CAN IDs (CAN sniff logs collections)

General discussion about interfacing with the CAN bus
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kleverevelk
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Joined: 2015 Jan 12 16:52

CAN IDs (CAN sniff logs collections)

Post by kleverevelk » 2015 Jan 12 17:58

May be my demand is unusual, but I need this information.

The topic is OBDII CAN diagnostics.
Diagnostic equipment (Scanner) sends requests, ECU/ABS/... responds.


ISO 15765-4 defines the Scanner_request, ECU_response CAN IDs:
29-bit:
request: 0x18DB33F1 (functional), 0x18DAxxF1 (physical)
response: 0x18DAF1xx (functional)
where: xx=ECU_number
11-bit:
request: 0x7DF (functional), 0x7Ex (physical)
response: 0x7Ey (functional)
where: y=x+8


The most of vehicles use ISO 15765-2 normal addressing.
Especially for not ECU nodes (ABS,Airbag and others).
Nodes' CAN IDs are defined by manufacturer.

I need to study request-response CAN IDs linkage if it has a place.
For example, I discovered the linkage for VAG vehicles: Response_ID = Request_ID+0x6A (11-bit IDs).
For Ford and Mazda: Response_ID = Request_ID+0x8 (11-bit IDs).
I am not sure it is a strict rule for both cases, but I checked several car models and nodes for both groups. The rules are observed.


I need at least one log for Vehicle-Scanner connection for every vehicle vendor (BMW,Mersedes and others) to study the {Request_ID,Response_ID} values.
Then using my kit and scanner I can check if the linkage hypothesis is right or not. But I need the values to make the hypothesis.
I scan vehicles myself, but the process is very long.

May be somebody may share his log collection. Or give me some advise, search direction.

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