9e1ca98a5d
Source, state, artist/title/album, position and duration (from cspot's playback state, so it matches the app), volume and `can`. cspot patch 0004 adds read getters for the playback state and context. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
9.3 KiB
9.3 KiB
aes67-ESP32-P4
AES67 sender on a Waveshare ESP32-P4-ETH (PoE). Sources: Spotify Connect (cspot) and HLS/m3u8, with failover. Riedel-style web UI and a reusable AES67 core (PTP, RTP TX, SDP/SAP, VLAN, syslog, health) meant for later AES67 projects.
Repo: https://gitea.apointless.space/bsncubed/aes67-ESP32-P4
Read first
docs/aes67-core-base.md: reusable core. Config schema, API, PTP (roles, Riedel defaults, status fields), AES67 TX/SDP/SAP, VLAN, syslog, temperatures, component layout.docs/hardware-and-design-notes.md: board pinout, chip revision caveat, project pipeline (cspot/HLS), failover, player API.web/index.html: finished web UI (single file). It is the API contract; firmware must match the JSON it reads and writes.
Working rules
- One change at a time ("one fuckup at a time"). Change or test one variable per step; never stack several fixes or hypotheses. If something breaks, go back to the last known-good state.
- Follow the build order below. Finish and verify a step on hardware before starting the next.
- After every change:
idf.py build, flash, and check the serial monitor output. Show the relevant log lines. - Don't mark a step done until it has been verified on the board.
- Keep core and project separate:
components/aes67_*must not depend onmain/(sources/player). Project code plugs in through the config, status and route registries. web/index.html: keep the CORE / PROJECT markers. If the firmware needs an API change, change the doc and the page together.- Small, focused commits per step.
Toolchain
- ESP-IDF 5.5 or later (needed for the P4 and for
examples/network/vlan_support). Targetesp32p4. idf.py set-target esp32p4,idf.py build,idf.py -p <PORT> flash monitor- Before first build: run
esptool.py chip_idandesptool.py flash_id.- Chip revision < v3.0 (engineering silicon, seen on some of these boards) needs
CONFIG_ESP32P4_SELECTS_REV_LESS_V3=y. Our board: v1.3 (set in sdkconfig.defaults, min rev v1.0). - Our board: 32 MB flash (GigaDevice c8/4019). App slots must stay below 16 MB (cache mapping above 16 MB is experimental in IDF).
- Rev < 3 also limits Espressif's prebuilt audio libraries:
esp_audio_codecmust stay < 2.6 andesp_audio_effects< 1.4 (newer versions use P4 assembly that needs rev >= 3; the build fails with a message saying so). Check this for any new Espressif binary component.
- Chip revision < v3.0 (engineering silicon, seen on some of these boards) needs
- Embed
web/index.htmlviaEMBED_TXTFILESinaes67_web. - cspot (Spotify,
external/cspotgit submodule, philippe44 fork, pinned): after cloning rungit submodule update --init external/cspot && git -C external/cspot submodule update --init cspot/bell. Its nanopb code generator needs, in the IDF Python env:python -m pip install protobuf grpcio-tools 'setuptools<81'(after. export.sh). Our fixes to cspot/bell live incomponents/spotify/patches/{cspot,bell}/*.patchand are applied automatically at configure time; don't edit the submodule directly, add a patch. - Flash over the network (normal way since step 2b; keep USB for recovery):
curl -f --data-binary @build/aes67_p4.bin -H 'Content-Type: application/octet-stream' http://p4-aes67/api/otaThe board reboots into the new image on trial; checkGET /api/otashows the new version withpending_verify: false. - Serial: opening /dev/ttyACM0 can reset the board. Don't open it while an OTA image is on trial (a reset then counts as a failed boot and rolls back).
- Rollback test build (self-test always fails), in its own build dir:
idf.py -B build-selftest-fail -DSDKCONFIG=build-selftest-fail/sdkconfig -DSDKCONFIG_DEFAULTS="sdkconfig.defaults;sdkconfig.selftest_fail" build
Board quick reference (full details in docs)
- Ethernet: IP101GRI, RMII, PHY addr 1, ref clock from PHY into GPIO50 (EMAC_CLK_EXT_IN). MDC 31, MDIO 52, PHY reset/power 51, TX_EN 49, TXD0 34, TXD1 35, CRS_DV 28, RXD0 29, RXD1 30.
- No Wi-Fi/BT on this board.
- On-die temperature sensor only (driver/temperature_sensor.h).
Build order / status
- 0. Check chip revision and flash size; create IDF project and empty component stubs (layout in aes67-core-base.md). Set up the OTA partition table (two app slots, no factory) and PROJECT_VER from git now, so the layout never changes later.
- 1. Ethernet: IP101 up, DHCP, IP logged. Ping works.
- 2. Web server + config store (cJSON in NVS) + embedded index.html; /api/config, /api/status (stub values), /api/reboot.
- 2a. Finding the device: mDNS (hostname.local + _http._tcp), then LLDP (switch shows name + IP).
