tb lilley
Member
I have a couple of Robotron boards, with a fault on each.
First up:
This is a known tested working monitor. Game plays fine, but colours all wrong. Cab wiring is fine as I don't get this problem with my other Robotron board. Have swapped in known working video decoder chips - no change. Both decoder sockets test good. The board passes all ROM and RAM tests. I'm all out of ideas ... any suggestions of where to go next with this?
Next up - on my second Robotron board I have a common enough fault: CMOS RAM problems. I've had niggles with CMOS RAM on this board ever since I've had it. It used to fairly regularly lose all settings - and this could happen after the game had booted fine with no errors. Walk away and come back 10minutes later and all values set to 7. All high scores read 777777. Number of lives per player? 7777 etc etc. I thought I'd solved this when I replaced the 5114 with an NVRAM kit, but the problem soon started happening again. Last night I replaced the NVRAM kit with vanilla new 5114. Same as before, game can play fine, but keeps losing settings. At this point I'm ruling out problems with the 5114 - so where else should I be looking? Right now I cant get the game to boot with anything other than 777777s everywhere, so whatever was flakey has finally gone kaput. If it makes a difference this is a Stargate board that I've converted to Robotron - bit even when it was used with Stargate I had the exact same set of problems.
Thanks.
First up:
This is a known tested working monitor. Game plays fine, but colours all wrong. Cab wiring is fine as I don't get this problem with my other Robotron board. Have swapped in known working video decoder chips - no change. Both decoder sockets test good. The board passes all ROM and RAM tests. I'm all out of ideas ... any suggestions of where to go next with this?
Next up - on my second Robotron board I have a common enough fault: CMOS RAM problems. I've had niggles with CMOS RAM on this board ever since I've had it. It used to fairly regularly lose all settings - and this could happen after the game had booted fine with no errors. Walk away and come back 10minutes later and all values set to 7. All high scores read 777777. Number of lives per player? 7777 etc etc. I thought I'd solved this when I replaced the 5114 with an NVRAM kit, but the problem soon started happening again. Last night I replaced the NVRAM kit with vanilla new 5114. Same as before, game can play fine, but keeps losing settings. At this point I'm ruling out problems with the 5114 - so where else should I be looking? Right now I cant get the game to boot with anything other than 777777s everywhere, so whatever was flakey has finally gone kaput. If it makes a difference this is a Stargate board that I've converted to Robotron - bit even when it was used with Stargate I had the exact same set of problems.
Thanks.

