ECU numbers on GM

[Scott Schaaf]

Ron & Cathy Webb wrote:
> 
> Recently decided to take a close look at the GM ECU for a
> project. Don't know much about them, except they are 68HC11
> based, with most of the chips identifiable.
> 
> Where can I get info on what the 7 digit ECU numbers mean?
> 1227747 means what? Is This a hardware mod, or only a firmware
> rev? Can someone point me to a compendium of what is known about
> the things, so I don't re-invent the wheel?

GOOD LUCK!!!   It APPEARS to be 68HC11,,, BUTTT,  the pinouts DO NOT
mach that of any HC11.  Nor do any of the other 54 pin chips.   I have
been trying DESPARATLY to find out about these ECMs, and to no avail. 
If you get lucky, PLEASE let me know. 
				Scott...