Greetings!
I bought an Atari System 1 (Marble Madness) project from a fellow collector and am in the process of rebuilding the system. The issues that I can't seem to figure out are the inability to coin-up the game and lack of sound. For the coin-up, I am getting +5v to known good switches, but the game doesn't see any coin inputs when the switch is actuated. For the sound, I am hearing a low hum from the speakers and seeing the following on the Sound Test Screen:
Current Coin Value: 0 0 0
Number of Sounds: 104
Sound CPU Status: 06
Music Chip Time Out
Sound CPU Interrupt Error
I checked the voltages on the LSI main board and I am getting 5.01 VDC, 12.2 VDC (at +C84), and -17.9V (at -C83). I also re-socketed the 6502A chip at location ~J 16.
Any suggestions on what to check next?
Thanks in advance,
Chris
I bought an Atari System 1 (Marble Madness) project from a fellow collector and am in the process of rebuilding the system. The issues that I can't seem to figure out are the inability to coin-up the game and lack of sound. For the coin-up, I am getting +5v to known good switches, but the game doesn't see any coin inputs when the switch is actuated. For the sound, I am hearing a low hum from the speakers and seeing the following on the Sound Test Screen:
Current Coin Value: 0 0 0
Number of Sounds: 104
Sound CPU Status: 06
Music Chip Time Out
Sound CPU Interrupt Error
I checked the voltages on the LSI main board and I am getting 5.01 VDC, 12.2 VDC (at +C84), and -17.9V (at -C83). I also re-socketed the 6502A chip at location ~J 16.
Any suggestions on what to check next?
Thanks in advance,
Chris
