: Reading .Bins from proms?



botboy
01-24-05, 08:15 PM
Alright, somebody clear this up please:

I've been told by someone on a fiero forum that GM has some sort of prom for the OBD-1 northstars that will erase itself if the attempt is made to read a .bin file from the EEPROM.

Obviously this measure, if true, was made to prevent reverse-engineering the EEPROM, but I'm curious if anyone can confirm/deny whether or not there is any truth to this? I want to reverse engineer the EEPROM....

eldorado1
01-24-05, 11:16 PM
That may be true. Cadillac seems to be very, very secretive when it comes to their computers/PROMs. Unlike Ford which is practically open source (perhaps their only redeeming quality http://cadillacforums.com/forums/images/smilies/icon_rolleyes.gif )

botboy
01-28-05, 02:58 PM
According to Scot Sealander on the GMECM list:


It is just an EPROM, not an EEPROM. I bought a NorthStar MEMCAL from
eBay, and it didn't destruct when I read it. ;-) Hard to imagine the
technology that would have to go into a GM PROM to get it to do that.
Go ahead and read the PROM without fear. It does have some different
code it it though, it is not like the usual GM code.

Scot

32V_DOHC
01-28-05, 11:19 PM
The memcal consists of 2 normal 27C512 EPROMS. The one under the ESC module is controls the trans idle cruise VATS fans etc. The other one controls the engine fuel spark egr etc.

ALso I disagree about the usual code. It is quite normal when compared to other GM PCMs using the 68hc11 processor. It is only different viewed from the 6801, 6805, 6809 veiwpoint. The HC11 requires more setup (reset) coding and has some extra index and accumulator function that are able to be used. However it is pretty standard stuff.

John

CharBroiled
02-01-05, 05:52 PM
I agree that it cant erase itself. EPROMS are EPROMS, period. And its "read" all the time by the processor. How would it be able to tell if its being read by the CPU or somethimg else? Answer: it cant.

botboy
02-08-05, 07:03 PM
The memcal consists of 2 normal 27C512 EPROMS. The one under the ESC module is controls the trans idle cruise VATS fans etc. The other one controls the engine fuel spark egr etc.

ALso I disagree about the usual code. It is quite normal when compared to other GM PCMs using the 68hc11 processor. It is only different viewed from the 6801, 6805, 6809 veiwpoint. The HC11 requires more setup (reset) coding and has some extra index and accumulator function that are able to be used. However it is pretty standard stuff.

John

I can't get PM's to work - could you please email me botboy60 (at) hotmail.com or kris (at) speedyoldtruck.com? I have some more questions

I'm really interested in getting together a tunerpro definition file for the OBD-1 northstars.

botboy
02-15-05, 07:57 PM
bump...32v_dohc...please get back to me...