I have a dead Waku Waku 7 cart that just boots to Cross Hatch Test when plugged in, which I guess means that the MVS doesn't detect it as a cart. Happens on different motherboards.
I also have a working Waku Waku 7 and have isolated the issue to the prog board (by swapping PCBs between carts until I found the broken one).
I did inspect all joints through a microscope, washed the PCB thoroughly and then tried to probe away at it with a scope, but not really sure what the best way to approach doing that is.
I see some action on the address busses of the ROMs, and they both have voltages... but that's about it.
CE is LOW, OE is HIGH on all of them which means they are in "Output deselect".
Nothing looks obviously wrong, so I'm sortof at a loss for what the next step to do here is.
Desolder all roms, dump them and make sure they seem correct? Otherwise replace the ones that are not?
What would you typically check on a small board with basically just ROMs like this.
Pics of my setup:
The working PCBs running:
I also have a working Waku Waku 7 and have isolated the issue to the prog board (by swapping PCBs between carts until I found the broken one).
I did inspect all joints through a microscope, washed the PCB thoroughly and then tried to probe away at it with a scope, but not really sure what the best way to approach doing that is.
I see some action on the address busses of the ROMs, and they both have voltages... but that's about it.
CE is LOW, OE is HIGH on all of them which means they are in "Output deselect".
Nothing looks obviously wrong, so I'm sortof at a loss for what the next step to do here is.
Desolder all roms, dump them and make sure they seem correct? Otherwise replace the ones that are not?
What would you typically check on a small board with basically just ROMs like this.
Pics of my setup:
The working PCBs running: