'87 eprom
Thread Starter
Pro
Joined: Apr 2003
Posts: 552
Likes: 13
From: Oz
'87 eprom
I have a memcal from an 87 I am trying to modify.
The few I have done in the past have all been 27c128's and 256's, but this one is different....
My PP2 read it ok when configured to 27c128, I have erased it, but now i am having trouble writing to it..
Can anyone identify it for me??
The few I have done in the past have all been 27c128's and 256's, but this one is different....
My PP2 read it ok when configured to 27c128, I have erased it, but now i am having trouble writing to it..
Can anyone identify it for me??
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
That should be a 27C128 prom. The reason that you can't reprogram the chip is that sometimes GM programmed them at a higher than rated programming voltage. What happens then is that doing this renders the prom as a one time program only chip. You may have to use one of Moates piggy back adapters with a Atmel 29C256 or an SST 27SF256 chip on the board. Using these chips means you would have to stack the programs but that is easy to do.
www.moates.net
Check out Craigs website for additional information.
www.moates.net
Check out Craigs website for additional information.
Thread Starter
Pro
Joined: Apr 2003
Posts: 552
Likes: 13
From: Oz
Thanks! I'll just replace the chip with one of the 27c256's i have laying about and stack the bin. There's no real need for an eeprom in this case, I'm just adjusting fan temps for a friend and there won't be a need for any further changes..
