(uint32_t at, std::string* text) {
+    size_t len;
+    const uint8_t* p = bytes(at, len);
+    if (text) text->clear();
+    if (!p) return size_;
+    size_t end = len, next = len;  // the line is [0, end); the one after starts at `next`
+    int count = 0;
+    size_t lastSpace = 0;
+    for (size_t i = 0; i < len; i++) {
+        uint8_t b = p[i];
+        if (b == '\n') {
+            end = i;
+            next = i + 1;
+            break;
+        }
+        if ((b & 0xC0) == 0x80) continue;  // inside a UTF-8 character
+        if (count == cols_) {              // one character too many: wrap
+            if (b == ' ') end = i, next = i + 1;
+            else if (lastSpace > 0) end = lastSpace, next = lastSpace + 1;
+            else end = next = i;
+            break;
+        }
+        count++;
+        if (b == ' ') lastSpace = i;
+    }
+    if (text) {
+        size_t n = end > 0 && p[end - 1] == '\r' ? end - 1 : end;
+        text->reserve(n);
+        for (size_t i = 0; i < n; i++) text->push_back(p[i] == '\t' ? ' ' : (p[i] < 0x20 || p[i] == 0x7F) ? '.' : static_cast<char>(p[i]));
+    }
+    return at + static_cast<uint32_t>(std::max<size_t>(next, 1));
+}
+
+uint32_t TextPager::lineBefore(uint32_t at) {
+    if (at == 0) return 0;
+    at = std::min(at, size_);
+    // The paragraph the line before `at` belongs to starts after the newline before it. The byte
+    // just before `at` may be that line's own newline.
+    uint32_t from = at - 1;
+    if (from > 0 && byteAt(from) == '\n') from--;
+    uint32_t limit = at > kLookBack ? at - kLookBack : 0, start = limit;
+    for (uint32_t i = from + 1; i-- > limit;) {
+        if (byteAt(i) == '\n' && i < at - 1) {
+            start = i + 1;
+            break;
+        }
+    }
+    // No newline that near: any character boundary will do as a place to wrap from.
+    while (start > 0 && start < at && (byteAt(start) & 0xC0) == 0x80) start++;
+    for (uint32_t a = start;;) {
+        uint32_t next = nextLine(a, nullptr);
+        if (next >= at) return a;
+        a = next;
+    }
+}
+
+bool TextPager::atEnd() {
+    uint32_t a = top_;
+    for (int i = 0; i < rows_; i++) {
+        a = nextLine(a, nullptr);
+        if (a >= size_) return true;
+    }
+    return false;
+}
+
+void TextPager::down(int n) {
+    for (; n > 0 && !atEnd(); n--) top_ = nextLine(top_, nullptr);
+}
+
+void TextPager::up(int n) {
+    for (; n > 0 && top_ > 0; n--) top_ = lineBefore(top_);
+}
+
+void TextPager::toEnd() {
+    top_ = size_;
+    up(rows_);
+}
+
+std::vector<std::string> TextPager::lines() {
+    std::vector<std::string> out;
+    uint32_t a = top_;
+    for (int i = 0; i < rows_ && a < size_; i++) {
+        std::string text;
+        a = nextLine(a, &text);
+        out.push_back(std::move(text));
+    }
+    return out;
+}
+
+}  // namespace roro::files

lib/files/src/text_pager.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <string>
+#include <vector>
+
+namespace roro::files {
+
+// A text file of any size, shown a screen at a time (F1, Q134): only the part on screen is read,
+// through `read`, about a kilobyte at once. Lines wrap at spaces, `cols` characters wide. Going
+// back a line means finding where the paragraph before started and wrapping it again, so a file
+// reads the same whichever way it was scrolled.
+class TextPager {
+   public:
+    // Reads up to `len` bytes at `offset`; returns how many it got.
+    using ReadAt = std::function<size_t(uint32_t offset, uint8_t* into, size_t len)>;
+
+    TextPager(ReadAt read, uint32_t size, int cols, int rows);
+
+    void toStart() { top_ = 0; }
+    void toEnd();  // the last line at the bottom of the screen
+    void down(int lines = 1);
+    void up(int lines = 1);
+
+    std::vector<std::string> lines();  // what's on screen: tabs as spaces, control characters as dots
+    uint32_t top() const { return top_; }
+    uint32_t size() const { return size_; }
+    bool atEnd();  // the file's last line is on screen
+    int percent() const { return size_ ? static_cast<int>(static_cast<uint64_t>(top_) * 100 / size_) : 0; }
+
+   private:
+    static constexpr size_t kBlock = 1024;       // read at once
+    static constexpr uint32_t kLookBack = 1024;  // how far back a paragraph's start is looked for
+
+    const uint8_t* bytes(uint32_t at, size_t& len);  // what's cached from `at` on
+    int byteAt(uint32_t at);                         // -1 past the end
+    uint32_t nextLine(uint32_t at, std::string* text);  // where the line after the one at `at` starts
+    uint32_t lineBefore(uint32_t at);
+
+    ReadAt read_;
+    uint32_t size_;
+    int cols_, rows_;
+    uint32_t top_ = 0;
+    std::vector<uint8_t> cache_;
+    uint32_t cacheAt_ = 0;
+};
+
+}  // namespace roro::files

lib/gemini/src/gemini_response.cpp

@@ -0,0 +1,59 @@
+#include "gemini_response.h"
+
+#include <cctype>
+
+namespace roro::gemini {
+
+namespace {
+std::string trim(const std::string& s) {
+    size_t a = s.find_first_not_of(" \t"), b = s.find_last_not_of(" \t");
+    return a == std::string::npos ? "" : s.substr(a, b - a + 1);
+}
+std::string lower(std::string s) {
+    for (auto& c : s) c = static_cast<char>(std::tolower(static_cast<unsigned char>(c)));
+    return s;
+}
+}  // namespace
+
+bool parseHeader(const std::string& line, Header& out) {
+    if (line.size() < 2 || !std::isdigit(static_cast<unsigned char>(line[0])) ||
+        !std::isdigit(static_cast<unsigned char>(line[1])))
+        return false;
+    if (line.size() > 2 && line[2] != ' ') return false;
+    std::string meta = line.size() > 3 ? line.substr(3) : "";
+    if (meta.size() > 1024) return false;
+    out.status = (line[0] - '0') * 10 + (line[1] - '0');
+    out.meta = meta;
+    return true;
+}
+
+Category Header::category() const {
+    switch (status / 10) {
+        case 1: return Category::Input;
+        case 2: return Category::Success;
+        case 3: return Category::Redirect;
+        case 4: return Category::TemporaryFailure;
+        case 5: return Category::PermanentFailure;
+        case 6: return Category::ClientCertificate;
+        default: return Category::Unknown;
+    }
+}
+
+std::string Header::mimeType() const {
+    std::string type = lower(trim(meta.substr(0, meta.find(';'))));
+    return type.empty() ? "text/gemini" : type;
+}
+
+std::string Header::parameter(const std::string& name) const {
+    size_t pos = meta.find(';');
+    while (pos != std::string::npos) {
+        size_t next = meta.find(';', pos + 1);
+        std::string item = trim(meta.substr(pos + 1, next == std::string::npos ? std::string::npos : next - pos - 1));
+        size_t eq = item.find('=');
+        if (eq != std::string::npos && lower(trim(item.substr(0, eq))) == lower(name)) return trim(item.substr(eq + 1));
+        pos = next;
+    }
+    return "";
+}
+
+}  // namespace roro::gemini

lib/gemini/src/gemini_response.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <string>
+
+namespace roro::gemini {
+
+enum class Category { Input, Success, Redirect, TemporaryFailure, PermanentFailure, ClientCertificate, Unknown };
+
+// The response header: "<two digits> <meta>", at most 1024 bytes of meta.
+struct Header {
+    int status = 0;
+    std::string meta;
+
+    Category category() const;
+    bool sensitiveInput() const { return status == 11; }
+    // 2x: the MIME type, lower-cased, without parameters ("text/gemini" when meta is empty).
+    std::string mimeType() const;
+    std::string parameter(const std::string& name) const;  // e.g. "charset"
+};
+
+bool parseHeader(const std::string& line, Header& out);
+
+}  // namespace roro::gemini

lib/gemini/src/gemini_url.cpp

@@ -0,0 +1,215 @@
+#include "gemini_url.h"
+
+#include <cctype>
+#include <cstdio>
+#include <cstdlib>
+#include <vector>
+
+#include "storage_paths.h"
+
+namespace roro::gemini {
+
+namespace {
+
+// RFC 3986, appendix B: ^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?
+struct Parts {
+    std::string scheme, authority, path, query, fragment;
+    bool hasScheme = false, hasAuthority = false, hasQuery = false, hasFragment = false;
+};
+
+Parts split(const std::string& s) {
+    Parts p;
+    size_t i = 0;
+    size_t colon = s.find(':');
+    size_t stop = s.find_first_of("/?#");
+    if (colon != std::string::npos && colon > 0 && (stop == std::string::npos || colon < stop)) {
+        p.scheme = s.substr(0, colon);
+        p.hasScheme = true;
+        i = colon + 1;
+    }
+    if (s.compare(i, 2, "//") == 0) {
+        size_t end = s.find_first_of("/?#", i + 2);
+        if (end == std::string::npos) end = s.size();
+        p.authority = s.substr(i + 2, end - i - 2);
+        p.hasAuthority = true;
+        i = end;
+    }
+    size_t end = s.find_first_of("?#", i);
+    if (end == std::string::npos) end = s.size();
+    p.path = s.substr(i, end - i);
+    i = end;
+    if (i < s.size() && s[i] == '?') {
+        end = s.find('#', i);
+        if (end == std::string::npos) end = s.size();
+        p.query = s.substr(i + 1, end - i - 1);
+        p.hasQuery = true;
+        i = end;
+    }
+    if (i < s.size() && s[i] == '#') {
+        p.fragment = s.substr(i + 1);
+        p.hasFragment = true;
+    }
+    return p;
+}
+
+std::string lower(std::string s) {
+    for (auto& c : s) c = static_cast<char>(std::tolower(static_cast<unsigned char>(c)));
+    return s;
+}
+
+// RFC 3986, section 5.2.4.
+std::string removeDotSegments(std::string in) {
+    std::string out;
+    while (!in.empty()) {
+        if (in.compare(0, 3, "../") == 0) in.erase(0, 3);
+        else if (in.compare(0, 2, "./") == 0) in.erase(0, 2);
+        else if (in.compare(0, 3, "/./") == 0) in.replace(0, 3, "/");
+        else if (in == "/.") in = "/";
+        else if (in.compare(0, 4, "/../") == 0 || in == "/..") {
+            in = in == "/.." ? "/" : in.substr(3);
+            size_t slash = out.rfind('/');
+            out.erase(slash == std::string::npos ? 0 : slash);
+        } else if (in == "." || in == "..") in.clear();
+        else {
+            size_t next = in.find('/', in[0] == '/' ? 1 : 0);
+            if (next == std::string::npos) next = in.size();
+            out += in.substr(0, next);
+            in.erase(0, next);
+        }
+    }
+    return out;
+}
+
+// RFC 3986, section 5.2.3.
+std::string merge(const Parts& base, const std::string& refPath) {
+    if (base.hasAuthority && base.path.empty()) return "/" + refPath;
+    size_t slash = base.path.rfind('/');
+    return slash == std::string::npos ? refPath : base.path.substr(0, slash + 1) + refPath;
+}
+
+// RFC 3986, section 5.3.
+std::string recompose(const Parts& p) {
+    std::string out;
+    if (p.hasScheme) out += p.scheme + ":";
+    if (p.hasAuthority) out += "//" + p.authority;
+    out += p.path;
+    if (p.hasQuery) out += "?" + p.query;
+    if (p.hasFragment) out += "#" + p.fragment;
+    return out;
+}
+
+}  // namespace
+
+bool parseUrl(const std::string& text, Url& out) {
+    Parts p = split(text);
+    if (!p.hasScheme || !p.hasAuthority) return false;
+    out = Url();
+    out.scheme = lower(p.scheme);
+    out.authority = p.authority;
+    std::string hostPort = p.authority.substr(p.authority.find('@') == std::string::npos ? 0 : p.authority.find('@') + 1);
+    size_t colon = hostPort.rfind(':');
+    if (colon != std::string::npos && hostPort.find(']', colon) == std::string::npos) {
+        out.port = std::atoi(hostPort.c_str() + colon + 1);
+        hostPort = hostPort.substr(0, colon);
+    }
+    out.host = lower(hostPort);
+    if (out.host.empty()) return false;
+    out.path = p.path;
+    out.query = p.query;
+    out.fragment = p.fragment;
+    out.hasAuthority = true;
+    out.hasQuery = p.hasQuery;
+    out.hasFragment = p.hasFragment;
+    return true;
+}
+
+bool isGemini(const std::string& url) {
+    Parts p = split(url);
+    return p.hasScheme && lower(p.scheme) == "gemini";
+}
+
+std::string resolve(const std::string& baseText, const std::string& refText) {
+    Parts base = split(baseText), r = split(refText), t;
+    if (r.hasScheme) {
+        t = r;
+        t.path = removeDotSegments(r.path);
+    } else {
+        if (r.hasAuthority) {
+            t.authority = r.authority;
+            t.hasAuthority = true;
+            t.path = removeDotSegments(r.path);
+            t.query = r.query;
+            t.hasQuery = r.hasQuery;
+        } else {
+            if (r.path.empty()) {
+                t.path = base.path;
+                t.query = r.hasQuery ? r.query : base.query;
+                t.hasQuery = r.hasQuery || base.hasQuery;
+            } else {
+                t.path = removeDotSegments(r.path[0] == '/' ? r.path : merge(base, r.path));
+                t.query = r.query;
+                t.hasQuery = r.hasQuery;
+            }
+            t.authority = base.authority;
+            t.hasAuthority = base.hasAuthority;
+        }
+        t.scheme = base.scheme;
+        t.hasScheme = base.hasScheme;
+    }
+    t.fragment = r.fragment;
+    t.hasFragment = r.hasFragment;
+    return recompose(t);
+}
+
+std::string requestUrl(const std::string& url) {
+    Url u;
+    if (!parseUrl(url, u)) return url;
+    std::string out = u.scheme + "://" + u.host;
+    if (u.port > 0 && u.port != 1965) out += ":" + std::to_string(u.port);
+    out += u.path.empty() ? "/" : u.path;
+    if (u.hasQuery) out += "?" + u.query;
+    return out;
+}
+
+std::string encodeQuery(const std::string& text) {
+    std::string out;
+    for (unsigned char c : text) {
+        if (std::isalnum(c) || c == '-' || c == '_' || c == '.' || c == '~') out += static_cast<char>(c);
+        else {
+            char buf[4];
+            std::snprintf(buf, sizeof buf, "%%%02X", c);
+            out += buf;
+        }
+    }
+    return out;
+}
+
+std::string savedPath(const std::string& url) {
+    Url u;
+    if (!parseUrl(url, u)) return "/gemini/saved/unknown.gmi";
+    std::string out = "/gemini/saved/" + storage::sanitize(u.host + (u.port > 0 && u.port != 1965 ? "_" + std::to_string(u.port) : ""));
+    std::string path = u.path.empty() ? "/" : u.path;
+    std::vector<std::string> parts;
+    size_t start = 1;
+    while (start <= path.size()) {
+        size_t slash = path.find('/', start);
+        if (slash == std::string::npos) slash = path.size();
+        parts.push_back(path.substr(start, slash - start));
+        start = slash + 1;
+    }
+    if (parts.empty() || parts.back().empty()) {
+        if (!parts.empty()) parts.pop_back();
+        parts.push_back("index");
+    }
+    for (size_t i = 0; i < parts.size(); i++) {
+        std::string name = parts[i];
+        if (i + 1 == parts.size()) {
+            if (u.hasQuery) name += "~" + u.query;
+            if (name.size() < 4 || name.compare(name.size() - 4, 4, ".gmi") != 0) name += ".gmi";
+        }
+        out += "/" + storage::sanitize(name);
+    }
+    return out;
+}
+
+}  // namespace roro::gemini

