beginner-how to ID chips?

[Programmer]

Shannen,

I know what he's going through--the GM chips don't have the "normal" numbers
on them. If Greg is reading along, pretty much all the GM choices are going
to be 27C32, 27C125, 27C256 and 27C512--don't recall running into a 27C64 on
anything. I've run into Proms with a raised window--I think those ones are
25C32--in some older 1987 and down Proms. You'll also find on the 1991 and
prior 27C32's may program easier with a 27C32A setting on the programmer
(whichever one you may have). Try reading the stock chip first with the
different settings--after you get a knack for seeing what the "deciphered"
program is supposed to look like in the editor, this'll be another clue as
to the correct setting.

Hope this helps
-----Original Message-----
From: Shannen Durphey <shannen at grolen.com>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Saturday, June 05, 1999 10:21 PM
Subject: Re: beginner-how to ID chips?


>greg kring wrote:
>>
>> Just learning about chip programming. Got all the hardware, all the
>> software, just need the knowledge. Trying to just play around by copying
>> files from one chip to another. How do I identify a EPROM to use the
>> correct programming algorythms? So far I am playing with used OEM
>> general motors stuff from the 1227748 ECM. All the chips are marked
>> Delco along with bunch of numbers. Where do I go from here?
>> greg
>
>So far, the chips I've seen have a number that corresponds to a choice
>in my burner's software.  I think I've been lucky.  Look for a 2732,
>or 2732A on those chips.
>Shannen
>