Commit Graph
2 Commits
Author SHA1 Message Date
Ashin WalpolaandClaude Opus 5 528637dab6 Fix UPER encoding of CurvatureCalculationMode; verified on hardware
CurvatureCalculationMode is the one extensible ENUMERATED in CAM:
  ENUMERATED {yawRateUsed(0), yawRateNotUsed(1), unavailable(2), ...}
UPER encodes an extensible ENUMERATED as an extension bit followed by the root
index - 1 + 2 = 3 bits. All three of our encoders wrote only the 2-bit index,
shifting yawRate and the entire low-frequency container one bit early for any
standards-compliant receiver.

It went unnoticed because every end of this project shared the mistake: the
Kotlin codec was ported bit-for-bit from cam.c, so phone and ESP32 agreed
perfectly with each other and with nothing else. Confirmed against the ETSI
ASN.1 in the C-ITS-Parser checkout, where rasn marks this type - and only this
type - #[non_exhaustive].

Fixed in all three copies of the encoder (app CamUperCodec.kt,
obu-firmware/main/cam.c, obu-cam-transmistter/main/cam.c) plus the decoder,
which now rejects rather than misreads a set extension bit. Frame size is
unchanged at 43 bytes. Transmitter reflashed and the phone decodes its CAMs.

Also in this change:

- serial_link: skip send_frame entirely when no USB host is attached, and raise
  the tx mutex timeout above the worst-case hold. With the phone unplugged every
  write blocked its full timeout while holding the lock, so forwarded CAM_RX
  traffic starved the 1 Hz heartbeat - observed as "tx mutex timeout, dropping
  frame" on the console, and it would have tripped the phone's link watchdog.
  Verified gone on hardware.
- Log decoded and failed CAMs in CamUseCaseRepository. "The app shows nothing"
  had two indistinguishable causes; a silent `?: return` made this bug much
  harder to find than it needed to be.
- Remove the ESP32 send-only/send-and-receive toggle. Reception can't be
  disabled in firmware (raw TX only works while promiscuous), so it was an
  app-side filter pretending to be a radio control.
- V2X monitor follows the serial link state on the ESP32 path instead of MQTT,
  which is permanently disconnected there; CAM intake is gated on the link being
  up, and engine state is cleared when it drops.
- About screen: 0.5.0, Phase 03.
- Track obu-cam-transmistter, the bench CAM transmitter. Its cam.c is compiled
  (unlike obu-firmware's reference copy) and must stay bit-identical to the other
  two - this commit is what that coupling costs when it's broken.
- Document the two-toolchain split: this project builds on IDF 5.5.4, obu-firmware
  on the pinned 6.1. Exporting both in one shell fails confusingly.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-11 14:50:35 +02:00
Ashin WalpolaandClaude Opus 5 f3ae81a8fe Phase 03: CAM decode coverage, real sensor data in TX, V2X monitor for ESP32 path
CAM codec:
- Stop rejecting CAMs carrying a specialVehicleContainer. It is declared last in
  CamParameters, after everything this decoder reads, so buses / emergency
  vehicles / road-works vehicles now decode for position and kinematics instead
  of being dropped outright
- Drop the lowFrequencyContainer parse - it extracted nothing into Cam, and its
  reads were only correct when no high-frequency optionals were present
- Document why the 7 optional-presence bits are consumed but not acted on: UPER
  writes a SEQUENCE's presence bitmap up front but each field's value in
  declaration order, and all seven are declared after yawRate
- Field widths and container ordering verified against the ETSI ASN.1 sources in
  the C-ITS-Parser checkout, not from memory

Transmit path:
- Own StationID is now a persisted random 32-bit value instead of a hardcoded 0.
  Receivers key on StationID to track a station across CAMs, so every unit
  broadcasting 0 made two MicrOBUs indistinguishable - including to this app's
  own detection engine
- Populate longitudinalAcceleration from successive GNSS speed samples. Not from
  the accelerometer: CAM wants signed along-track acceleration, and the raw
  sensor is device-frame with gravity in it. Null outside a usable sample gap
  rather than a fabricated value
- CAM pinger builds from live GNSS/IMU via PhoneCamBuilder instead of beaconing a
  hardcoded bench coordinate with speed and heading pinned to zero, so it now
  exercises the sensor pipeline and not just the wire. Sends nothing without a
  fix, and reports that rather than sitting at "Sent: 0"

V2X monitor:
- Received-CAM pane for the ESP32-C5 path, replacing the MQTT topic list that is
  permanently empty there. One row per station rather than per message - CAMs
  arrive at 1-10 Hz per station, so the pane is bounded by road users nearby, not
  by traffic rate. Nearest first, tinted by active alert level
- DENM hazard pins on the live map as a warning triangle, drawn above vehicle
  markers. CiT One path only: the ESP32 firmware forwards BTP-B port 2001 (CAM)
  and drops port 2002 before it reaches the phone

DenmParser uses tolerant field-name matching - the Use Case API's DENM JSON
schema is not yet confirmed against real payloads.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-10 14:09:18 +02:00