lib/gemini/src/gemini_url.h

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <string>
+
+namespace roro::gemini {
+
+// A URL split per RFC 3986 (appendix B). For Gemini, the host is lower-cased and the port
+// defaults to 1965.
+struct Url {
+    std::string scheme, authority, host, path, query, fragment;
+    int port = -1;
+    bool hasAuthority = false, hasQuery = false, hasFragment = false;
+    int portOrDefault() const { return port > 0 ? port : 1965; }
+};
+
+// False unless it has a scheme and a host: only absolute URLs are fetched.
+bool parseUrl(const std::string& text, Url& out);
+bool isGemini(const std::string& url);
+// `ref` against `base`, per RFC 3986 section 5.2 (dot segments included).
+std::string resolve(const std::string& base, const std::string& ref);
+// What goes on the wire: no fragment, lower-case host, never an empty path.
+std::string requestUrl(const std::string& url);
+// For input prompts: everything but unreserved characters percent-encoded (UTF-8 bytes).
+std::string encodeQuery(const std::string& text);
+// Where a Saved Page lives (Q82): /gemini/saved/<host>[_<port>]/<path>[~<query>].gmi
+std::string savedPath(const std::string& url);
+
+}  // namespace roro::gemini

lib/gemini/src/gemtext.cpp

@@ -0,0 +1,100 @@
+#include "gemtext.h"
+
+#include <cstdint>
+
+namespace roro::gemini {
+
+namespace {
+std::string trim(const std::string& s) {
+    size_t a = s.find_first_not_of(" \t"), b = s.find_last_not_of(" \t");
+    return a == std::string::npos ? "" : s.substr(a, b - a + 1);
+}
+}  // namespace
+
+GemLine parseGemLine(const std::string& line, bool& pre) {
+    GemLine g;
+    if (line.compare(0, 3, "```") == 0) {
+        g.type = LineType::PreToggle;
+        g.text = trim(line.substr(3));
+        pre = !pre;
+    } else if (pre) {
+        g.type = LineType::Preformatted;
+        g.text = line;
+    } else if (line.compare(0, 2, "=>") == 0) {
+        g.type = LineType::Link;
+        std::string rest = trim(line.substr(2));
+        size_t gap = rest.find_first_of(" \t");
+        g.url = rest.substr(0, gap);
+        g.text = gap == std::string::npos ? "" : trim(rest.substr(gap));
+        if (g.text.empty()) g.text = g.url;
+    } else if (line.compare(0, 3, "###") == 0) {
+        g.type = LineType::Heading3;
+        g.text = trim(line.substr(3));
+    } else if (line.compare(0, 2, "##") == 0) {
+        g.type = LineType::Heading2;
+        g.text = trim(line.substr(2));
+    } else if (line.compare(0, 1, "#") == 0) {
+        g.type = LineType::Heading1;
+        g.text = trim(line.substr(1));
+    } else if (line.compare(0, 2, "* ") == 0) {
+        g.type = LineType::ListItem;
+        g.text = trim(line.substr(2));
+    } else if (line.compare(0, 1, ">") == 0) {
+        g.type = LineType::Quote;
+        g.text = trim(line.substr(1));
+    } else {
+        g.text = line;
+    }
+    return g;
+}
+
+std::vector<GemLine> parseGemtext(const std::string& document) {
+    std::vector<GemLine> lines;
+    bool pre = false;
+    size_t start = 0;
+    while (start < document.size()) {
+        size_t end = document.find('\n', start);
+        if (end == std::string::npos) end = document.size();
+        std::string line = document.substr(start, end - start);
+        if (!line.empty() && line.back() == '\r') line.pop_back();
+        start = end + 1;
+        lines.push_back(parseGemLine(line, pre));
+    }
+    return lines;
+}
+
+std::string displayText(const std::string& s) {
+    std::string out;
+    size_t column = 0;
+    for (size_t i = 0; i < s.size();) {
+        unsigned char c = static_cast<unsigned char>(s[i]);
+        if (c == '\t') {
+            do out += ' ';
+            while (++column % 4);
+            i++;
+            continue;
+        }
+        if (c < 0x80) {
+            out += static_cast<char>(c);
+            i++;
+        } else {
+            int len = (c & 0xE0) == 0xC0 ? 2 : (c & 0xF0) == 0xE0 ? 3 : (c & 0xF8) == 0xF0 ? 4 : 0;
+            bool valid = len > 0 && i + len <= s.size();
+            for (int k = 1; valid && k < len; k++) valid = (static_cast<unsigned char>(s[i + k]) & 0xC0) == 0x80;
+            if (!valid) {
+                out += '?';
+                i++;
+            } else {
+                uint32_t cp = len == 2 ? (c & 0x1F) : len == 3 ? (c & 0x0F) : (c & 0x07);
+                for (int k = 1; k < len; k++) cp = (cp << 6) | (static_cast<unsigned char>(s[i + k]) & 0x3F);
+                if (cp <= 0xFF) out.append(s, i, len);  // Latin-1: the fonts have it
+                else out += '?';
+                i += len;
+            }
+        }
+        column++;
+    }
+    return out;
+}
+
+}  // namespace roro::gemini

lib/gemini/src/gemtext.h

@@ -0,0 +1,25 @@
+#pragma once
+
+#include <string>
+#include <vector>
+
+namespace roro::gemini {
+
+enum class LineType { Text, Link, Heading1, Heading2, Heading3, ListItem, Quote, PreToggle, Preformatted };
+
+// One gemtext line. Link: `url` and its label in `text` (the URL itself without a label).
+// PreToggle: the ``` line, with its alt text. Preformatted: kept exactly.
+struct GemLine {
+    LineType type = LineType::Text;
+    std::string text, url;
+};
+
+// One line; `preformatted` carries the ``` state from line to line (start with false).
+GemLine parseGemLine(const std::string& line, bool& preformatted);
+std::vector<GemLine> parseGemtext(const std::string& document);
+
+// For the Latin-1 fonts (Q79): valid UTF-8 up to U+00FF kept, anything else '?', and tabs
+// expanded to 4-column stops.
+std::string displayText(const std::string& utf8);
+
+}  // namespace roro::gemini

lib/gemini/src/text_buffer.cpp

@@ -0,0 +1,47 @@
+#include "text_buffer.h"
+
+#include <algorithm>
+
+namespace roro::gemini {
+
+void TextBuffer::append(const char* data, size_t len) {
+    bytes_ += len;
+    for (size_t i = 0; i < len; i++) {
+        if (data[i] == '\n') endLine();
+        else partial_ += data[i];
+    }
+}
+
+void TextBuffer::finish() {
+    if (!partial_.empty()) endLine();
+}
+
+void TextBuffer::endLine() {
+    if (!partial_.empty() && partial_.back() == '\r') partial_.pop_back();
+    size_t len = std::min<size_t>(partial_.size(), 0xFFFF);
+    // A line never spans two chunks: a new chunk when it doesn't fit (bigger if the line is).
+    if (chunks_.empty() || chunks_.back().size() + len > chunks_.back().capacity()) {
+        chunks_.emplace_back();
+        chunks_.back().reserve(std::max(kChunk, len));
+    }
+    std::string& chunk = chunks_.back();
+    lines_.push_back({static_cast<uint16_t>(chunks_.size() - 1), static_cast<uint16_t>(chunk.size()),
+                      static_cast<uint16_t>(len)});
+    chunk.append(partial_, 0, len);
+    partial_.clear();
+}
+
+std::string TextBuffer::line(size_t i) const {
+    if (i >= lines_.size()) return "";
+    const Ref& r = lines_[i];
+    return chunks_[r.chunk].substr(r.offset, r.length);
+}
+
+void TextBuffer::clear() {
+    chunks_.clear();
+    lines_.clear();
+    partial_.clear();
+    bytes_ = 0;
+}
+
+}  // namespace roro::gemini

lib/gemini/src/text_buffer.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace roro::gemini {
+
+// A page's text, kept as lines in 4 KB chunks: no large contiguous block (with IRC connected the
+// largest free block is about 31 KB) and no copy when it grows. About 4 bytes per line on top of
+// the text itself. Bytes are fed as they arrive; lines end at LF, a CR before it is dropped.
+class TextBuffer {
+   public:
+    static constexpr size_t kChunk = 4096;
+
+    void append(const char* data, size_t len);
+    void finish();  // the last line, if it has no line end
+    size_t lineCount() const { return lines_.size(); }
+    std::string line(size_t i) const;
+    size_t bytes() const { return bytes_; }
+    void clear();
+
+   private:
+    struct Ref {
+        uint16_t chunk;
+        uint16_t offset;
+        uint16_t length;
+    };
+    void endLine();
+
+    std::vector<std::string> chunks_;
+    std::vector<Ref> lines_;
+    std::string partial_;  // the line being received
+    size_t bytes_ = 0;
+};
+
+}  // namespace roro::gemini

lib/gnss/src/geo_format.cpp

@@ -0,0 +1,50 @@
+#include "geo_format.h"
+
+#include <cmath>
+#include <cstdio>
+
+namespace roro::gnss {
+
+namespace {
+const char* hemisphere(double degrees, bool latitude) {
+    return latitude ? (degrees < 0 ? "S" : "N") : (degrees < 0 ? "W" : "E");
+}
+}  // namespace
+
+std::string formatDecimal(double degrees, bool latitude) {
+    char buf[32];
+    std::snprintf(buf, sizeof buf, "%.5f\xC2\xB0 %s", std::fabs(degrees), hemisphere(degrees, latitude));
+    return buf;
+}
+
+std::string formatDms(double degrees, bool latitude) {
+    // Work in tenths of a second, so rounding carries into minutes and degrees.
+    long tenths = std::lround(std::fabs(degrees) * 36000.0);
+    long d = tenths / 36000, m = tenths / 600 % 60, s10 = tenths % 600;
+    char buf[40];
+    std::snprintf(buf, sizeof buf, "%ld\xC2\xB0 %02ld' %02ld.%ld\" %s", d, m, s10 / 10, s10 % 10,
+                  hemisphere(degrees, latitude));
+    return buf;
+}
+
+std::string maidenhead(double latitude, double longitude) {
+    double lon = std::fmin(std::fmax(longitude + 180.0, 0.0), 359.999999);
+    double lat = std::fmin(std::fmax(latitude + 90.0, 0.0), 179.999999);
+    std::string out;
+    out += static_cast<char>('A' + static_cast<int>(lon / 20));
+    out += static_cast<char>('A' + static_cast<int>(lat / 10));
+    out += static_cast<char>('0' + static_cast<int>(std::fmod(lon, 20) / 2));
+    out += static_cast<char>('0' + static_cast<int>(std::fmod(lat, 10)));
+    out += static_cast<char>('a' + static_cast<int>(std::fmod(lon, 2) * 12));
+    out += static_cast<char>('a' + static_cast<int>(std::fmod(lat, 1) * 24));
+    return out;
+}
+
+SkyPoint skyPosition(int azimuthDeg, int elevationDeg, int cx, int cy, int radius) {
+    int elevation = elevationDeg < 0 ? 0 : elevationDeg > 90 ? 90 : elevationDeg;
+    double r = radius * (90 - elevation) / 90.0;
+    double az = azimuthDeg * M_PI / 180.0;
+    return {cx + static_cast<int>(std::lround(r * std::sin(az))), cy - static_cast<int>(std::lround(r * std::cos(az)))};
+}
+
+}  // namespace roro::gnss

lib/gnss/src/geo_format.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <string>
+
+namespace roro::gnss {
+
+// "50.86920° N": five decimals, about a metre.
+std::string formatDecimal(double degrees, bool latitude);
+// "50° 52' 09.1\" N" (Settings → Coordinates, Q64).
+std::string formatDms(double degrees, bool latitude);
+// The 6-character Maidenhead locator ("JO20ef"), as radio amateurs give their square.
+std::string maidenhead(double latitude, double longitude);
+
+// Where a satellite goes on the Sky view: the zenith in the centre, the horizon on the circle,
+// north up and east right (as seen looking at the sky from above, like a map).
+struct SkyPoint {
+    int x, y;
+};
+SkyPoint skyPosition(int azimuthDeg, int elevationDeg, int cx, int cy, int radius);
+
+}  // namespace roro::gnss

