BigDaddyCainer
New Member
Hi All.
Just wondering if you can help. I have an old PET 3008 which won't power up.
The CRT comes up O.K but the screen is full of characters. I am guessing this is because the ram isn't being cleared down.
I have a Hameg scope and have checked out the data and address busses - they run briefly and then hang. Looking at the Chip Select on the ROM's - the highest Kernal is goes high, blips and then stays low - I'm guessing that it's either RAM or the ROM is duff.
I have read the other ROMS using a Willem programmer and home made adapter, and whilst what I get isn't 100% correct, I am at least getting something recognisable from three out of the four.
The last rom I just get patterns of garbage from - so I thought it must be duff.
I managed to get hold of some 2732 EEprom chips...these have a nearly comparable pinout to the 6332 just pins 18 and 21 are different.
I made my own adapter (correct I think) and inserted it but am getting the same problem.
Has anyone any advice or have you made adapters to get the 2732 EEPROM's to work in the PET's?
Would love to get it going - had some success with the PSU of an SX-64 recently and it's now my pride and Joy!
Hope you can help!
Cheers,
BigDaddyCainer
Just wondering if you can help. I have an old PET 3008 which won't power up.
The CRT comes up O.K but the screen is full of characters. I am guessing this is because the ram isn't being cleared down.
I have a Hameg scope and have checked out the data and address busses - they run briefly and then hang. Looking at the Chip Select on the ROM's - the highest Kernal is goes high, blips and then stays low - I'm guessing that it's either RAM or the ROM is duff.
I have read the other ROMS using a Willem programmer and home made adapter, and whilst what I get isn't 100% correct, I am at least getting something recognisable from three out of the four.
The last rom I just get patterns of garbage from - so I thought it must be duff.
I managed to get hold of some 2732 EEprom chips...these have a nearly comparable pinout to the 6332 just pins 18 and 21 are different.
I made my own adapter (correct I think) and inserted it but am getting the same problem.
Has anyone any advice or have you made adapters to get the 2732 EEPROM's to work in the PET's?
Would love to get it going - had some success with the PSU of an SX-64 recently and it's now my pride and Joy!
Hope you can help!
Cheers,
BigDaddyCainer