iz8dwf | Commodore PET 2001 repair. RAM/ROM daughterboard comes to rescue. @iz8dwf | Uploaded April 2018 | Updated October 2024, 1 hour ago.
Commodore PET 2001 repair. I've been given a first revision 2001 PCB with missing 6550s and 6540s. These chips are rare enough that finding a complete set nowadays is almost hopeless. It would be also pointless (and more expensive) to use 16 adapters to replace all 6550s and 7 adapters to replace all the 6540s. What makes sense in this case is to use a daughterboard with RAM and ROM replacement.
Whoever sold this board also made sure that the only two 6550s left were also defective and the only 6540 left, the character generator one, was defective too.
Second revision of the PET RAM/ROM board here:
youtube.com/watch?v=bjyGk5zoDMs
Commodore PET 2001 repair. I've been given a first revision 2001 PCB with missing 6550s and 6540s. These chips are rare enough that finding a complete set nowadays is almost hopeless. It would be also pointless (and more expensive) to use 16 adapters to replace all 6550s and 7 adapters to replace all the 6540s. What makes sense in this case is to use a daughterboard with RAM and ROM replacement.
Whoever sold this board also made sure that the only two 6550s left were also defective and the only 6540 left, the character generator one, was defective too.
Second revision of the PET RAM/ROM board here:
youtube.com/watch?v=bjyGk5zoDMs