lib/gnss/src/nmea_parser.cpp

@@ -0,0 +1,234 @@
+#include "nmea_parser.h"
+
+#include <cstdlib>
+
+namespace roro::gnss {
+
+namespace {
+
+constexpr double kKmhPerKnot = 1.852;
+
+int hexValue(char c) {
+    if (c >= '0' && c <= '9') return c - '0';
+    if (c >= 'A' && c <= 'F') return c - 'A' + 10;
+    if (c >= 'a' && c <= 'f') return c - 'a' + 10;
+    return -1;
+}
+
+Constellation fromTalker(const std::string& t) {
+    if (t == "GP") return Constellation::Gps;
+    if (t == "GL") return Constellation::Glonass;
+    if (t == "GA") return Constellation::Galileo;
+    if (t == "GB" || t == "BD") return Constellation::BeiDou;
+    if (t == "GQ" || t == "QZ") return Constellation::Qzss;
+    if (t == "GI") return Constellation::Navic;
+    return Constellation::Unknown;  // GN: combined
+}
+
+// GSA's system ID field (NMEA 4.10).
+Constellation fromSystemId(int id) {
+    switch (id) {
+        case 1: return Constellation::Gps;
+        case 2: return Constellation::Glonass;
+        case 3: return Constellation::Galileo;
+        case 4: return Constellation::BeiDou;
+        case 5: return Constellation::Qzss;
+        case 6: return Constellation::Navic;
+        default: return Constellation::Unknown;
+    }
+}
+
+bool number(const std::string& s, double& out) {
+    if (s.empty()) return false;
+    char* end;
+    out = std::strtod(s.c_str(), &end);
+    return *end == '\0';
+}
+
+int integer(const std::string& s, int fallback = 0) {
+    double v;
+    return number(s, v) ? static_cast<int>(v) : fallback;
+}
+
+// "ddmm.mmmm" / "dddmm.mmmm" with its hemisphere letter.
+bool coordinate(const std::string& value, const std::string& hemisphere, double& out) {
+    double raw;
+    if (!number(value, raw) || hemisphere.empty()) return false;
+    int degrees = static_cast<int>(raw / 100);
+    out = degrees + (raw - degrees * 100) / 60.0;
+    if (hemisphere == "S" || hemisphere == "W") out = -out;
+    return true;
+}
+
+// Days since 1970-01-01 for a civil date (Howard Hinnant's algorithm).
+int64_t daysFromCivil(int y, int m, int d) {
+    y -= m <= 2;
+    const int64_t era = (y >= 0 ? y : y - 399) / 400;
+    const unsigned yoe = static_cast<unsigned>(y - era * 400);
+    const unsigned doy = (153 * (m + (m > 2 ? -3 : 9)) + 2) / 5 + d - 1;
+    const unsigned doe = yoe * 365 + yoe / 4 - yoe / 100 + doy;
+    return era * 146097 + static_cast<int64_t>(doe) - 719468;
+}
+
+}  // namespace
+
+const char* constellationName(Constellation c) {
+    switch (c) {
+        case Constellation::Gps: return "GPS";
+        case Constellation::Glonass: return "GLONASS";
+        case Constellation::Galileo: return "Galileo";
+        case Constellation::BeiDou: return "BeiDou";
+        case Constellation::Qzss: return "QZSS";
+        case Constellation::Navic: return "NavIC";
+        default: return "?";
+    }
+}
+
+int64_t GnssState::utcSeconds() const {
+    return daysFromCivil(year, month, day) * 86400 + hour * 3600 + minute * 60 + second;
+}
+
+void NmeaParser::feed(const char* data, size_t len) {
+    for (size_t i = 0; i < len; i++) {
+        char c = data[i];
+        if (c == '\n') {
+            if (!overflow_ && !line_.empty()) {
+                if (onLine) onLine(line_);
+                sentence(line_);
+            }
+            line_.clear();
+            overflow_ = false;
+        } else if (c != '\r') {
+            if (line_.size() >= kMaxLine) overflow_ = true;
+            else line_ += c;
+        }
+    }
+}
+
+bool NmeaParser::sentence(const std::string& line) {
+    size_t star = line.rfind('*');
+    if (line.size() < 7 || line[0] != '$' || star == std::string::npos || star + 3 != line.size()) {
+        bad_++;
+        return false;
+    }
+    uint8_t sum = 0;
+    for (size_t i = 1; i < star; i++) sum ^= static_cast<uint8_t>(line[i]);
+    int hi = hexValue(line[star + 1]), lo = hexValue(line[star + 2]);
+    if (hi < 0 || lo < 0 || sum != (hi << 4 | lo)) {
+        bad_++;
+        return false;
+    }
+    good_++;
+
+    Fields f;
+    size_t start = 1;
+    for (size_t i = 1; i <= star; i++)
+        if (i == star || line[i] == ',') {
+            f.push_back(line.substr(start, i - start));
+            start = i + 1;
+        }
+    if (f[0].size() < 5) return true;
+    std::string talker = f[0].substr(0, 2), type = f[0].substr(f[0].size() - 3);
+    if (type == "RMC") rmc(f);
+    else if (type == "GGA") gga(f);
+    else if (type == "GSA") gsa(f, fromTalker(talker));
+    else if (type == "GSV") gsv(f, fromTalker(talker));
+    return true;
+}
+
+void NmeaParser::rmc(const Fields& f) {
+    if (f.size() < 10) return;
+    bool active = f[2] == "A";
+    double lat, lon;
+    state_.positionValid = active && coordinate(f[3], f[4], lat) && coordinate(f[5], f[6], lon);
+    if (state_.positionValid) {
+        state_.latitude = lat;
+        state_.longitude = lon;
+    }
+    double knots, course;
+    state_.speedKmh = active && number(f[7], knots) ? static_cast<float>(knots * kKmhPerKnot) : 0;
+    state_.courseValid = active && number(f[8], course);
+    if (state_.courseValid) state_.courseDeg = static_cast<float>(course);
+
+    const std::string &t = f[1], &d = f[9];
+    state_.timeValid = active && t.size() >= 6 && d.size() == 6;
+    if (state_.timeValid) {
+        state_.hour = integer(t.substr(0, 2));
+        state_.minute = integer(t.substr(2, 2));
+        state_.second = integer(t.substr(4, 2));
+        state_.day = integer(d.substr(0, 2));
+        state_.month = integer(d.substr(2, 2));
+        state_.year = 2000 + integer(d.substr(4, 2));
+    }
+}
+
+void NmeaParser::gga(const Fields& f) {
+    if (f.size() < 10) return;
+    int quality = integer(f[6]);
+    double lat, lon, hdop, alt;
+    state_.positionValid = quality > 0 && coordinate(f[2], f[3], lat) && coordinate(f[4], f[5], lon);
+    if (state_.positionValid) {
+        state_.latitude = lat;
+        state_.longitude = lon;
+    }
+    state_.satellitesUsed = integer(f[7]);
+    if (number(f[8], hdop)) state_.hdop = static_cast<float>(hdop);
+    state_.altitudeValid = quality > 0 && number(f[9], alt);
+    if (state_.altitudeValid) state_.altitudeM = static_cast<float>(alt);
+}
+
+void NmeaParser::gsa(const Fields& f, Constellation talker) {
+    if (f.size() < 18) return;
+    int mode = integer(f[2], 1);
+    state_.fix = mode == 3 ? FixType::ThreeD : mode == 2 ? FixType::TwoD : FixType::None;
+    Constellation system = f.size() > 18 ? fromSystemId(integer(f[18])) : talker;
+    if (system == Constellation::Unknown) return;  // can't tell whose satellites these are
+    std::set<int>& used = used_[static_cast<int>(system)];
+    used.clear();
+    for (size_t i = 3; i <= 14; i++)
+        if (!f[i].empty()) used.insert(integer(f[i]));
+    rebuildSatellites();
+}
+
+void NmeaParser::gsv(const Fields& f, Constellation talker) {
+    if (f.size() < 4 || talker == Constellation::Unknown) return;
+    int total = integer(f[1]), number = integer(f[2]);
+    size_t extra = f.size() - 4;
+    int signal = extra % 4 == 1 ? integer(f.back()) : 0;  // NMEA 4.10 signal ID, last
+    auto key = std::make_pair(static_cast<int>(talker), signal);
+    std::vector<Satellite>& pending = pending_[key];
+    if (number == 1) pending.clear();
+    for (size_t i = 4; i + 3 < f.size(); i += 4) {
+        Satellite s;
+        s.system = talker;
+        s.prn = integer(f[i]);
+        s.elevation = integer(f[i + 1]);
+        s.azimuth = integer(f[i + 2]);
+        s.snr = integer(f[i + 3], -1);
+        if (s.prn > 0) pending.push_back(s);
+    }
+    if (number == total) {
+        inView_[key] = pending;
+        pending.clear();
+        rebuildSatellites();
+    }
+}
+
+void NmeaParser::rebuildSatellites() {
+    std::vector<Satellite> merged;
+    for (auto& [key, list] : inView_)
+        for (const Satellite& s : list) {
+            Satellite* same = nullptr;
+            for (auto& m : merged)
+                if (m.system == s.system && m.prn == s.prn) same = &m;
+            if (!same) merged.push_back(s);
+            else if (s.snr > same->snr) same->snr = s.snr;
+        }
+    for (auto& s : merged) {
+        auto it = used_.find(static_cast<int>(s.system));
+        s.used = it != used_.end() && it->second.count(s.prn) > 0;
+    }
+    state_.satellites = std::move(merged);
+}
+
+}  // namespace roro::gnss

lib/gnss/src/nmea_parser.h

@@ -0,0 +1,82 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <map>
+#include <set>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace roro::gnss {
+
+enum class Constellation : uint8_t { Unknown, Gps, Glonass, Galileo, BeiDou, Qzss, Navic };
+const char* constellationName(Constellation c);
+
+enum class FixType : uint8_t { None, TwoD, ThreeD };
+
+struct Satellite {
+    Constellation system = Constellation::Unknown;
+    int prn = 0;
+    int elevation = 0;  // degrees above the horizon
+    int azimuth = 0;    // degrees from north, clockwise
+    int snr = -1;       // dB-Hz; -1 when not tracked
+    bool used = false;  // part of the current Fix
+};
+
+// Everything the receiver has said, as of the last sentence (see CONTEXT.md: Fix).
+struct GnssState {
+    FixType fix = FixType::None;
+    bool positionValid = false;
+    double latitude = 0, longitude = 0;  // degrees, south and west negative
+    bool altitudeValid = false;
+    float altitudeM = 0;  // above mean sea level
+    float speedKmh = 0;
+    bool courseValid = false;
+    float courseDeg = 0;
+    int satellitesUsed = 0;
+    float hdop = 99.9f;
+    // UTC, trusted only with a Fix: the receiver reports a time without one, from its own clock.
+    bool timeValid = false;
+    int year = 0, month = 0, day = 0, hour = 0, minute = 0, second = 0;
+    std::vector<Satellite> satellites;  // in view, all constellations, one entry per satellite
+
+    int64_t utcSeconds() const;  // seconds since 1970-01-01 UTC; meaningful when timeValid
+};
+
+// NMEA 0183 (4.10 style, as the Cap's AT6668 sends it): RMC, GGA, GSA and GSV, with the
+// constellation taken from the talker ID or GSA's system ID field. Host-tested; no hardware here.
+class NmeaParser {
+   public:
+    // Raw bytes from the UART, in any chunks.
+    void feed(const char* data, size_t len);
+    // One sentence without its line end. False if malformed or its checksum is wrong.
+    bool sentence(const std::string& line);
+
+    // Called with every complete line fed in, valid or not (`gnss nmea on` echoes them).
+    std::function<void(const std::string&)> onLine;
+
+    const GnssState& state() const { return state_; }
+    uint32_t goodSentences() const { return good_; }
+    uint32_t badSentences() const { return bad_; }
+
+   private:
+    using Fields = std::vector<std::string>;
+    void rmc(const Fields& f);
+    void gga(const Fields& f);
+    void gsa(const Fields& f, Constellation talker);
+    void gsv(const Fields& f, Constellation talker);
+    void rebuildSatellites();
+
+    static constexpr size_t kMaxLine = 120;
+    std::string line_;
+    bool overflow_ = false;
+    uint32_t good_ = 0, bad_ = 0;
+    GnssState state_;
+    // GSV sequences per (constellation, signal): pending until their last message.
+    std::map<std::pair<int, int>, std::vector<Satellite>> pending_, inView_;
+    std::map<int, std::set<int>> used_;  // per constellation, from GSA
+};
+
+}  // namespace roro::gnss

lib/gnss/src/track.cpp

@@ -0,0 +1,76 @@
+#include "track.h"
+
+#include <cmath>
+#include <cstdio>
+#include <ctime>
+
+namespace roro::gnss {
+
+namespace {
+
+constexpr double kEarthRadiusM = 6371000.0;
+
+double radians(double degrees) { return degrees * M_PI / 180.0; }
+
+// UTC fields from seconds since 1970 (gmtime_r works on the device and the PC alike).
+struct tm utc(int64_t seconds) {
+    time_t t = static_cast<time_t>(seconds);
+    struct tm out;
+    gmtime_r(&t, &out);
+    return out;
+}
+
+}  // namespace
+
+double distanceMeters(double lat1, double lon1, double lat2, double lon2) {
+    double dLat = radians(lat2 - lat1), dLon = radians(lon2 - lon1);
+    double h = std::sin(dLat / 2) * std::sin(dLat / 2) +
+               std::cos(radians(lat1)) * std::cos(radians(lat2)) * std::sin(dLon / 2) * std::sin(dLon / 2);
+    return 2 * kEarthRadiusM * std::asin(std::sqrt(h));
+}
+
+bool TrackRule::due(uint32_t nowMs, double lat, double lon) {
+    if (any_ && (nowMs - lastMs_ < kEveryMs || distanceMeters(lat_, lon_, lat, lon) < kMinMeters)) return false;
+    any_ = true;
+    lastMs_ = nowMs;
+    lat_ = lat;
+    lon_ = lon;
+    return true;
+}
+
+std::string trackPath(int64_t utcSeconds) {
+    struct tm t = utc(utcSeconds);
+    char buf[48];
+    std::snprintf(buf, sizeof buf, "/gnss/tracks/%04d%02d%02d-%02d%02d%02d.gpx", t.tm_year + 1900, t.tm_mon + 1,
+                  t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec);
+    return buf;
+}
+
+namespace gpx {
+
+std::string header(const std::string& name) {
+    return "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
+           "<gpx version=\"1.1\" creator=\"roro9stack\" xmlns=\"http://www.topografix.com/GPX/1/1\">\n"
+           "<trk><name>" + name + "</name><trkseg>";
+}
+
+std::string point(double lat, double lon, bool hasElevation, float elevationM, int64_t utcSeconds) {
+    struct tm t = utc(utcSeconds);
+    char buf[160], ele[32] = "";
+    if (hasElevation) std::snprintf(ele, sizeof ele, "<ele>%.1f</ele>", elevationM);
+    std::snprintf(buf, sizeof buf,
+                  "<trkpt lat=\"%.7f\" lon=\"%.7f\">%s<time>%04d-%02d-%02dT%02d:%02d:%02dZ</time></trkpt>", lat, lon,
+                  ele, t.tm_year + 1900, t.tm_mon + 1, t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec);
+    return buf;
+}
+
+std::string footer() { return "</trkseg></trk></gpx>"; }
+
+bool finished(const std::string& tail) {
+    size_t end = tail.find_last_not_of(" \r\n\t");
+    return end != std::string::npos && end + 1 >= 6 && tail.compare(end + 1 - 6, 6, "</gpx>") == 0;
+}
+
+}  // namespace gpx
+
+}  // namespace roro::gnss

lib/gnss/src/track.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+
+namespace roro::gnss {
+
+// Great-circle distance in metres (haversine, mean Earth radius).
+double distanceMeters(double lat1, double lon1, double lat2, double lon2);
+
+// When a Track takes its next point (Q63): the first one always, then at least every 5 s and only
+// after moving at least 5 m, so standing still doesn't fill the card.
+class TrackRule {
+   public:
+    static constexpr uint32_t kEveryMs = 5000;
+    static constexpr double kMinMeters = 5.0;
+
+    // True if this position should be recorded (and is then remembered as the last point).
+    bool due(uint32_t nowMs, double lat, double lon);
+    void reset() { any_ = false; }
+
+   private:
+    bool any_ = false;
+    uint32_t lastMs_ = 0;
+    double lat_ = 0, lon_ = 0;
+};
+
+// "/gnss/tracks/YYYYMMDD-HHMMSS.gpx", from the UTC start time (Storage Clean-up reads its date).
+std::string trackPath(int64_t utcSeconds);
+
+// GPX 1.1, written a line at a time: the header when a Track starts, a point per line, the footer
+// when it stops. A file whose footer never came (power lost) is closed at the next boot.
+namespace gpx {
+std::string header(const std::string& name);
+std::string point(double lat, double lon, bool hasElevation, float elevationM, int64_t utcSeconds);
+std::string footer();
+bool finished(const std::string& tail);  // the end of a file: does it close the GPX?
+}  // namespace gpx
+
+}  // namespace roro::gnss

