1982 ECM Rom type????????

[Christian Hack]

Hiya people,

While you guys have your PROM data books out you can probably
help me with another PROM I have found in my Nissan ECU
It's a Fujitsu MB7132E. A quick search on the web revealed it's
some sort of programmable device (pretty much all the hits I got
were device lists for EPROM programmers and the like). I am
guessing it's a 2732 (4k x 8) look a like at the moment.

Anyone got any ideas as to why there would be two ROMs/PROMs
in my ECU? I have the code PROM out and disassembled and I
can't see any reference to this new PROM at all. One thing I'm
pretty sure of is that it's not a backup style Memcal thingo which
the GM computers use since if the main PROM is not there, the
car won't go at all. There is a fairly large 64 pin ASIC on the
board, could it possibly be a processor as well?

Another thing, why a PROM and not a Masked ROM like the main
CPU code?

Thanks

Christian Hack
christianh at edmi.com.au
EDMI Pty Ltd
Ph : (07) 3888 3066
FAX : (07) 3888 3583