When I first started looking at the 3.5 and 4.2 vortec engines I thought they had e40 ecu.

The P12 has a Am29BL802C memory chip 512K x16 bits. Just putting this here so it doesn't get lost.

I took a break from this, but I finally figured out that you shouldn't send anything after the mode 34.

Here is a successful request/response

6C10F134DD
6CF0107400441E

This is very different then the way PCMhammer operates. I believe the entire kernel must be sent in one transfer.

do a search for "KWP2000 pdf" on google and you will find it. you want the "14230-3.pdf". The positive response ("44") is defined in that protocol.

I don't have a bin for this PCM, but I did find a Windows XP image!

I tried using CAN bus with this PCM (P12). The Trailblazer didn't have CAN bus lines in its wiring diagram, but the Cars that use the P12 PCM do have CAN bus in there wiring diagram. It didn't work. Of course, it could be some wiring issue. The 7F indicates a negative response and the 12 on the end ...

Never mind, I see that the chip is mapped to addresses 000000 - $7FFFFF.

What is "00 10 00" within the 0x34 command? Your trying to write to the very last area in ram prior to the registers.

Getting Window XP is proving to be difficult.

Didn't work ...
b'STPX H:6C10F0, R:1, D:2701\r'
b'STPX H:6C10F0, R:1, D:2701\r670116E8\r\r>'
b'STPX H:6C10F0, R:1, D:2702D5AA\r670234\r\r>'
b'STPX H:6C10F0, R:1, D:34001000ff6250\r7F34001000FF6212\r\r>'

Where is the processor RAM in memory vs. the flash chip?

The main chip is P/N 263 09394824 K62K. The memory controller is AM29BL802CB-65RZE.

I don't think the memory search is going to bear fruit. Does this output make sense? STPX H:6C10F0, R:1, D:2701 67014B25 >STPX H:6C10F0, R:1, D:2702F344 670234 >STPX H:6C10F0, R:1, D:2701 67010000 >STPX H:6C10F0, R:1, D:340010001BBE1E 7F340010001BBE12 I purchased a VXDIAG plug, and tried to install ...