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Re: '99 Saturn Dissassembly

Posted: Fri Jan 15, 2010 3:00 pm
by sabercatpuck
By the way, these are some of the numbers on the IC's on the board just in case it helps:
185
16196452
e87j (this is the 68hc11F1)

18391m64
66285
delco 466

a8372y25
39194
delco 466

a8393p53
51862
delco 466

16132083
a 9832 736 (date code?)
m832316apa

flash
AN28f010 (the flash rom)

185
16185984
2e79n (68hc56fn, the dlc I/O device)

16132083
a 9833 736 (date code?)
m83309apa

18412r31
66285
delco 466

a8403m42
51862
delco

05799
t8383655
466

Re: '99 Saturn Dissassembly

Posted: Fri Jan 15, 2010 4:18 pm
by antus
How does it compare to our VY pcm, pictured here?

https://pcmhacking.net/forums/viewtopi ... 52&start=0

Re: '99 Saturn Dissassembly

Posted: Sat Jan 16, 2010 12:29 am
by sabercatpuck
Here is what mine looks like

Re: '99 Saturn Dissassembly

Posted: Sat Jan 16, 2010 9:05 am
by antus
Is that socketed chip the flash? Nice of them to do that if it is! Looks like its got the space to add an nvram if you wanted to start thinking about realtime tuning.

Re: '99 Saturn Dissassembly

Posted: Sat Jan 16, 2010 10:04 am
by sabercatpuck
Yes the socketed chips are the flashes, but they did not come that way. I picked up a monster bag of them off ebay. It worked out I could have 4 for 4 bucks or 200 for 5 bucks, so I went with the 200. I might even use them all one of these days :). I might have to ohm out the pins on that and see if that is what it is there for. Next up is to install the headder pins so I can hook up the logic analyzers.

Re: '99 Saturn Dissassembly

Posted: Sun Jan 17, 2010 11:44 pm
by sabercatpuck
Well I found out that I am going to need some isolation on the probe tips as the la is affecting the signals. I will either need to get some components or buy some flying leads with the isolation built in.

Re: '99 Saturn Dissassembly

Posted: Tue Jan 19, 2010 11:31 am
by sabercatpuck
I got a few legs of the isolation network in and was able to start getting some meaningful data even off of just the address lines. I will hopefully be able to finish up the interface soon, then with any luck be able to start identifying stuff soon.

Re: '99 Saturn Dissassembly

Posted: Tue Jan 19, 2010 11:49 am
by VL400
Great stuff, am just working through some of the code for a 2003 VY commodore PCM. Certainly a whole new ball game these new(ish) PCMs. Would kill to have a multi channel logic analyser, i had access to a 64ch LA but it has gone MIA :(

Re: '99 Saturn Dissassembly

Posted: Tue Jan 19, 2010 5:00 pm
by sabercatpuck
Yeah it is nice to have a logic analyzer it really makes it easy to see what is going on. One of the things I noticed earlier was that there was a call to the $5666 page swapping routine and it put it in upper memory bank 3. I was running my seed key bully program in the background at the time, but I want to get my data channels hooked in before I confirm where the section of code is. I figure it will start jumping out then.

Re: '99 Saturn Dissassembly

Posted: Wed Jan 20, 2010 12:49 pm
by sabercatpuck
Well I know memory location $0088 definitely has something to do with inputs from the scan tool, I set obd2crazy up to ping away at mode $22 pid's and found that activity with that location picked up when I was pinging. I am trying to work my way through the code to find out where the big decision to process commands on the port.