lib/input/src/key_mapper.cpp

@@ -99,6 +99,20 @@ void KeyMapper::onChar(char c, const RawKeys& keys, std::vector<KeyEvent>& out)
                     return;
                 }
                 break;
+            case 'h':
+            case 'H':
+                if (keys.fn) {  // Fn+h: help, while typing too
+                    out.push_back(KeyEvent::of(Key::Help));
+                    return;
+                }
+                break;
+            case '?':
+                if (!textEntry_ && !keys.fn) {  // ? alone, when it wouldn't be typed
+                    out.push_back(KeyEvent::of(Key::Help));
+                    return;
+                }
+                if (keys.fn) return;
+                break;
             default:
                 if (keys.fn) return;  // other Fn combos are unassigned
                 break;

lib/input/src/key_mapper.h

@@ -23,7 +23,7 @@ struct RawKeys {
 
 // Turns keyboard state changes into logical KeyEvents: only newly pressed keys produce events;
 // Fn + ; . , / are arrows, and so are ; . , / alone when no text is being entered; ` is Back and
-// Fn + ` is Home; the Compose Key (opt) followed by an accent and a letter types the accented
+// Fn + ` is Home; Fn + h is Help anywhere, and so is ? when no text is being entered; the Compose Key (opt) followed by an accent and a letter types the accented
 // letter (opt ' e -> é).
 class KeyMapper {
    public:

lib/lora/src/loratap.cpp

@@ -0,0 +1,64 @@
+#include "loratap.h"
+
+#include <algorithm>
+#include <cmath>
+#include <cstdio>
+#include <ctime>
+
+namespace roro::lora {
+
+static void le16(std::vector<uint8_t>& o, uint16_t v) { o.insert(o.end(), {uint8_t(v), uint8_t(v >> 8)}); }
+static void le32(std::vector<uint8_t>& o, uint32_t v) {
+    o.insert(o.end(), {uint8_t(v), uint8_t(v >> 8), uint8_t(v >> 16), uint8_t(v >> 24)});
+}
+
+// LoRaTap's dBm encoding: -139 dBm plus the byte, clamped to what a byte holds.
+static uint8_t dbmByte(float dbm) {
+    long v = std::lround(dbm + 139);
+    return static_cast<uint8_t>(std::clamp(v, 0L, 255L));
+}
+
+std::string capturePath(int64_t utcSeconds) {
+    time_t t = static_cast<time_t>(utcSeconds);
+    struct tm u;
+    gmtime_r(&t, &u);
+    char buf[48];
+    std::snprintf(buf, sizeof buf, "/captures/lora/%04d%02d%02d-%02d%02d%02d.pcap", u.tm_year + 1900, u.tm_mon + 1,
+                  u.tm_mday, u.tm_hour, u.tm_min, u.tm_sec);
+    return buf;
+}
+
+void appendPcapHeader(std::vector<uint8_t>& out) {
+    le32(out, 0xA1B2C3D4);
+    le16(out, 2);
+    le16(out, 4);
+    le32(out, 0);      // time zone
+    le32(out, 0);      // timestamp accuracy
+    le32(out, 65535);  // snap length
+    le32(out, 270);    // LINKTYPE_LORATAP
+}
+
+void appendRecord(std::vector<uint8_t>& out, uint32_t seconds, uint32_t micros, const RxInfo& rx, const uint8_t* data,
+                  size_t len) {
+    uint32_t captured = static_cast<uint32_t>(kLoraTapSize + len);
+    le32(out, seconds);
+    le32(out, micros);
+    le32(out, captured);
+    le32(out, captured);
+
+    uint32_t f = rx.frequencyHz;
+    // The spec puts packet RSSI in quarter dB below 0 dB SNR (an SX127x formula), but Wireshark
+    // reads it as -139 dBm plus the byte either way, and the SX1262 already gives dBm.
+    uint8_t packetRssi = dbmByte(rx.rssi);
+    long snr = std::clamp(std::lround(rx.snr * 4), -128L, 127L);
+    out.insert(out.end(), {
+                              0, 0, 0, uint8_t(kLoraTapSize),  // version 0, padding, length
+                              uint8_t(f >> 24), uint8_t(f >> 16), uint8_t(f >> 8), uint8_t(f),
+                              uint8_t(std::lround(rx.bandwidthKHz / 125)), rx.spreadingFactor,
+                              packetRssi, dbmByte(rx.rssi), dbmByte(rx.noiseFloor),
+                              static_cast<uint8_t>(static_cast<int8_t>(snr)), rx.syncWord,
+                          });
+    if (len) out.insert(out.end(), data, data + len);
+}
+
+}  // namespace roro::lora

lib/lora/src/loratap.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace roro::lora {
+
+// What the radio knew about one received packet.
+struct RxInfo {
+    uint32_t frequencyHz = 0;
+    float bandwidthKHz = 0;
+    uint8_t spreadingFactor = 0;
+    float rssi = 0;        // dBm
+    float snr = 0;         // dB
+    float noiseFloor = 0;  // dBm, instantaneous RSSI just before the packet, when known
+    uint8_t syncWord = 0;
+};
+
+// A Capture file (M3, Q97): pcap with LoRaTap v0 headers (LINKTYPE_LORATAP, 270), which Wireshark
+// reads. pcap fields are little-endian, LoRaTap fields big-endian.
+void appendPcapHeader(std::vector<uint8_t>& out);
+void appendRecord(std::vector<uint8_t>& out, uint32_t seconds, uint32_t micros, const RxInfo& rx, const uint8_t* data,
+                  size_t len);
+
+// "/captures/lora/YYYYMMDD-HHMMSS.pcap" in UTC, dated like Tracks so Storage Clean-up can age it.
+std::string capturePath(int64_t utcSeconds);
+
+constexpr size_t kLoraTapSize = 15;
+constexpr size_t kRecordOverhead = 16 + kLoraTapSize;
+
+}  // namespace roro::lora

lib/lora/src/packet_view.cpp

@@ -0,0 +1,83 @@
+#include "packet_view.h"
+
+#include <cmath>
+#include <cstdio>
+
+#include "meshtastic_header.h"
+#include "meshtastic_presets.h"
+
+namespace roro::lora {
+
+using namespace meshtastic;
+
+std::string row(const PacketSummary& p, const std::string& time) {
+    char s[64];
+    int n = std::snprintf(s, sizeof s, "%s %ld %.1f ", time.c_str(), std::lround(p.rssi), p.snr);
+    std::string out(s, n);
+    PacketHeader h;
+    if (!p.crcOk) return out + "bad CRC, " + std::to_string(p.len) + " B";
+    if (!p.meshtastic || !parseHeader(p.data, p.len, h)) return out + std::to_string(p.len) + " B";
+    auto shortId = [](uint32_t node) {
+        if (node == kBroadcast) return std::string("all");
+        char id[8];
+        std::snprintf(id, sizeof id, "%04x", static_cast<unsigned>(node & 0xFFFF));
+        return std::string(id);
+    };
+    out += shortId(h.from) + ">" + shortId(h.to);
+    if (h.hopsAway() >= 0) out += " " + std::to_string(h.hopsAway()) + "/" + std::to_string(h.hopStart());
+    return out;
+}
+
+std::vector<std::string> hexDump(const uint8_t* data, size_t len) {
+    std::vector<std::string> lines;
+    for (size_t at = 0; at < len; at += 8) {
+        char s[48];
+        int n = std::snprintf(s, sizeof s, "%04x", static_cast<unsigned>(at));
+        std::string text;
+        for (size_t i = 0; i < 8; ++i) {
+            if (at + i < len) {
+                n += std::snprintf(s + n, sizeof s - n, " %02x", data[at + i]);
+                uint8_t b = data[at + i];
+                text += b >= 0x20 && b < 0x7F ? static_cast<char>(b) : '.';
+            } else {
+                n += std::snprintf(s + n, sizeof s - n, "   ");
+            }
+        }
+        lines.push_back(std::string(s, n) + " " + text);
+    }
+    return lines;
+}
+
+std::vector<std::string> headerLines(const uint8_t* data, size_t len) {
+    PacketHeader h;
+    if (!parseHeader(data, len, h)) return {};
+    char s[64];
+    std::vector<std::string> lines;
+    lines.push_back("From " + nodeId(h.from) + " to " + nodeId(h.to));
+    std::snprintf(s, sizeof s, "Packet %08x%s%s", static_cast<unsigned>(h.id), h.wantAck() ? ", wants an ack" : "",
+                  h.viaMqtt() ? ", via MQTT" : "");
+    lines.push_back(s);
+    if (h.hopsAway() >= 0)
+        std::snprintf(s, sizeof s, "Hops %d of %u, limit %u left", h.hopsAway(), h.hopStart(), h.hopLimit());
+    else
+        std::snprintf(s, sizeof s, "Hop limit %u left (old firmware)", h.hopLimit());
+    lines.push_back(s);
+    // Which preset's default Channel (named after it, with the public key) has this hash.
+    std::string channel;
+    for (size_t i = 0; i < kEu868PresetCount && channel.empty(); ++i)
+        if (channelHash(kEu868Presets[i].name, kDefaultKey, sizeof kDefaultKey) == h.channelHash)
+            channel = std::string(" (") + kEu868Presets[i].name + ", default key)";
+    std::snprintf(s, sizeof s, "Channel 0x%02x%s", h.channelHash, channel.c_str());
+    lines.push_back(s);
+    if (h.relayNode) {
+        std::snprintf(s, sizeof s, "Relayed by ..%02x", h.relayNode);
+        lines.push_back(s);
+    }
+    if (h.nextHop) {
+        std::snprintf(s, sizeof s, "Next hop ..%02x", h.nextHop);
+        lines.push_back(s);
+    }
+    return lines;
+}
+
+}  // namespace roro::lora

lib/lora/src/packet_view.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace roro::lora {
+
+// What the LoRa Scanner shows of one packet (M3, Q96).
+struct PacketSummary {
+    const uint8_t* data;
+    size_t len;
+    float rssi, snr;
+    bool crcOk;
+    bool meshtastic;  // received on Meshtastic settings (sync word 0x2B): read its clear header
+};
+
+// One list row, at most about 36 characters: "21:45:07 -97 6.2 5678>all 1/3". Nodes by their default
+// short name (the last 4 hex digits); headerLines() has the full numbers.
+std::string row(const PacketSummary& p, const std::string& time);
+
+// Eight bytes a line, with the printable ones: "0000 ff ff ff ff 78 56 34 12 ....xV4.".
+std::vector<std::string> hexDump(const uint8_t* data, size_t len);
+
+// The Meshtastic header, one field a line; empty when the packet is too short to have one.
+std::vector<std::string> headerLines(const uint8_t* data, size_t len);
+
+}  // namespace roro::lora

lib/lora/src/sweep_view.cpp

@@ -0,0 +1,48 @@
+#include "sweep_view.h"
+
+#include <algorithm>
+
+namespace roro::lora {
+
+namespace {
+constexpr int kPeakAboveFloorDb = 10;
+constexpr size_t kMaxPeaks = 3;
+}  // namespace
+
+SweepStats summarize(const int8_t* dbm, size_t steps, uint32_t fromHz, uint32_t stepHz) {
+    SweepStats s;
+    if (!steps) return s;
+    std::vector<int8_t> sorted(dbm, dbm + steps);
+    std::nth_element(sorted.begin(), sorted.begin() + steps / 2, sorted.end());
+    s.floor = sorted[steps / 2];
+    s.top = *std::max_element(dbm, dbm + steps);
+    for (size_t i = 0; i < steps; ++i) {
+        int v = dbm[i];
+        bool localMax = (i == 0 || v >= dbm[i - 1]) && (i + 1 == steps || v > dbm[i + 1]);
+        if (localMax && v >= s.floor + kPeakAboveFloorDb) s.peaks.push_back({fromHz + static_cast<uint32_t>(i) * stepHz, v});
+    }
+    std::stable_sort(s.peaks.begin(), s.peaks.end(), [](const SweepPeak& a, const SweepPeak& b) { return a.dbm > b.dbm; });
+    if (s.peaks.size() > kMaxPeaks) s.peaks.resize(kMaxPeaks);
+    return s;
+}
+
+uint8_t heatLevel(int dbm, int low, int high) {
+    if (dbm <= low) return 0;
+    if (dbm >= high) return 255;
+    return static_cast<uint8_t>((dbm - low) * 255 / (high - low) + ((dbm - low) * 255 % (high - low) ? 1 : 0));
+}
+
+uint16_t heatColor(uint8_t level) {
+    // Five segments of 51 steps each.
+    auto rgb = [](int r, int g, int b) { return static_cast<uint16_t>((r >> 3) << 11 | (g >> 2) << 5 | (b >> 3)); };
+    int seg = std::min(level / 51, 4), t = (level - seg * 51) * 255 / 51;
+    switch (seg) {
+        case 0: return rgb(0, 0, t);              // black to blue
+        case 1: return rgb(0, t, 255);            // blue to cyan
+        case 2: return rgb(0, 255, 255 - t);      // cyan to green
+        case 3: return rgb(t, 255, 0);            // green to yellow
+        default: return rgb(255, 255 - t, 0);     // yellow to red
+    }
+}
+
+}  // namespace roro::lora

lib/lora/src/sweep_view.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <vector>
+
+namespace roro::lora {
+
+// What a Sweep pass says about the band (M3, Q98): one RSSI reading (dBm) per step.
+struct SweepPeak {
+    uint32_t hz;
+    int dbm;
+};
+struct SweepStats {
+    int floor = 0;  // the median: the band's noise floor, whatever a few signals do
+    int top = 0;    // the strongest reading
+    std::vector<SweepPeak> peaks;  // at most 3, strongest first, each a local maximum >= 10 dB above the floor
+};
+
+SweepStats summarize(const int8_t* dbm, size_t steps, uint32_t fromHz, uint32_t stepHz);
+
+// The waterfall's colours: a reading between `low` and `high` dBm as 0..255, then RGB565 along
+// black, blue, cyan, green, yellow, red.
+uint8_t heatLevel(int dbm, int low, int high);
+uint16_t heatColor(uint8_t level);
+
+}  // namespace roro::lora

lib/meshtastic/src/meshtastic_header.cpp

@@ -0,0 +1,28 @@
+#include "meshtastic_header.h"
+
+#include <cstdio>
+
+namespace roro::meshtastic {
+
+static uint32_t le32(const uint8_t* p) { return p[0] | p[1] << 8 | p[2] << 16 | static_cast<uint32_t>(p[3]) << 24; }
+
+bool parseHeader(const uint8_t* data, size_t len, PacketHeader& out) {
+    if (!data || len < kHeaderSize) return false;
+    out.to = le32(data);
+    out.from = le32(data + 4);
+    out.id = le32(data + 8);
+    out.flags = data[12];
+    out.channelHash = data[13];
+    out.nextHop = data[14];
+    out.relayNode = data[15];
+    return true;
+}
+
+std::string nodeId(uint32_t node) {
+    if (node == kBroadcast) return "all";
+    char s[10];
+    std::snprintf(s, sizeof s, "!%08x", static_cast<unsigned>(node));
+    return s;
+}
+
+}  // namespace roro::meshtastic