- 2b. Firmware update: /api/ota upload + rollback self-test. Test: update to a new build, then deliberately flash a build that fails its self-test and confirm it rolls back. After this, flash over the network; keep USB for recovery.
- 3. PTP TimeReceiver: lock to an existing GM (Riedel), fill
status.ptp. Confirm EMAC hardware timestamps work. First check whether the installed ESP-IDF has a PTP example/component for the P4 before writing one. - 4. AES67 TX with a 1 kHz test tone, PTP-paced; /stream.sdp. Verify: import SDP on a Riedel Artist 4-wire AES67 port, and check packets/timestamps in Wireshark. Done and checked with a receiver script (all ptimes, L16/L24, tone phase-locked to PTP); still open: the Riedel import and a Wireshark capture.
- 5. SAP discovery, then syslog, then health/temperatures (one at a time). VLAN split moved to phase 2.
- 6. PTP TimeTransmitter: BMCA roles (auto/master), hybrid mode.
- 7. Sources: HLS player, then cspot (Spotify Connect), then failover + /api/player.
- 7.1-7.4 HLS plays on AES67 (PSRAM ring, TS demux + AAC, 44.1 -> 48 kHz). Tested with Triple J Hottest (TS, AAC-LC 44.1k).
- Come back to HLS (open items):
- Clock drift: the station's encoder clock vs our PTP clock is not corrected. Starts 3 segments (~30 s) behind live, so it shows after hours/days (skip when falling out of the live window, or buffering). Fix: steer the 44.1 -> 48 kHz ratio by a few ppm from the distance to the live edge / ring level.
- Download speed ~1.4 Mbit/s over TLS (fine for ~250 kbit/s; tune buffer sizes / per-chunk overhead).
- Not yet tested: HE-AAC variant (140k), other stations, fMP4/ADTS-only playlists, discontinuities (#EXT-X-DISCONTINUITY), network loss and recovery, long runs.
- Audio starts only after PTP lock (~20 s after boot): intended, TX needs PTP.
- cspot (Spotify Connect): login, audio, pause/skip/seek, app volume, live mode switching work; stays connected across track changes and past 6 min (7.5b). Fixed so far: logger NULL crash, Vorbis symbol clash, volume starting at 0, reconnect race (PR #3 patch), 6-minute AP resets (delayed Pong patch), app dropping the device (notifyAudioReachedPlayback). Open:
- OTA with a session: now ends the session first; 2 of 2 uploads with a running session were clean since. Flash writes still stall TX > 20 ms during uploads (stream stutters while updating).
- First connects sometimes fail ("Can't connect to spotify servers"), a retry works.
- Internal heap drops from ~365 KB to ~231 KB with a session; check what can move to PSRAM.
- Track display in the app can switch ~3-5 s early.
- Mute at 0 % volume not yet confirmed.
- Consider offering the delayed-Pong fix upstream (philippe44/cspot).
- An old, long-idle session can get out of sync with the app: it sends empty Load frames ("No tracks in frame") instead of Pause/Play, so controls do nothing. Quitting and reopening Spotify on the Mac fixes it.
- failover (auto mode): no session or (with
failover_on_pause) paused forfailover_delay_s-> HLS; Spotify playing -> Spotify within ~1 s; 30 ms fades; HLS suspended while Spotify plays; cspot is held back (not drained) while it isn't Spotify's turn, so it resumes where it paused. Verified: no session -> HLS, play -> Spotify, pause stays (on_pause off), pause -> HLS after 5 s (on_pause on), play -> Spotify at the paused position.- Open:
aes67_tx resync(TX 20-27 ms late) ~11 s after each switch to Spotify (seen 3 times); clicks at switches not yet checked in a recording; HLS start sometimes hits CDN read timeouts.
- Open:
- /api/player: GET done (source, state, track, position as the app shows it, volume, can). Next: transport POSTs, seek/volume, source override/url.
- 8. Mono sum, gain, polish.
Phase 2 (parked)
- VLAN split: AES67 untagged + internet tagged (inet.vlan_id/pcp), per aes67-core-base.md "Network". Needs a tagged VLAN with DHCP on the switch port. Config group
inetand the UI fields exist already; nothing is applied yet. - NTP (SNTP): servers as hostnames or IPs (e.g.
pool.ntp.org, several allowed; names resolved via DNS, re-resolved on failure). Uses: seed the PTP clock with real time before becoming GM (today it starts at 1970), syslog timestamps. Needs atimeconfig group + UI fields (change doc and page together).
Phase 3 (parked)
- Remote access via VPN / Tailscale. There is no official Tailscale client for ESP32; options to evaluate first:
(a) no firmware change: a Tailscale subnet router on the LAN (e.g. the dev PC or a Pi) advertising the device's subnet;
(b) WireGuard on the device (e.g. the
esp_wireguardcomponent) to a WireGuard server or a Tailscale/Headscale-compatible peer. Before exposing the web/API remotely: add authentication (bearer token) as noted in the OTA/security section of aes67-core-base.md. Keep AES67/PTP traffic off the tunnel.