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Contributing Vehicle Decoding

Please have vehicle decoding contributions be in the following format:

Below is an example with a single entry, for multiple signals just include more entries.

[
  {
    "name": "vehicleSpeed",
    "comment": "front left wheel speed, kmh",
    "header": "7df",
    "mode": "22",
    "pid": "1135",
    "formula": "python:bytes_to_int(messages[0].data[-2:]) * 0.05625",
    "interval_seconds": 10,
    "protocol": "6",
    "can_flow_control_clear": true,
    "can_flow_control_id_pair": "713,77D",
    "can_flow_control_filter": "607,FFF",
    "can_extended_address": "07"
  }
]

Explanation

If you're using an autopi to decode, with eg. the obd.query command, you will notice we're just parameterizing the requests into a json format.

  • name: can be anything, as long as it makes sense. We'll convert it to the right thing in our model-garage COVESA spec
  • comment: any useful info, the units eg. kmh, degrees Celcius
  • header,mode,pid: bytes in HEX format (not decimal format)
  • can_flow: all optional, just depending if the vehicle needs them to be decoded.
  • interval_seconds: optional, we'll most likely determine how often this signal should be queried
  • formula: how to decode the incoming bytes.
    • Prepend with python: if it is just using the built-in autopi formula.
    • Prepend with dbc: (prefered, but may not be possible for all scenarios) if you can use the standard dbc formula to decode the bytes. tooling here example: 24|16@1+ (0.125,0) [0|8031.875] "rpm"
    • Prepend with custom: if this needs special logic or just easier to explain in words, eg. "may return 1 or 2 frames, single byte after the PID convert to decimal". We'll figure out code to process.