lib/meshtastic/src/meshtastic_header.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+
+namespace roro::meshtastic {
+
+constexpr uint32_t kBroadcast = 0xFFFFFFFF;
+
+// The 16 bytes every Meshtastic packet starts with, sent in clear (little-endian). The payload
+// after it is encrypted with the Channel's key.
+struct PacketHeader {
+    uint32_t to = 0, from = 0, id = 0;
+    uint8_t flags = 0;
+    uint8_t channelHash = 0;  // the Channel's name and key folded into a byte (see channelHash())
+    uint8_t nextHop = 0;      // last byte of the Node meant to relay it next; 0 when flooding
+    uint8_t relayNode = 0;    // last byte of the Node that relayed it to us
+
+    uint8_t hopLimit() const { return flags & 0x07; }
+    bool wantAck() const { return flags & 0x08; }
+    bool viaMqtt() const { return flags & 0x10; }
+    uint8_t hopStart() const { return flags >> 5; }
+    bool broadcast() const { return to == kBroadcast; }
+    // How many times it was relayed before we heard it; -1 when the sender didn't say (hop start 0).
+    int hopsAway() const { return hopStart() == 0 ? -1 : hopStart() - hopLimit(); }
+};
+
+constexpr size_t kHeaderSize = 16;
+
+bool parseHeader(const uint8_t* data, size_t len, PacketHeader& out);
+
+// "!12345678", as Meshtastic writes node numbers; "all" for broadcast.
+std::string nodeId(uint32_t node);
+
+}  // namespace roro::meshtastic

lib/meshtastic/src/meshtastic_presets.cpp

@@ -0,0 +1,47 @@
+#include "meshtastic_presets.h"
+
+#include <cmath>
+#include <cstring>
+
+namespace roro::meshtastic {
+
+const uint8_t kDefaultKey[16] = {0xd4, 0xf1, 0xbb, 0x3a, 0x20, 0x29, 0x07, 0x59,
+                                 0xf0, 0xbc, 0xff, 0xab, 0xcf, 0x4e, 0x69, 0x01};
+
+// firmware src/mesh/MeshRadio.h (modemPresetToParams) and RadioInterface.cpp (PRESETS_EU_868).
+const Preset kEu868Presets[] = {
+    {"LongFast", 250, 11, 5},  {"LongSlow", 125, 12, 8},  {"MediumSlow", 250, 10, 5}, {"MediumFast", 250, 9, 5},
+    {"ShortSlow", 250, 8, 5},  {"ShortFast", 250, 7, 5},  {"LongMod", 125, 11, 8},
+};
+const size_t kEu868PresetCount = sizeof kEu868Presets / sizeof kEu868Presets[0];
+
+const Preset* findPreset(const char* name) {
+    for (const Preset& p : kEu868Presets)
+        if (std::strcmp(p.name, name) == 0) return &p;
+    return nullptr;
+}
+
+uint32_t djb2(const char* s) {
+    uint32_t h = 5381;
+    for (; *s; ++s) h = (h << 5) + h + static_cast<unsigned char>(*s);
+    return h;
+}
+
+uint8_t channelHash(const char* name, const uint8_t* key, size_t keyLen) {
+    uint8_t h = 0;
+    for (; *name; ++name) h ^= static_cast<uint8_t>(*name);
+    for (size_t i = 0; i < keyLen; ++i) h ^= key[i];
+    return h;
+}
+
+uint32_t eu868FrequencyHz(const Preset& preset, const char* channelName) {
+    constexpr double kStartMHz = 869.4, kEndMHz = 869.65;
+    double slotMHz = preset.bwKHz / 1000.0;
+    uint32_t slots = static_cast<uint32_t>(std::lround((kEndMHz - kStartMHz) / slotMHz));
+    const char* name = channelName && *channelName ? channelName : preset.name;
+    uint32_t slot = slots ? djb2(name) % slots : 0;
+    double mhz = kStartMHz + slotMHz / 2 + slot * slotMHz;
+    return static_cast<uint32_t>(std::lround(mhz * 1e6));
+}
+
+}  // namespace roro::meshtastic

lib/meshtastic/src/meshtastic_presets.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+
+namespace roro::meshtastic {
+
+// Radio settings shared by every Meshtastic preset (firmware src/mesh/RadioInterface.h).
+constexpr uint8_t kSyncWord = 0x2B;
+constexpr uint16_t kPreambleLength = 16;
+
+// The default Channel key ("AQ==", expanded): public, so the default Channel is readable by anyone.
+extern const uint8_t kDefaultKey[16];
+
+// A modem preset: bandwidth, spreading factor and coding rate (4/cr). Named as Meshtastic shows them.
+struct Preset {
+    const char* name;
+    float bwKHz;
+    uint8_t sf;
+    uint8_t cr;
+};
+
+// The presets Meshtastic allows in EU_868, its order, LongFast (the default) first.
+extern const Preset kEu868Presets[];
+extern const size_t kEu868PresetCount;
+const Preset* findPreset(const char* name);  // nullptr when EU_868 doesn't allow it
+
+// djb2, as Meshtastic hashes a Channel's name to pick a frequency slot.
+uint32_t djb2(const char* s);
+
+// The byte in every packet header naming its Channel: the name's bytes XORed with the key's.
+uint8_t channelHash(const char* name, const uint8_t* key, size_t keyLen);
+
+// EU_868 is 869.4 to 869.65 MHz: the slot comes from the Channel's name (the preset's name for
+// an unnamed Channel, which is the default).
+uint32_t eu868FrequencyHz(const Preset& preset, const char* channelName = nullptr);
+
+}  // namespace roro::meshtastic

lib/net/src/ipv4.cpp

@@ -0,0 +1,97 @@
+#include "ipv4.h"
+
+#include <cstdio>
+
+namespace roro::net {
+
+bool parseIpv4(const std::string& text, uint32_t& out) {
+    uint32_t value = 0;
+    int parts = 0, digits = 0, part = 0;
+    for (char c : text) {
+        if (c >= '0' && c <= '9') {
+            if (++digits > 3) return false;
+            part = part * 10 + (c - '0');
+            if (part > 255) return false;
+        } else if (c == '.') {
+            if (digits == 0 || ++parts > 3) return false;
+            value = value << 8 | part;
+            part = digits = 0;
+        } else {
+            return false;
+        }
+    }
+    if (digits == 0 || parts != 3) return false;
+    out = value << 8 | part;
+    return true;
+}
+
+std::string formatIpv4(uint32_t a) {
+    char s[16];
+    std::snprintf(s, sizeof s, "%u.%u.%u.%u", static_cast<unsigned>(a >> 24), static_cast<unsigned>(a >> 16 & 255),
+                  static_cast<unsigned>(a >> 8 & 255), static_cast<unsigned>(a & 255));
+    return s;
+}
+
+uint32_t maskOf(int prefix) { return prefix <= 0 ? 0 : prefix >= 32 ? 0xFFFFFFFFu : ~0u << (32 - prefix); }
+
+std::string checkFixed(const FixedIp& f) {
+    if (f.prefix < 1 || f.prefix > 30) return "The prefix must be 1 to 30";
+    if (f.address == 0) return "0.0.0.0 isn't an address a device can have";
+    uint32_t mask = maskOf(f.prefix), network = f.address & mask, broadcast = network | ~mask;
+    if (f.address == network) return formatIpv4(f.address) + " is the network's own address";
+    if (f.address == broadcast) return formatIpv4(f.address) + " is the broadcast address";
+    if (f.gateway == 0) return "";
+    if (f.gateway == f.address) return "The gateway can't be this device's address";
+    if ((f.gateway & mask) != network)
+        return "The gateway " + formatIpv4(f.gateway) + " isn't in " + formatIpv4(network) + "/" + std::to_string(f.prefix);
+    if (f.gateway == broadcast) return "The gateway " + formatIpv4(f.gateway) + " is the broadcast address";
+    if (f.gateway == network) return "The gateway " + formatIpv4(f.gateway) + " is the network's own address";
+    return "";
+}
+
+std::string parseFixed(const std::string& text, FixedIp& out) {
+    size_t slash = text.find('/');
+    if (slash == std::string::npos) return "Write it as address/prefix, then the gateway if there is one";
+    size_t space = text.find(' ', slash);
+    std::string address = text.substr(0, slash);
+    std::string prefix = text.substr(slash + 1, space == std::string::npos ? std::string::npos : space - slash - 1);
+    std::string gateway = space == std::string::npos ? "" : text.substr(space + 1);
+    FixedIp f;
+    if (!parseIpv4(address, f.address)) return address + " isn't an IPv4 address";
+    int p = 0;
+    if (prefix.empty() || prefix.size() > 2) return "The prefix must be 1 to 30";
+    for (char c : prefix) {
+        if (c < '0' || c > '9') return "The prefix must be 1 to 30";
+        p = p * 10 + (c - '0');
+    }
+    f.prefix = static_cast<uint8_t>(p);
+    if (!gateway.empty() && !parseIpv4(gateway, f.gateway)) return gateway + " isn't an IPv4 address";
+    std::string why = checkFixed(f);
+    if (why.empty()) out = f;
+    return why;
+}
+
+std::string formatFixed(const FixedIp& f) {
+    std::string s = formatIpv4(f.address) + "/" + std::to_string(f.prefix);
+    if (f.gateway) s += " " + formatIpv4(f.gateway);
+    return s;
+}
+
+bool validHost(const std::string& text) {
+    if (text.empty() || text.size() > 63) return false;
+    uint32_t ignored;
+    if (parseIpv4(text, ignored)) return true;
+    bool allNumeric = true;  // digits and dots only, but not an address: "1.2.3", "999.1.1.1"
+    char previous = '.';
+    for (char c : text) {
+        bool letter = (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'), digit = c >= '0' && c <= '9';
+        if (!letter && !digit && c != '-' && c != '.') return false;
+        if (c == '.' && (previous == '.' || previous == '-')) return false;  // empty label, or one ending in '-'
+        if (c == '-' && previous == '.') return false;                       // a label starting with '-'
+        if (letter || c == '-') allNumeric = false;
+        previous = c;
+    }
+    return previous != '.' && previous != '-' && !allNumeric;
+}
+
+}  // namespace roro::net

lib/net/src/ipv4.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+
+namespace roro::net {
+
+// IPv4 addresses as 32-bit numbers, most significant byte first: 10.39.39.12 is 0x0A27270C.
+bool parseIpv4(const std::string& text, uint32_t& out);  // strict: four decimal numbers, 0 to 255
+std::string formatIpv4(uint32_t address);
+uint32_t maskOf(int prefix);  // 24 -> 255.255.255.0
+
+// A Saved Network's Fixed setting (S1, Q105 to Q107). gateway 0: none.
+struct FixedIp {
+    uint32_t address = 0;
+    uint8_t prefix = 24;
+    uint32_t gateway = 0;
+};
+
+// "" when a device can use it, otherwise why not, for a human (Q111).
+std::string checkFixed(const FixedIp& f);
+
+// "address/prefix [gateway]", as typed on the console and kept in flash. parseFixed() also checks.
+std::string parseFixed(const std::string& text, FixedIp& out);
+std::string formatFixed(const FixedIp& f);
+
+// An IPv4 address or a host name, as an NTP server may be (Q110).
+bool validHost(const std::string& text);
+
+}  // namespace roro::net

lib/net/src/traffic.cpp

@@ -0,0 +1,46 @@
+#include "traffic.h"
+
+#include <atomic>
+#include <cstdio>
+
+namespace roro::net {
+
+namespace {
+constexpr size_t kUsers = static_cast<size_t>(User::Count);
+std::atomic<uint32_t> in_[kUsers], out_[kUsers];
+}  // namespace
+
+const char* userName(User user) {
+    switch (user) {
+        case User::Irc: return "IRC";
+        case User::Gemini: return "Gemini";
+        case User::DebugConsole: return "Debug Console";
+        case User::Updates: return "Updates";
+        default: return "?";
+    }
+}
+
+void received(User user, size_t bytes) { in_[static_cast<size_t>(user)] += static_cast<uint32_t>(bytes); }
+void sent(User user, size_t bytes) { out_[static_cast<size_t>(user)] += static_cast<uint32_t>(bytes); }
+Traffic traffic(User user) { return {in_[static_cast<size_t>(user)], out_[static_cast<size_t>(user)]}; }
+
+void resetTraffic() {
+    for (size_t i = 0; i < kUsers; i++) in_[i] = out_[i] = 0;
+}
+
+uint32_t bytesPerSecond(uint32_t before, uint32_t now, uint32_t elapsedMs) {
+    if (!elapsedMs) return 0;
+    return static_cast<uint32_t>(static_cast<uint64_t>(now - before) * 1000 / elapsedMs);  // wraps with the counter
+}
+
+std::string formatTraffic(uint32_t bytes) {
+    char s[16];
+    if (bytes < 1000) std::snprintf(s, sizeof s, "%u B", static_cast<unsigned>(bytes));
+    else if (bytes < 10 * 1024) std::snprintf(s, sizeof s, "%.1f KB", bytes / 1024.0);
+    else if (bytes < 1000 * 1024) std::snprintf(s, sizeof s, "%u KB", static_cast<unsigned>(bytes / 1024));
+    else if (bytes < 10u * 1024 * 1024) std::snprintf(s, sizeof s, "%.1f MB", bytes / 1048576.0);
+    else std::snprintf(s, sizeof s, "%u MB", static_cast<unsigned>(bytes / 1048576));
+    return s;
+}
+
+}  // namespace roro::net

lib/net/src/traffic.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+
+namespace roro::net {
+
+// Bytes each network service has read and written since boot (S1, Q121), as the service sees
+// them: for TLS connections that's the plain text, without the handshake or record overhead.
+// Counted from the services' own tasks, read from the main loop.
+enum class User : uint8_t { Irc, Gemini, DebugConsole, Updates, Count };
+const char* userName(User user);
+
+struct Traffic {
+    uint32_t in = 0, out = 0;
+};
+void received(User user, size_t bytes);
+void sent(User user, size_t bytes);
+Traffic traffic(User user);
+void resetTraffic();  // for tests
+
+uint32_t bytesPerSecond(uint32_t before, uint32_t now, uint32_t elapsedMs);
+std::string formatTraffic(uint32_t bytes);  // "999 B", "1.5 KB", "12 KB", "1.7 MB"
+
+}  // namespace roro::net

