[Gmecm] New ROM-code in a 1227747?

[Greg Parmer]

Correct--ROM is in the CPU. Correct--removing the CPU and replacing it would be
a huge job. It is not correct that you *must* use that on board ROM, however.

Thirdgen.org seems to be down at the moment (for me anyway). Hopefully it'll be
back soon and you can read more about the ROMLess C3. Key is the "ROMEN" line.
http://www.thirdgen.org/techbb2/showthread.php?threadid=217206

This is likely above the average Joe's head, but driving once was too. There's
plenty of excellent info out there about the C3s/TBIs. Read BobR's posts very
closely, since he's the source of much (if not most) of that excellent info.

-greg


> As Dennis said,  the ROM is contained in the CPU.  Removing the CPU 
> and replacing it with 'something else' is a very big job.  You'd be 
> much better off using the thirdgen device.  It should be fairly easy 
> to accomplish your goals that way.
> 
> The CPU is a 68hc11 variant with a few special instructions,  built by 
> Motorola for GM.  You can't replace it with a commercial part without 
> re-writing the code.
> 
> Bill
> 
> > --- Per Lonnborg <perlon at passagen.se> wrote:
> >
> >> Wow!
> >> That was an impressing project going on over there, a complete new 
> >> TBI-code with better options than in many new EFI-system it seems!
> >>
> >> This was a bit more than I had plans for though, so I will ask 
> >> again if there is a possibility at all to change the onboard ROM 
> >> with "something else"?
> >>
> >> On Ludis pages there are instructions to dump the ROM-content into 
> >> a computer, so I guess the hard part is to replace that stock ROM 
> >> chip. What chip is that btw?
> >>
> >> I might add that I am quite new to both diy-efi and assembler 
> >> programming, so maybe some of my questions seems strange!
> >>
> >> Thanks,
> >>
> >> /Per