FYI: tc@tunercat.com replied to my email and said that they don't have anything for this VCM.
FYI: tc@tunercat.com replied to my email and said that they don't have anything for this VCM.
That doesn't surprise me. But did they offer any hints about programming?Originally Posted by ReadyXB
No, just the typical comment that it was "...an odd-ball VCM that was only used in that one year for the S10." But I appreciate their taking the time to reply.
I've got my eye on a ROM burner, and I'm also looking for a debugger that would work with the D87M microcontroller. It seems that GM did wire up the required debug traces out to that large, unpopulated 3x30 header at the bottom of the board.
So the two flash ROMs definitely have an odd/even data storage going on. Should be loads of fun.
Great.
I can make you a disassembly when you post the bins.
Do you know how to swap bytes.
I am sure one bin will contain abs logic and the other will be for engine calibration.
I will take you up on that!
Here are links for the two flash ROMs images. I called them ROM "A" and ROM "B".
I mentioned that my soldering skills were quite good. However, my "unsoldering" skills... not so much. I managed to rip a few traces off of the board during the process. Thankfully, my repairs were successful (well, my truck cranks and runs).
I also added ROM sockets in the hopes that we can identify key areas in these ROMs that apply to the base fuel map, DTC masks.
Yes, and I merged A+B into this ROM: BSLL_AN28F512_merged_A+B.bin. A=even, B=odd. I chose A+B instead of B+A because I stumbled upon my VIN in the ROMs: half in ROM A and half in B! A+B made a correct VIN string. Of course it could be B+A, and if so, here is that file: BSLL_AN28F512_merged_B+A.bin
Is it possible that not all areas of the ROMs are interpolated even/odd? I need to trace the address and data lines for both ROMs. I do know that all other pins on the ROMs are directly connected to each other, including CE/chip enable. Again, I think that only the data lines are separate between the ROMs but I need to check again. It was late and I was tired, lol.
So my newly rebult engine is running quite well but I definitely need to tune a few areas. For example, I'm hoping to find a way to modify the BLM min value as it appears to never go below 108 for my idle cell (usually 0). The problem is, every time I re-enter the idle zone, Integrator re-starts at 128 and takes 17 seconds to decrease and stabilize at around 97/98 for a happy 14.7 closed loop idle. Very frustrating. Better yet would be the ability to modify the base fuel map so I can get BLM/Integrator back near 128.
I built an ALDL cable a few days ago. 8192 baud communication using Realterm. I now also have a bluetooth module working because I was getting too cold sitting in the truck outside for hours, lol. Now I can play on the couch.
So far, I have only been able to successfully request the Mode 1 datastream (F4,57,01,00,B4). Here is a sample reply:
Mode 10 also works. Requests for Mode 2 memory go unanswered. I would LOVE to snoop while a Tech 1/Tech 2 does a programming update and see all the magic, lol. Any pointers would be appreciated. My goal would be the ability to read/write a new tune over ALDL. Next best is to successfully disassemble the ROMs so I could reprogram them on my burner.F4 82 01 00 00 00 43 7C 03 00 CA 00 00 80 00 00 0B E3 04 1A 00 78 00 00 50 00 00 00 00 00 43 78 8A 88 00 50 00 00 00 00 00 00 25 CA 09 04 04 8C
To be honest, I'm amazed this all still works. I rebuilt almost everything - engine and tranny, lol. It was my first time doing a manual transmission. Complete engine rebuild with all new do-dads and a 266HR Comp Cams camshaft. And, obviously, I even touched the computer.
Last edited by ReadyXB; 12-29-2014 at 07:23 AM.
I'm making some good progress on decoding the ROM. I've located a few tables but definitely still have a ton to go.
Posting Permissions
Reply With Quote
Bookmarks