lib/notes/src/note_text.cpp

@@ -0,0 +1,329 @@
+#include "note_text.h"
+
+#include <algorithm>
+
+namespace roro::notes {
+
+namespace {
+bool continuation(char c) { return (static_cast<uint8_t>(c) & 0xC0) == 0x80; }
+}  // namespace
+
+NoteText::NoteText(int cols, int rows) : cols_(std::max(1, cols)), rows_(std::max(1, rows)) { text_.reserve(kMaxBytes); }
+
+NoteText::NoteText(int cols, int rows, std::string&& text) : cols_(std::max(1, cols)), rows_(std::max(1, rows)), text_(std::move(text)) {
+    dropCarriageReturns();
+    if (text_.size() > kMaxBytes) text_.resize(kMaxBytes);  // the caller checks sizes: not reached
+    text_.reserve(kMaxBytes);
+}
+
+void NoteText::dropCarriageReturns() {
+    size_t kept = 0;
+    for (size_t i = 0; i < text_.size(); i++)
+        if (!(text_[i] == '\r' && i + 1 < text_.size() && text_[i + 1] == '\n')) text_[kept++] = text_[i];
+    text_.resize(kept);
+}
+
+bool NoteText::setText(const std::string& text) {
+    size_t kept = text.size();
+    for (size_t i = 0; i + 1 < text.size(); i++)
+        if (text[i] == '\r' && text[i + 1] == '\n') kept--;
+    if (kept > kMaxBytes) return false;
+    text_.assign(text);
+    dropCarriageReturns();
+    cursor_ = top_ = 0;
+    goal_ = -1;
+    revision_++;
+    return true;
+}
+
+size_t NoteText::nextLine(size_t start) const {
+    size_t size = text_.size();
+    int count = 0;
+    size_t lastSpace = 0;
+    bool space = false;
+    for (size_t i = start; i < size; i++) {
+        char c = text_[i];
+        if (c == '\n') return i + 1;
+        if (continuation(c)) continue;
+        if (count == cols_) {  // one character too many: wrap
+            if (c == ' ') return i + 1;       // the space stays at the end of this line
+            if (space) return lastSpace + 1;  // after the last space that fits
+            return i;                         // a word longer than the screen is cut
+        }
+        count++;
+        if (c == ' ') {
+            lastSpace = i;
+            space = true;
+        }
+    }
+    return size;
+}
+
+size_t NoteText::lineOf(size_t pos) const {
+    size_t size = text_.size();
+    pos = std::min(pos, size);
+    size_t a = pos;  // the start of the paragraph: after the newline before `pos`
+    while (a > 0 && text_[a - 1] != '\n') a--;
+    while (a < size) {
+        size_t n = nextLine(a);
+        if (n > pos) return a;
+        // The end of the text is on the last line, unless that line ended with a newline: then
+        // it's on an empty line of its own.
+        if (n == size && pos == size && text_[size - 1] != '\n') return a;
+        a = n;
+    }
+    return a;
+}
+
+bool NoteText::hasLineAfter(size_t start) const {
+    size_t n = nextLine(start), size = text_.size();
+    if (n < size) return true;
+    return start < size && lineOf(size) != start;  // the empty line after a final newline
+}
+
+size_t NoteText::lastSpot(size_t start) const {
+    size_t n = nextLine(start), size = text_.size();
+    if (n == start) return start;  // the empty line at the end
+    if (n == size && lineOf(size) == start) return size;
+    size_t p = n - 1;  // before the newline, the space or the last character the line ends with
+    while (p > start && continuation(text_[p])) p--;
+    return p;
+}
+
+int NoteText::columnOf(size_t start, size_t pos) const {
+    int col = 0;
+    for (size_t i = start; i < pos && i < text_.size(); i++)
+        if (!continuation(text_[i])) col++;
+    return col;
+}
+
+size_t NoteText::atColumn(size_t start, int col) const {
+    size_t last = lastSpot(start), p = start;
+    while (p < last && col > 0) {
+        p++;
+        while (p < last && continuation(text_[p])) p++;
+        col--;
+    }
+    return p;
+}
+
+void NoteText::moved(bool keepGoal) {
+    if (!keepGoal) goal_ = -1;
+}
+
+bool NoteText::insertText(const std::string& s) {
+    if (text_.size() + s.size() > kMaxBytes) return false;
+    text_.insert(cursor_, s);
+    cursor_ += s.size();
+    revision_++;
+    moved();
+    return true;
+}
+
+bool NoteText::insert(uint32_t cp) {
+    std::string s;
+    if (cp < 0x80) s += static_cast<char>(cp);
+    else if (cp < 0x800) {
+        s += static_cast<char>(0xC0 | (cp >> 6));
+        s += static_cast<char>(0x80 | (cp & 0x3F));
+    } else if (cp < 0x10000) {
+        s += static_cast<char>(0xE0 | (cp >> 12));
+        s += static_cast<char>(0x80 | ((cp >> 6) & 0x3F));
+        s += static_cast<char>(0x80 | (cp & 0x3F));
+    } else {
+        s += static_cast<char>(0xF0 | (cp >> 18));
+        s += static_cast<char>(0x80 | ((cp >> 12) & 0x3F));
+        s += static_cast<char>(0x80 | ((cp >> 6) & 0x3F));
+        s += static_cast<char>(0x80 | (cp & 0x3F));
+    }
+    return insertText(s);
+}
+
+void NoteText::backspace() {
+    if (cursor_ == 0) return;
+    size_t from = cursor_ - 1;
+    while (from > 0 && continuation(text_[from])) from--;
+    text_.erase(from, cursor_ - from);
+    cursor_ = from;
+    revision_++;
+    moved();
+}
+
+void NoteText::left() {
+    if (cursor_ == 0) return;
+    cursor_--;
+    while (cursor_ > 0 && continuation(text_[cursor_])) cursor_--;
+    moved();
+}
+
+void NoteText::right() {
+    if (cursor_ >= text_.size()) return;
+    cursor_++;
+    while (cursor_ < text_.size() && continuation(text_[cursor_])) cursor_++;
+    moved();
+}
+
+void NoteText::up() {
+    size_t line = lineOf(cursor_);
+    if (goal_ < 0) goal_ = columnOf(line, cursor_);
+    if (line == 0) return;
+    cursor_ = atColumn(lineOf(line - 1), goal_);
+    moved(true);
+}
+
+void NoteText::down() {
+    size_t line = lineOf(cursor_);
+    if (goal_ < 0) goal_ = columnOf(line, cursor_);
+    if (!hasLineAfter(line)) return;
+    size_t next = nextLine(line);
+    cursor_ = next >= text_.size() ? text_.size() : atColumn(next, goal_);
+    moved(true);
+}
+
+void NoteText::pageUp() {
+    for (int i = 1; i < rows_; i++) up();
+}
+
+void NoteText::pageDown() {
+    for (int i = 1; i < rows_; i++) down();
+}
+
+void NoteText::lineStart() {
+    cursor_ = lineOf(cursor_);
+    moved();
+}
+
+void NoteText::lineEnd() {
+    cursor_ = lastSpot(lineOf(cursor_));
+    moved();
+}
+
+void NoteText::toStart() {
+    cursor_ = 0;
+    moved();
+}
+
+void NoteText::toEnd() {
+    cursor_ = text_.size();
+    moved();
+}
+
+void NoteText::follow() {
+    size_t line = lineOf(cursor_);
+    top_ = lineOf(std::min(top_, text_.size()));  // an edit above may have moved where lines start
+    if (line < top_) {
+        top_ = line;
+        return;
+    }
+    size_t a = top_;
+    for (int i = 0; i < rows_; i++) {
+        if (a == line) return;  // on screen
+        if (!hasLineAfter(a)) return;
+        a = nextLine(a);
+    }
+    // Below the screen: the cursor's line becomes the last row.
+    top_ = line;
+    for (int i = 1; i < rows_ && top_ > 0; i++) top_ = lineOf(top_ - 1);
+}
+
+std::vector<std::string> NoteText::rows() {
+    follow();
+    std::vector<std::string> out;
+    size_t a = top_, size = text_.size();
+    for (int i = 0; i < rows_; i++) {
+        size_t n = nextLine(a);
+        std::string row = text_.substr(a, n - a);
+        if (!row.empty() && row.back() == '\n') row.pop_back();
+        for (char& c : row)
+            if (c == '\t') c = ' ';
+        out.push_back(std::move(row));
+        if (!hasLineAfter(a)) break;
+        a = n >= size ? size : n;
+    }
+    return out;
+}
+
+int NoteText::cursorRow() {
+    follow();
+    size_t line = lineOf(cursor_), a = top_;
+    for (int i = 0; i < rows_; i++) {
+        if (a == line) return i;
+        a = nextLine(a);
+    }
+    return rows_ - 1;
+}
+
+int NoteText::cursorCol() { return columnOf(lineOf(cursor_), cursor_); }
+
+// At most a screen's worth of it: a note that is one line of 16 KB must not be copied whole.
+std::string NoteText::firstLine() const { return text_.substr(0, std::min<size_t>(text_.find('\n'), 160)); }
+
+namespace {
+// U+00C0 to U+00FF as the plain letters a file name gets; 0: left out.
+const char kPlain[64] = {
+    'a', 'a', 'a', 'a', 'a', 'a', 0,   'c', 'e', 'e', 'e', 'e', 'i', 'i', 'i', 'i',   // À..Ï
+    0,   'n', 'o', 'o', 'o', 'o', 'o', 0,   'o', 'u', 'u', 'u', 'u', 'y', 0,   's',   // Ð..ß
+    'a', 'a', 'a', 'a', 'a', 'a', 0,   'c', 'e', 'e', 'e', 'e', 'i', 'i', 'i', 'i',   // à..ï
+    0,   'n', 'o', 'o', 'o', 'o', 'o', 0,   'o', 'u', 'u', 'u', 'u', 'y', 0,   'y'};  // ð..ÿ
+
+// Drops a character the end of the string cuts in two.
+void dropPartial(std::string& s) {
+    size_t k = s.size();
+    while (k > 0 && continuation(s[k - 1]) && s.size() - k < 3) k--;
+    if (k == 0) return;
+    uint8_t lead = static_cast<uint8_t>(s[k - 1]);
+    size_t want = lead >= 0xF0 ? 4 : lead >= 0xE0 ? 3 : lead >= 0xC0 ? 2 : 1;
+    if (s.size() - (k - 1) < want) s.resize(k - 1);
+}
+}  // namespace
+
+std::string nameFromFirstLine(const std::string& firstLine, const std::string& stamp) {
+    std::string out;
+    bool dash = false;
+    for (size_t i = 0; i < firstLine.size() && out.size() < 32; i++) {
+        uint8_t c = static_cast<uint8_t>(firstLine[i]);
+        char letter = 0;
+        if (c < 0x80) {
+            if (c >= 'A' && c <= 'Z') letter = static_cast<char>(c + 32);
+            else if ((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9')) letter = static_cast<char>(c);
+        } else if (c == 0xC3 && i + 1 < firstLine.size()) {  // U+00C0..U+00FF
+            letter = kPlain[static_cast<uint8_t>(firstLine[++i]) & 0x3F];
+        } else {
+            while (i + 1 < firstLine.size() && continuation(firstLine[i + 1])) i++;  // anything else is left out
+        }
+        if (letter) {
+            if (dash && !out.empty()) out += '-';
+            dash = false;
+            out += letter;
+        } else {
+            dash = true;
+        }
+    }
+    return out.empty() ? "note-" + stamp : out;
+}
+
+std::string titleFrom(const std::string& head, size_t maxChars) {
+    for (size_t at = 0; at < head.size();) {
+        size_t end = head.find('\n', at);
+        bool cut = end == std::string::npos;  // the line goes on past what was read
+        if (cut) end = head.size();
+        std::string line = head.substr(at, end - at);
+        if (cut) dropPartial(line);
+        while (!line.empty() && (line.back() == '\r' || line.back() == ' ' || line.back() == '\t')) line.pop_back();
+        size_t first = line.find_first_not_of(" \t");
+        if (first != std::string::npos) {
+            line.erase(0, first);
+            size_t bytes = 0;
+            for (size_t chars = 0; bytes < line.size() && chars < maxChars; chars++) {
+                bytes++;
+                while (bytes < line.size() && continuation(line[bytes])) bytes++;
+            }
+            line.resize(bytes);
+            return line;
+        }
+        at = end + 1;
+    }
+    return "";
+}
+
+}  // namespace roro::notes

lib/notes/src/note_text.h

@@ -0,0 +1,81 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace roro::notes {
+
+// The text of a note while it's edited (F1, Q144, Q145): UTF-8 held whole in memory, a cursor, and
+// the part of it on screen. Lines wrap at spaces, `cols` characters wide; a line owns the space or
+// the newline it ends with, so every byte of the text belongs to exactly one line. No index of
+// lines is kept (a note of newlines alone would need twice its size): where a line starts is
+// worked out from the start of its paragraph, which is never far.
+class NoteText {
+   public:
+    static constexpr size_t kMaxBytes = 16 * 1024;
+
+    // Room for a full note is reserved once, so typing never has to find a bigger block of memory:
+    // on the device a failed allocation is the end. The second form takes over a string the
+    // caller filled (and reserved): a note is never in memory twice.
+    NoteText(int cols, int rows);
+    NoteText(int cols, int rows, std::string&& text);
+
+    // Copied into the buffer already held. CRLF becomes LF (Q148). False, and nothing changes, if
+    // it's over kMaxBytes.
+    bool setText(const std::string& text);
+    const std::string& text() const { return text_; }
+    size_t cursor() const { return cursor_; }
+    uint32_t revision() const { return revision_; }  // changes with every edit: is it saved?
+
+    bool insert(uint32_t codePoint);         // false: the note is full
+    bool insertText(const std::string& s);   // all of it or nothing
+    void backspace();
+    void left();
+    void right();
+    void up();
+    void down();
+    void pageUp();
+    void pageDown();
+    void lineStart();
+    void lineEnd();
+    void toStart();
+    void toEnd();
+
+    // The screen, kept around the cursor: its rows (tabs as spaces, the ending newline left out),
+    // and where the cursor is on it, in rows and characters.
+    std::vector<std::string> rows();
+    int cursorRow();
+    int cursorCol();
+    int percent() const { return text_.empty() ? 0 : static_cast<int>(top_ * 100 / text_.size()); }
+
+    std::string firstLine() const;  // without its newline, for the title and the file's name
+
+   private:
+    size_t nextLine(size_t start) const;       // where the line after the one at `start` starts
+    size_t lineOf(size_t pos) const;           // the start of the line `pos` is on
+    size_t lastSpot(size_t start) const;       // the last place the cursor can be on that line
+    size_t atColumn(size_t start, int col) const;
+    int columnOf(size_t start, size_t pos) const;
+    bool hasLineAfter(size_t start) const;
+    void moved(bool keepGoal = false);
+    void follow();  // scrolls so the cursor is on screen
+    void dropCarriageReturns();
+
+    int cols_, rows_;
+    std::string text_;
+    size_t cursor_ = 0, top_ = 0;
+    int goal_ = -1;  // the column Up and Down aim for, across short lines
+    uint32_t revision_ = 0;
+};
+
+// The file a new note is saved as (Q142): from its first line, "Shopping list!" -> "shopping-list",
+// or "note-<stamp>" when that gives nothing. No extension, no folder.
+std::string nameFromFirstLine(const std::string& firstLine, const std::string& stamp);
+
+// A row's title in the Notes list, from the first bytes of a file: its first line that isn't
+// blank, cut to `maxChars`; "" if there's none.
+std::string titleFrom(const std::string& head, size_t maxChars);
+
+}  // namespace roro::notes

lib/ota/src/file_receiver.cpp

@@ -94,6 +94,11 @@ void FileReceiver::chunkWritten(bool ok, uint32_t nowMs) {
     state_ = received_ == size_ ? State::Finishing : State::Receiving;
 }
 
