When buying a MVS cart the seller threw in a untested MV-1FZ board.
When I connected the board to the supergun and powered on with no game it is reporting a Backup Ram Error - WRITE 0000 READ 1000
Can anybody assist in helping to diagnose this fault? At my disposal I have my working MV-1FZ board with Unibios which I can drop into the other board.
If I understand correctly it may mean the ram chips need to be changed but equally well it could just be a trace problem on the board.
Can anybody point me to what pin on which chip I can try bridging (and with what) to rule out the trace problem?
WRITE 0000 = 00000000
READ 1000 = 00010000
If I am correct the problem is the 5th bit - can you advise what data pin and on which chip this corresponds to and to which pin on the cpu this should go?
Any other ideas are welcome.
When I connected the board to the supergun and powered on with no game it is reporting a Backup Ram Error - WRITE 0000 READ 1000
Can anybody assist in helping to diagnose this fault? At my disposal I have my working MV-1FZ board with Unibios which I can drop into the other board.
If I understand correctly it may mean the ram chips need to be changed but equally well it could just be a trace problem on the board.
Can anybody point me to what pin on which chip I can try bridging (and with what) to rule out the trace problem?
WRITE 0000 = 00000000
READ 1000 = 00010000
If I am correct the problem is the 5th bit - can you advise what data pin and on which chip this corresponds to and to which pin on the cpu this should go?
Any other ideas are welcome.