Self-made altitude sensor: ESP32-C3 SuperMini + BMP280 broadcasting pressure and
temperature over standard BLE Environmental Sensing. Read into baldav the same way as
the heart-rate strap (Kotlin BLE service -> file -> Rust -> JS), new device_type 'baro'.
- BleHrService: 'baro' type subscribes to ESS 0x181A (pressure 0x2A6D uint32 0.1 Pa,
temperature 0x2A6E int16 0.01 C), writes ble_baro_data.json + ble_baro_log.jsonl.
Every baro branch is gated by deviceType=='baro', so HR/GPS paths are untouched.
- ble.rs: BaroReading, ESS detection, ble_get_baro command (Android reads the file,
desktop returns None). Registered in lib.rs.
- frontend/js/baro.js: passive window.BARO - hypsometric pressure->altitude using the
sensor temperature, anchored to GPS altitude at ride start. Nothing runs until
BARO.start(), so with no barometer the app is unchanged.
- tools/baro-sensor: firmware (PlatformIO main.cpp + Arduino sketch) that reads BMP280
at max oversampling and advertises the ESS service.
Prep only: no hardware yet, verified by compile (build 0.1.538). Live wiring and
ride-track integration pending the board.
4aiman
82f3dc9d4a