+void FileReceiver::cardChecked(const uint8_t digest[32]) {
+    if (state_ != State::Finishing) return;
+    if (std::memcmp(digest, expected_, sizeof expected_) != 0) fail("the copy on the card differs");
+}
+
 void FileReceiver::finished(bool ok) {
     if (state_ != State::Finishing) return;
     if (!ok) return fail("rename failed");

lib/ota/src/file_receiver.h

@@ -34,6 +34,9 @@ class FileReceiver {
     // Takes bytes for the current chunk; returns how many were used (none while a chunk waits).
     size_t feed(const uint8_t* data, size_t len, uint32_t nowMs);
     void chunkWritten(bool ok, uint32_t nowMs);
+    // While Finishing: the SHA-256 of the file as read back from the card. The checksum on the
+    // received bytes doesn't prove the card kept them (a failed write can lose buffered data).
+    void cardChecked(const uint8_t digest[32]);
     void finished(bool ok);
     void tick(uint32_t nowMs);
     void reset() { *this = FileReceiver(); }

lib/release/src/http_head.cpp

@@ -0,0 +1,158 @@
+#include "http_head.h"
+
+#include <algorithm>
+#include <cctype>
+#include <cstdlib>
+
+namespace roro::release {
+
+namespace {
+std::string lower(std::string s) {
+    for (char& c : s) c = static_cast<char>(std::tolower(static_cast<unsigned char>(c)));
+    return s;
+}
+}  // namespace
+
+size_t HttpHeadParser::feed(const char* data, size_t len) {
+    size_t used = 0;
+    while (used < len && !complete_ && !failed_) {
+        char c = data[used++];
+        total_++;
+        if (total_ > kMaxBytes) {
+            failed_ = true;
+            break;
+        }
+        if (c == '\n') {
+            if (!line_.empty() && line_.back() == '\r') line_.pop_back();
+            line();
+            line_.clear();
+        } else {
+            line_ += c;
+        }
+    }
+    return used;
+}
+
+void HttpHeadParser::line() {
+    if (first_) {  // "HTTP/1.1 200 OK"
+        first_ = false;
+        if (line_.compare(0, 5, "HTTP/") != 0) {
+            failed_ = true;
+            return;
+        }
+        size_t space = line_.find(' ');
+        head_.status = space == std::string::npos ? 0 : std::atoi(line_.c_str() + space + 1);
+        if (head_.status < 100 || head_.status > 599) failed_ = true;
+        return;
+    }
+    if (line_.empty()) {
+        complete_ = true;
+        return;
+    }
+    size_t colon = line_.find(':');
+    if (colon == std::string::npos) return;  // not a header: ignored
+    std::string name = lower(line_.substr(0, colon));
+    size_t from = line_.find_first_not_of(" \t", colon + 1);
+    std::string value = from == std::string::npos ? "" : line_.substr(from);
+    if (name == "content-length") head_.contentLength = std::atol(value.c_str());
+    else if (name == "transfer-encoding") head_.chunked = lower(value).find("chunked") != std::string::npos;
+    else if (name == "location") head_.location = value;
+    else if (name == "content-type") head_.contentType = value;
+}
+
+size_t ChunkedDecoder::decode(const uint8_t* in, size_t len, uint8_t* out) {
+    size_t written = 0;
+    for (size_t i = 0; i < len && !failed_ && state_ != State::Done; i++) {
+        uint8_t c = in[i];
+        switch (state_) {
+            case State::Size: {
+                int digit = c >= '0' && c <= '9' ? c - '0' : c >= 'a' && c <= 'f' ? c - 'a' + 10 : c >= 'A' && c <= 'F' ? c - 'A' + 10 : -1;
+                if (digit >= 0) {
+                    if (remaining_ > (SIZE_MAX >> 5)) failed_ = true;
+                    remaining_ = remaining_ * 16 + digit;
+                    anyDigit_ = true;
+                } else if (c == ';' && anyDigit_) {
+                    state_ = State::Extension;
+                } else if (c == '\r' && anyDigit_) {
+                    state_ = State::SizeLf;
+                } else {
+                    failed_ = true;
+                }
+                break;
+            }
+            case State::Extension:
+                if (c == '\r') state_ = State::SizeLf;
+                break;
+            case State::SizeLf:
+                if (c != '\n') {
+                    failed_ = true;
+                } else if (remaining_ == 0) {
+                    state_ = State::Trailer;
+                    trailerLine_ = 0;
+                } else {
+                    state_ = State::Data;
+                }
+                break;
+            case State::Data: {
+                size_t take = std::min(remaining_, len - i);
+                for (size_t k = 0; k < take; k++) out[written + k] = in[i + k];
+                written += take;
+                remaining_ -= take;
+                i += take - 1;
+                if (remaining_ == 0) state_ = State::DataCr;
+                break;
+            }
+            case State::DataCr:
+                if (c != '\r') failed_ = true;
+                else state_ = State::DataLf;
+                break;
+            case State::DataLf:
+                if (c != '\n') {
+                    failed_ = true;
+                } else {
+                    state_ = State::Size;
+                    anyDigit_ = false;
+                }
+                break;
+            case State::Trailer:  // header lines after the last chunk, until an empty one
+                if (c == '\n') {
+                    if (trailerLine_ == 0) state_ = State::Done;
+                    trailerLine_ = 0;
+                } else if (c != '\r') {
+                    trailerLine_++;
+                }
+                break;
+            case State::Done: break;
+        }
+    }
+    return written;
+}
+
+Url parseUrl(const std::string& url) {
+    Url u;
+    size_t scheme = url.find("://");
+    if (scheme == std::string::npos) return u;
+    std::string s = lower(url.substr(0, scheme));
+    if (s != "http" && s != "https") return u;
+    u.https = s == "https";
+    size_t hostStart = scheme + 3, pathStart = url.find('/', hostStart);
+    std::string authority = url.substr(hostStart, pathStart == std::string::npos ? std::string::npos : pathStart - hostStart);
+    u.path = pathStart == std::string::npos ? "/" : url.substr(pathStart);
+    if (authority.empty() || authority.find('@') != std::string::npos) return u;  // no credentials in a URL
+    size_t colon = authority.rfind(':');
+    u.port = u.https ? 443 : 80;
+    if (colon != std::string::npos) {
+        u.port = std::atoi(authority.c_str() + colon + 1);
+        authority.resize(colon);
+        if (u.port <= 0 || u.port > 65535) return u;
+    }
+    for (unsigned char c : authority)
+        if (!(std::isalnum(c) || c == '.' || c == '-')) return u;
+    for (unsigned char c : u.path)
+        if (c <= ' ' || c == 0x7F) return u;
+    u.host = lower(authority);
+    u.ok = !u.host.empty();
+    return u;
+}
+
+}  // namespace roro::release

lib/release/src/http_head.h

@@ -0,0 +1,62 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <string>
+
+namespace roro::release {
+
+// The status line and headers of an HTTP/1.1 response, read as bytes arrive.
+struct HttpHead {
+    int status = 0;
+    long contentLength = -1;  // -1: not given
+    bool chunked = false;
+    std::string location, contentType;
+};
+
+class HttpHeadParser {
+   public:
+    static constexpr size_t kMaxBytes = 4096;
+
+    // Takes bytes up to and including the blank line that ends the head; returns how many it used.
+    // What follows is the body.
+    size_t feed(const char* data, size_t len);
+    bool complete() const { return complete_; }
+    bool failed() const { return failed_; }
+    const HttpHead& head() const { return head_; }
+
+   private:
+    void line();
+
+    HttpHead head_;
+    std::string line_;
+    size_t total_ = 0;
+    bool first_ = true, complete_ = false, failed_ = false;
+};
+
+// Takes the chunks of "Transfer-Encoding: chunked" apart as they arrive.
+class ChunkedDecoder {
+   public:
+    // `out` has room for `len` bytes (the body is never longer than what carried it).
+    size_t decode(const uint8_t* in, size_t len, uint8_t* out);
+    bool done() const { return state_ == State::Done; }
+    bool failed() const { return failed_; }
+
+   private:
+    enum class State : uint8_t { Size, Extension, SizeLf, Data, DataCr, DataLf, Trailer, Done };
+    State state_ = State::Size;
+    size_t remaining_ = 0;
+    bool anyDigit_ = false, failed_ = false;
+    size_t trailerLine_ = 0;
+};
+
+// "https://git.twis.la/twisla/x/releases/download/v1/a.ota" taken apart. Only http and https.
+struct Url {
+    bool ok = false;
+    bool https = false;
+    std::string host, path;  // path from the first "/", with its query; "/" if none
+    int port = 0;
+};
+Url parseUrl(const std::string& url);
+
+}  // namespace roro::release

lib/release/src/json_scan.cpp

@@ -0,0 +1,202 @@
+#include "json_scan.h"
+
+namespace roro::release {
+
+namespace {
+bool space(char c) { return c == ' ' || c == '\t' || c == '\r' || c == '\n'; }
+bool continuation(char c) { return (static_cast<uint8_t>(c) & 0xC0) == 0x80; }
+}  // namespace
+
+void JsonScanner::feed(const char* data, size_t len) {
+    for (size_t i = 0; i < len && !failed_; i++) step(data[i]);
+}
+
+std::string JsonScanner::path() const {
+    std::string p;
+    for (const Frame& f : stack_) {
+        if (f.isObject) {
+            if (!p.empty()) p += '.';
+            p += f.key;
+        } else {
+            p += '[' + std::to_string(f.index) + ']';
+        }
+    }
+    return p;
+}
+
+void JsonScanner::append(const char* bytes, size_t n) {
+    if (text_.size() + n > max_) {
+        truncated_ = true;
+        return;
+    }
+    text_.append(bytes, n);
+}
+
+void JsonScanner::appendCodePoint(uint32_t cp) {
+    char b[4];
+    size_t n;
+    if (cp < 0x80) {
+        b[0] = static_cast<char>(cp);
+        n = 1;
+    } else if (cp < 0x800) {
+        b[0] = static_cast<char>(0xC0 | (cp >> 6));
+        b[1] = static_cast<char>(0x80 | (cp & 0x3F));
+        n = 2;
+    } else if (cp < 0x10000) {
+        b[0] = static_cast<char>(0xE0 | (cp >> 12));
+        b[1] = static_cast<char>(0x80 | ((cp >> 6) & 0x3F));
+        b[2] = static_cast<char>(0x80 | (cp & 0x3F));
+        n = 3;
+    } else {
+        b[0] = static_cast<char>(0xF0 | (cp >> 18));
+        b[1] = static_cast<char>(0x80 | ((cp >> 12) & 0x3F));
+        b[2] = static_cast<char>(0x80 | ((cp >> 6) & 0x3F));
+        b[3] = static_cast<char>(0x80 | (cp & 0x3F));
+        n = 4;
+    }
+    append(b, n);
+}
+
+void JsonScanner::startString(bool key) {
+    inString_ = true;
+    isKey_ = key;
+    escape_ = false;
+    unicodeLeft_ = 0;
+    highSurrogate_ = 0;
+    truncated_ = false;
+    text_.clear();
+}
+
+void JsonScanner::stringChar(char c) {
+    if (unicodeLeft_ > 0) {
+        int digit = c >= '0' && c <= '9' ? c - '0' : c >= 'a' && c <= 'f' ? c - 'a' + 10 : c >= 'A' && c <= 'F' ? c - 'A' + 10 : -1;
+        if (digit < 0) return fail();
+        unicode_ = unicode_ * 16 + digit;
+        if (--unicodeLeft_ == 0) {
+            if (unicode_ >= 0xD800 && unicode_ < 0xDC00) {
+                highSurrogate_ = unicode_;  // the low half comes next
+            } else if (unicode_ >= 0xDC00 && unicode_ < 0xE000 && highSurrogate_) {
+                appendCodePoint(0x10000 + ((highSurrogate_ - 0xD800) << 10) + (unicode_ - 0xDC00));
+                highSurrogate_ = 0;
+            } else {
+                appendCodePoint(unicode_);
+                highSurrogate_ = 0;
+            }
+        }
+        return;
+    }
+    if (escape_) {
+        escape_ = false;
+        switch (c) {
+            case 'n': append("\n", 1); break;
+            case 't': append("\t", 1); break;
+            case 'r': append("\r", 1); break;
+            case 'b': append("\b", 1); break;
+            case 'f': append("\f", 1); break;
+            case 'u': unicodeLeft_ = 4; unicode_ = 0; break;
+            default: append(&c, 1); break;  // \" \\ \/
+        }
+        return;
+    }
+    if (c == '\\') {
+        escape_ = true;
+    } else if (c == '"') {
+        endString();
+    } else {
+        append(&c, 1);
+    }
+}
+
+void JsonScanner::endString() {
+    inString_ = false;
+    // A cut can leave half a character at the end.
+    while (truncated_ && !text_.empty()) {
+        size_t k = text_.size();
+        while (k > 0 && continuation(text_[k - 1])) k--;
+        if (k == 0) break;
+        uint8_t lead = static_cast<uint8_t>(text_[k - 1]);
+        size_t want = lead >= 0xF0 ? 4 : lead >= 0xE0 ? 3 : lead >= 0xC0 ? 2 : 1;
+        if (text_.size() - (k - 1) < want) text_.resize(k - 1);
+        break;
+    }
+    if (isKey_) {
+        stack_.back().key = text_;
+        expect_ = Expect::Colon;
+        return;
+    }
+    sink_(path(), text_, true, truncated_);
+    valueDone();
+}
+
+void JsonScanner::endLiteral() {
+    inLiteral_ = false;
+    sink_(path(), text_, false, false);
+    valueDone();
+}
+
+void JsonScanner::valueDone() {
+    if (stack_.empty()) {
+        done_ = true;
+        return;
+    }
+    expect_ = Expect::CommaOrEnd;
+}
+
+void JsonScanner::step(char c) {
+    if (inString_) return stringChar(c);
+    if (inLiteral_) {
+        if (space(c) || c == ',' || c == '}' || c == ']') {
+            endLiteral();  // and the character that ended it is read again below
+        } else {
+            if (text_.size() < max_) text_ += c;
+            return;
+        }
+    }
+    if (space(c)) return;
+    switch (expect_) {
+        case Expect::Value:
+            if (c == '{') {
+                stack_.push_back({true, "", 0});
+                expect_ = Expect::KeyOrEnd;
+            } else if (c == '[') {
+                stack_.push_back({false, "", 0});
+                expect_ = Expect::Value;
+            } else if (c == ']' && !stack_.empty() && !stack_.back().isObject && stack_.back().index == 0) {
+                stack_.pop_back();  // an empty array
+                valueDone();
+            } else if (c == '"') {
+                startString(false);
+            } else if (c == '-' || (c >= '0' && c <= '9') || c == 't' || c == 'f' || c == 'n') {
+                inLiteral_ = true;
+                text_.assign(1, c);
+            } else {
+                fail();
+            }
+            return;
+        case Expect::KeyOrEnd:
+            if (c == '"') startString(true);
+            else if (c == '}') {
+                stack_.pop_back();
+                valueDone();
+            } else fail();
+            return;
+        case Expect::Colon:
+            if (c == ':') expect_ = Expect::Value;
+            else fail();
+            return;
+        case Expect::CommaOrEnd:
+            if (c == ',') {
+                if (stack_.back().isObject) expect_ = Expect::KeyOrEnd;
+                else {
+                    stack_.back().index++;
+                    expect_ = Expect::Value;
+                }
+            } else if ((c == '}' && stack_.back().isObject) || (c == ']' && !stack_.back().isObject)) {
+                stack_.pop_back();
+                valueDone();
+            } else fail();
+            return;
+    }
+}
+
+}  // namespace roro::release

