yellerjeep
New Member
- Joined
- Apr 21, 2024
- Messages
- 1
Hey fellow Commodorians!
I've taken up repairing C64s and have two successes under my belt but this one is confusing to me.
I'm using a well built Power Supply from Ray Carlsen for testing so for everything else assume that my power is good.
The unit powers up to a black screen, dead test cartridge does not produce any output either. The address and data lines show activity on the 8500R4 CPU and no chips are "hot" to the touch aside from the VIC and SID which are just moderately warm.
Other things checked:
Clock, nice solid signal.
Reset, normal high after power on.
The original owner said that it started to "hang up" with screen corruption. He'd reset the computer and it would be normal for a bit, but then crash again. Eventually it just got to this state. His power supply is a 5v brick and a 9vac brick with a cable he made.
My current working theory is that there's something wrong with the VIC. I plan to swap it with my known working 64c.
I've taken up repairing C64s and have two successes under my belt but this one is confusing to me.
I'm using a well built Power Supply from Ray Carlsen for testing so for everything else assume that my power is good.
The unit powers up to a black screen, dead test cartridge does not produce any output either. The address and data lines show activity on the 8500R4 CPU and no chips are "hot" to the touch aside from the VIC and SID which are just moderately warm.
Other things checked:
Clock, nice solid signal.
Reset, normal high after power on.
The original owner said that it started to "hang up" with screen corruption. He'd reset the computer and it would be normal for a bit, but then crash again. Eventually it just got to this state. His power supply is a 5v brick and a 9vac brick with a cable he made.
My current working theory is that there's something wrong with the VIC. I plan to swap it with my known working 64c.