antus wrote:sorry that was not confirmation, just my thoughts after a read for you to consider. Now im looking again I see I miss aligned one of the brackes on my scan of your post and if DAT_0003edec is not 3 it returns a 7f error. So its unlikely to be length, and instead some kind of a flag. I'd probably need to load up the project in ghidra or ida to explore a bit more to try and get further. Though I'll keep looking and post back. Starting to think CAN_TX might be a copy in to a buffer, not the actual tx, and the response struct is finished being populated by the return and tx'd somewhere else.
I think you are right though. I came to the same conclusion by another method. I compared the Node Interface Pseudo Code from some GM engineering documents to the code for several functions and it seems to be the case for every one of them. The functions start out comparing the message data length to what is expected and if not equal then CanTX= x7F, xMODE, x12.
you may be right about CANTX, those labels are not abslolute, more just indicators to help me while searching through the functions. I'll try to attach this if you're interested in looking at it. Change the .txt to a .gzf (it's a ghidra zip file that wouldn't attach in that format).