lib/release/src/json_scan.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <string>
+#include <vector>
+
+namespace roro::release {
+
+// Reads JSON as it arrives, a chunk at a time, and reports each plain value (a string, a number,
+// true, false, null) with where it was found: "tag_name", "assets[1].name", "[2].draft". Nothing
+// is kept but the path, so a 33 KB list of releases costs a few hundred bytes. A value longer than
+// `maxValueBytes` is cut (never in the middle of a character) and reported as truncated.
+// Meant for a server's answer, not for validating JSON: it only refuses what it can't follow.
+class JsonScanner {
+   public:
+    using Sink = std::function<void(const std::string& path, const std::string& value, bool isString, bool truncated)>;
+
+    explicit JsonScanner(Sink sink, size_t maxValueBytes = 300) : sink_(std::move(sink)), max_(maxValueBytes) {}
+
+    void feed(const char* data, size_t len);
+    bool failed() const { return failed_; }
+    bool done() const { return done_ && !failed_; }  // the top-level value is complete
+
+   private:
+    enum class Expect : uint8_t { Value, KeyOrEnd, Colon, CommaOrEnd };
+    struct Frame {
+        bool isObject;
+        std::string key;
+        int index;
+    };
+
+    void step(char c);
+    void startString(bool key);
+    void stringChar(char c);
+    void appendCodePoint(uint32_t cp);
+    void endString();
+    void endLiteral();
+    void valueDone();
+    void append(const char* bytes, size_t n);
+    std::string path() const;
+    void fail() { failed_ = true; }
+
+    Sink sink_;
+    size_t max_;
+    std::vector<Frame> stack_;
+    Expect expect_ = Expect::Value;
+    bool inString_ = false, isKey_ = false, escape_ = false, inLiteral_ = false;
+    int unicodeLeft_ = 0;
+    uint32_t unicode_ = 0, highSurrogate_ = 0;
+    bool truncated_ = false;
+    std::string text_;
+    bool failed_ = false, done_ = false;
+};
+
+}  // namespace roro::release

lib/release/src/release_info.cpp

@@ -0,0 +1,80 @@
+#include "release_info.h"
+
+#include <cstdlib>
+
+namespace roro::release {
+
+namespace {
+bool endsWith(const std::string& s, const char* tail) {
+    size_t n = std::char_traits<char>::length(tail);
+    return s.size() >= n && s.compare(s.size() - n, n, tail) == 0;
+}
+}  // namespace
+
+std::string firstParagraph(const std::string& text, bool truncated) {
+    size_t end = text.find("\n\n");
+    size_t crlf = text.find("\r\n\r\n");
+    if (crlf != std::string::npos && (end == std::string::npos || crlf < end)) end = crlf;
+    std::string p = text.substr(0, end);
+    size_t first = p.find_first_not_of(" \t\r\n");
+    if (first == std::string::npos) return "";
+    p.erase(0, first);
+    while (!p.empty() && (p.back() == ' ' || p.back() == '\t' || p.back() == '\r' || p.back() == '\n')) p.pop_back();
+    if (truncated && end == std::string::npos) p += "...";
+    return p;
+}
+
+ReleaseReader::ReleaseReader(size_t maxReleases)
+    : scanner_([this](const std::string& path, const std::string& text, bool isString, bool truncated) {
+          value(path, text, isString, truncated);
+      }),
+      max_(maxReleases) {}
+
+void ReleaseReader::end() { flushAsset(); }
+
+void ReleaseReader::flushAsset() {
+    if (assetRelease_ >= 0 && assetRelease_ < static_cast<int>(releases_.size()) && endsWith(assetName_, ".ota") && !assetUrl_.empty()) {
+        releases_[assetRelease_].otaUrl = assetUrl_;
+        releases_[assetRelease_].otaSize = assetSize_;
+    }
+    assetRelease_ = assetIndex_ = -1;
+    assetName_.clear();
+    assetUrl_.clear();
+    assetSize_ = 0;
+}
+
+void ReleaseReader::value(const std::string& path, const std::string& text, bool isString, bool truncated) {
+    size_t index = 0;
+    std::string rest = path;
+    if (!path.empty() && path[0] == '[') {  // a list: "[2].tag_name"
+        char* end;
+        index = static_cast<size_t>(std::strtol(path.c_str() + 1, &end, 10));
+        rest = *end == ']' ? std::string(end + 1) : "";
+        if (!rest.empty() && rest[0] == '.') rest.erase(0, 1);
+    }
+    if (index >= max_) return;
+    if (releases_.size() <= index) releases_.resize(index + 1);
+    Release& r = releases_[index];
+
+    if (rest == "tag_name") r.tag = text;
+    else if (rest == "published_at") r.published = text;
+    else if (rest == "body") r.notes = firstParagraph(text, truncated);
+    else if (rest == "draft") r.draft = text == "true";
+    else if (rest == "prerelease") r.prerelease = text == "true";
+    else if (rest.compare(0, 7, "assets[") == 0) {
+        char* end;
+        int j = static_cast<int>(std::strtol(rest.c_str() + 7, &end, 10));
+        if (static_cast<int>(index) != assetRelease_ || j != assetIndex_) {
+            flushAsset();
+            assetRelease_ = static_cast<int>(index);
+            assetIndex_ = j;
+        }
+        std::string field = *end == ']' && end[1] == '.' ? std::string(end + 2) : "";
+        if (field == "name") assetName_ = text;
+        else if (field == "size") assetSize_ = static_cast<uint32_t>(std::strtoul(text.c_str(), nullptr, 10));
+        else if (field == "browser_download_url") assetUrl_ = text;
+    }
+    (void)isString;
+}
+
+}  // namespace roro::release

lib/release/src/release_info.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+#include "json_scan.h"
+
+namespace roro::release {
+
+// What the device needs to know about one Gitea release (docs/milestones/R1.md, #6).
+struct Release {
+    std::string tag;        // "v0.10.0"
+    std::string published;  // "2026-10-06T08:11:31Z"
+    std::string notes;      // the first paragraph of the text: the tag's message
+    std::string otaUrl;     // where the signed Update File is
+    uint32_t otaSize = 0;
+    bool draft = false, prerelease = false;
+
+    // Something that can be installed and that the project meant to publish (drafts and
+    // pre-releases are left out for now: a release channel is #53).
+    bool usable() const { return !draft && !prerelease && !tag.empty() && !otaUrl.empty(); }
+    std::string date() const { return published.substr(0, 10); }  // "2026-10-06"
+};
+
+// Reads Gitea's answer as it arrives: `releases/latest` (one object) or `releases?limit=N` (a list).
+class ReleaseReader {
+   public:
+    explicit ReleaseReader(size_t maxReleases = 10);
+
+    void feed(const char* data, size_t len) { scanner_.feed(data, len); }
+    void end();  // after the last chunk
+    bool ok() const { return !scanner_.failed(); }
+    bool complete() const { return scanner_.done(); }
+    const std::vector<Release>& releases() const { return releases_; }
+
+   private:
+    void value(const std::string& path, const std::string& text, bool isString, bool truncated);
+    void flushAsset();
+
+    JsonScanner scanner_;
+    size_t max_;
+    std::vector<Release> releases_;
+    int assetRelease_ = -1, assetIndex_ = -1;
+    std::string assetName_, assetUrl_;
+    uint32_t assetSize_ = 0;
+};
+
+// The first paragraph of a release's text, trimmed; "..." if the text was cut before it ended.
+std::string firstParagraph(const std::string& text, bool truncated);
+
+}  // namespace roro::release

lib/release/src/update_check.cpp

@@ -0,0 +1,15 @@
+#include "update_check.h"
+
+#include "http_head.h"
+
+namespace roro::release {
+
+bool trustedAssetUrl(const std::string& url, const std::string& host, const std::string& repo) {
+    Url u = parseUrl(url);
+    if (!u.ok || !u.https || u.port != 443 || u.host != host) return false;
+    std::string prefix = "/" + repo + "/releases/download/";
+    return u.path.compare(0, prefix.size(), prefix) == 0 && u.path.find("..") == std::string::npos &&
+           u.path.find('?') == std::string::npos && u.path.find('#') == std::string::npos;
+}
+
+}  // namespace roro::release

lib/release/src/update_check.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <string>
+
+#include "release_info.h"
+#include "version_compare.h"
+
+namespace roro::release {
+
+// Where the project's releases are (Q164). A fork changes these, and its own signing key.
+constexpr const char* kGiteaHost = "git.twis.la";
+constexpr const char* kGiteaRepo = "twisla/roro9stack";
+
+inline bool versionNewer(const std::string& a, const std::string& b) { return versionOlder(b, a); }
+
+// Is `release` a newer one than what runs?
+inline bool isNewer(const Release& release, const std::string& running) {
+    return release.usable() && versionNewer(release.tag, running);
+}
+
+// Should the background check say so (Q166, Q168)? Not for a version that failed on this device
+// before (it rolled back), and not twice for the same one.
+inline bool shouldAnnounce(const Release& latest, const std::string& running, const std::string& failed, const std::string& announced) {
+    return isNewer(latest, running) && latest.tag != failed && latest.tag != announced;
+}
+
+// Is `url` a download this device takes from the project's server, for this repository? Whatever
+// the API says, the device only fetches from where it asked (a redirected or rewritten answer
+// can't send it elsewhere).
+bool trustedAssetUrl(const std::string& url, const std::string& host = kGiteaHost, const std::string& repo = kGiteaRepo);
+
+}  // namespace roro::release

lib/services/src/power_policy.cpp

@@ -10,7 +10,10 @@ bool PowerPolicy::activity(uint32_t nowMs) {
 }
 
 ScreenState PowerPolicy::update(uint32_t nowMs) {
-    uint32_t idle = nowMs - lastActivityMs_;
+    // Activity stamped from a clock read after this pass's nowMs (the Debug Console's `key`) is in
+    // the future, not 49 days ago: unsigned, the screen went off for a tick and ate the next key.
+    int32_t since = static_cast<int32_t>(nowMs - lastActivityMs_);
+    uint32_t idle = since < 0 ? 0 : static_cast<uint32_t>(since);
     state_ = idle >= offMs_ ? ScreenState::Off : idle >= dimMs_ ? ScreenState::Dimmed : ScreenState::On;
     if (notifying_) {
         if (static_cast<int32_t>(nowMs - notifyUntilMs_) >= 0)

lib/services/src/settings.cpp

@@ -1,5 +1,8 @@
 #include "settings.h"
 
+#include "debug_auth.h"
+#include "ipv4.h"
+
 namespace roro {
 
 namespace {
@@ -29,6 +32,19 @@ const Definition kDefinitions[] = {
     {"sound", Kind::Bool, 1, nullptr, 0, 1},
     {"probe_mac_raw", Kind::Bool, 1, nullptr, 0, 1},
     {"wifi_on", Kind::Bool, 1, nullptr, 0, 1},
+    {"gnss_on", Kind::Bool, 1, nullptr, 0, 1},
+    {"coord_dms", Kind::Bool, 0, nullptr, 0, 1},
+    {"lora_preset", Kind::Int, 0, nullptr, 0, 6},  // LongFast first
+    {"dns1", Kind::String, 0, "9.9.9.9", 7, 15},  // Quad9
+    {"dns2", Kind::String, 0, "1.1.1.1", 0, 15},  // Cloudflare
+    {"dns_always", Kind::Bool, 0, nullptr, 0, 1},
+    {"ntp1", Kind::String, 0, "pool.ntp.org", 1, 63},
+    {"ntp2", Kind::String, 0, "time.cloudflare.com", 0, 63},
+    {"gnss_quiet", Kind::Bool, 0, nullptr, 0, 1},  // off: GNSS stays on, as decided in M2 (Q58)
+    {"check_updates", Kind::Bool, 1, nullptr, 0, 1},  // on: it only looks, and says so (R1, Q165)
+    {"debug_on", Kind::Bool, 0, nullptr, 0, 1},  // off: nothing listens until the owner says so (Q189)
+    {"debug_token", Kind::String, 0, "", 0, 64},  // empty, or a valid token
+    {"help_told", Kind::Bool, 0, nullptr, 0, 1},
 };
 static_assert(sizeof(kDefinitions) / sizeof(kDefinitions[0]) == static_cast<size_t>(Setting::Count),
               "every Setting needs a definition");
@@ -81,6 +97,12 @@ bool Settings::validString(Setting s, const std::string& value) const {
             if (value == region) return true;
         return false;
     }
+    uint32_t address;
+    if (s == Setting::Dns1) return net::parseIpv4(value, address);
+    if (s == Setting::Dns2) return value.empty() || net::parseIpv4(value, address);
+    if (s == Setting::Ntp1) return net::validHost(value);
+    if (s == Setting::Ntp2) return value.empty() || net::validHost(value);
+    if (s == Setting::DebugToken) return value.empty() || debug::validToken(value);
     return true;
 }
 

lib/services/src/settings.h

@@ -21,6 +21,19 @@ enum class Setting : uint8_t {
     Sound,            // bool
     ProbeMacRaw,      // bool: probe-request Logs keep raw MAC addresses
     WifiEnabled,      // bool: the Wi-Fi Service stays Connected when a Saved Network is in range
+    GnssEnabled,      // bool: the GNSS Service reads the receiver (M2, Q58)
+    CoordinatesDms,   // bool: show degrees, minutes and seconds instead of decimal degrees (Q64)
+    LoraPreset,       // int: the LoRa Scanner's Meshtastic preset, an index into the EU868 list (M3, Q95)
+    Dns1,             // string: the first DNS server, an IPv4 address (S1, Q108, Q109)
+    Dns2,             // string: the second, or empty
+    DnsAlways,        // bool: use them on Automatic (DHCP) networks too, instead of DHCP's
+    Ntp1,             // string: the first NTP server, a host name or an IPv4 address (S1, Q110)
+    Ntp2,             // string: the second, or empty
+    GnssQuietForLora, // bool: put the GNSS receiver in standby while the LoRa radio listens (issue #20)
+    CheckUpdates,     // bool: look for a newer release on Gitea once a day (R1, Q165)
+    DebugConsole,     // bool: the Debug Console listens on Wi-Fi (ADR 0010, Q189: off unless switched on)
+    DebugToken,       // string: its token, tidied (debug_auth.h); empty until the console is first switched on
+    HelpTold,         // bool: this device has been told about the help key once (issue #69, Q201)
     Count
 };
 

lib/services/src/storage_monitor.cpp

@@ -24,7 +24,7 @@ void StorageMonitor::update(bool present, uint64_t totalBytes, uint64_t usedByte
 
     if (next.present && next.level >= 80 && !warned_) {
         warned_ = true;
-        bus_.publish(Event::withText(EventType::Notification, "SD card over 80% full",
+        bus_.publish(Event::withText(EventType::Notification, "SD card over 80% full: see Storage",
                                      static_cast<int32_t>(NotificationLevel::Warning)));
     }
 }