can GM eproms be reflashed??
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From: Orange Park Florida
can GM eproms be reflashed??
IF so, then rework should be easy, just UV the damn things and reprogramme with an adaptor feeding through the cal pak....NO???
if not, why not???
GENE
if not, why not???
GENE
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Re: can GM eproms be reflashed?? (mrvette)
That's what I do.... erase 'em, then burn 'em.
Melting Slicks
Joined: Aug 2001
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From: Lockport NY
Re: can GM eproms be reflashed?? (mrvette)
Yup, that's about it. Most use a modified IDE cable header; Traxions promintro over at DIY-PROM details this.
There's also a thread there right now that gives insight into why some PROM burns fail...It seems that it takes longer to erase a 27C128 via UV each time you burn it...The thread says after as little as 10 burns, it can take over an hour to erase, and it may still fail to limp-mode when in use...
http://www.thirdgen.org/techbb2/show...threadid=75332
Like many others here, I've desoldered the GM EPROM from my MemCal and soldered in a lo-mount ZIF socket, and burn to a 29C256 chip, which is Flash programmable. I choose to "double" my code, so even though the ECM (supposedly) only reads from high memory, I have the lower 128k covered as well.
BTW: Mike Davis estimated that it took 400 burns to get his chip "right on".
[Modified by Rich B., 7:23 PM 1/7/2002]
There's also a thread there right now that gives insight into why some PROM burns fail...It seems that it takes longer to erase a 27C128 via UV each time you burn it...The thread says after as little as 10 burns, it can take over an hour to erase, and it may still fail to limp-mode when in use...
http://www.thirdgen.org/techbb2/show...threadid=75332
Like many others here, I've desoldered the GM EPROM from my MemCal and soldered in a lo-mount ZIF socket, and burn to a 29C256 chip, which is Flash programmable. I choose to "double" my code, so even though the ECM (supposedly) only reads from high memory, I have the lower 128k covered as well.
BTW: Mike Davis estimated that it took 400 burns to get his chip "right on".
[Modified by Rich B., 7:23 PM 1/7/2002]
Melting Slicks
Joined: Aug 2001
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From: Lockport NY
Re: can GM eproms be reflashed?? (KYVette90)
Can you save the original program in case you need to go back?
Sounds complicated; but the first time you burn a lower fan temp (the easiest mod) and install it and see it actually *work*, you start feeling pretty confident about it all...
