antus you misunderstand me. J2534 is completely capable. The only reason for writing an ELM327 wrapper is so applications written for ELM327 (like logging programs) can use the J2534 interface. The vehicle programming will be handled by the J2534 directly and natively (as in no wrapper on top of it)...

I forgot the most important part: I haven't found any open source GM Diagnostic software compatible with J2534. The cost of entry for this is super small. Really... like the price of a normal ELM327. The parts I am working on right now are proper detection of connected J2534 devices (0404) and being...

I will be programming by bench most likely but I don't have the shit together for it yet except the PCM itself. It came out of a Sunfire I engine swapped (and PCM/harness swapped) to Ecotec... The reason I am layering ELM327 is to test the underlying software I am writing that simplifies packet tran...

It looks like I will be using com0com or parts of it to make a Virtual COM port to emulate ELM327 commands through the j2534 interface. That will be my first step.

@Taylor I ebayed the $25 J2534 VCI. It is listed to work with Toyotas. The idea behind this is that no wiring is necessary because I intend to program the PCM the same way a dealer would upgrade the PCM software. They simply plug into the OBDII port (I'm in the U.S. so its standard), connect over J1...

Also, should I create a Windows COM wrapper for J2534 and make it act like ELM? That way you could use the same cable for just about everything. (it would share a common library for J2534 functions with the other [reflashing] program. Also, Antus, the link you posted before with the 1997 pcm... is t...

It looks like GM-LAN is just CAN (ISO 15765-2). Looks like they dropped the low speed bus altogether.

I am still working on this project... slowly. I acquired a PCM from a 2001 Sunfire to play with. Anyone have any insight on how to set a PCM up on the bench for tinkering?

That is some super cool stuff! I wonder if they ever realized they could have just used the CarDAQ unit to do all of those things. Could have saved them lots of time they spent building the Python wrappers for the other hardware's API.

@Tazzi J2534 (when J1850VPW is supported) allows for 4k transfers. The PassThruIoctl function needs called to change the mode to high speed for programming, but it appears to be independent of frame size (which is always at a maximum of 4096 bytes PLUS headers). Also, I am not building a custom devi...

THANK YOU SO MUCH! That is exactly what I was looking for/needed! Now I can make mroe progress in my freetime.