Ang: Re: Ang: RE: [Gmecm] New ROM-code in a 1227747?

[Robert W Hughes]

> with the ROM inside the CPU I see the difficulties.
> Thanks for clearing that out for me.
> 
> /Per

The later P4 ecms have all the software in the removable prom, the 
earlier C3 ecms have onboard ROM, don't know which type the 7747 is. 
Ludis's "spit" routines are intended to dump the onboard non-removable 
ROM of the C3. The hidden connector at the other end of the ecm has all 
the bus signals and something called "ROMEN" which would suggest you 
could dump the onboard ROM, program it into an external PROM and connect 
it with the proper addressing logic to this connector and then use the 
ROMEN signal to disable the onboard ROM. If this works (I haven't tried 
it) you could then modify any part of the software.
-- 
Robert W. Hughes (Bob)
BackYard Engineering
29:40.237N, 95:28.726W or perhaps 30:55.265N, 95:20.590W
Houston, Texas "The city with too much Oxygen"
rwhughe at oplink.net