Gary C
Veteran Member
Getting lots of PET practice
Now its time for an 8032 (not an SK this time) that was working but always a bit flakey
No chirps, no screen.
Removed all but the CRTC and the CPU and installed a tynemouth board with RAM and CPU mapped out and up it comes but with ! on every odd character, its a start
PETTEST installed and ROM's mapped in and its showing no problems in the display RAM's but to be sure, I extended the test to check every location of the 80 column screen and sure enough it wont complete. As its a ! rather than a space character, its obviously bit 1 thats stuck in the odd SRAM, so swapped and screen now working.
Now, with the normal ROMS in, nothing. Kernal rom has been butchered in the past and is missing two legs for which bits of leg have been jammed in. So wrote a 2532 with the kernal and now it gives the chirps but no basic welcome. Took all the basic ROM's out and verified them in my programmer and, damn, one has bit rot. Another 2532 programmed and now its working.
It came with a tynemouth 40/80 column switchable edit ROM installed so thats three of the original ROMs missing
But at least its working.
Now its time for an 8032 (not an SK this time) that was working but always a bit flakey
No chirps, no screen.
Removed all but the CRTC and the CPU and installed a tynemouth board with RAM and CPU mapped out and up it comes but with ! on every odd character, its a start
PETTEST installed and ROM's mapped in and its showing no problems in the display RAM's but to be sure, I extended the test to check every location of the 80 column screen and sure enough it wont complete. As its a ! rather than a space character, its obviously bit 1 thats stuck in the odd SRAM, so swapped and screen now working.
Now, with the normal ROMS in, nothing. Kernal rom has been butchered in the past and is missing two legs for which bits of leg have been jammed in. So wrote a 2532 with the kernal and now it gives the chirps but no basic welcome. Took all the basic ROM's out and verified them in my programmer and, damn, one has bit rot. Another 2532 programmed and now its working.
It came with a tynemouth 40/80 column switchable edit ROM installed so thats three of the original ROMs missing
But at least its working.