I originally accidentally posted in the wrong section so not everyone I've mentioned this to has seen it - so reposted here and linked from the original.
I've had someone's Mr Do board to repair for far too long now, so to make life easier I've modified the other test ROMs I've done to work with Mr Do.
It tests the programme RAM, background and foreground RAM, then sits at a screen showing the status of the inputs and DIP switches in real time. Has been tested in Mame and on an original Universal board.
The test ROM has shown the foreground RAM being faulty on the board I have to repair so now need to spend some time working with the schematics
Photo of the foreground RAM error, and the input and DIP switch testing screen image attached.
The test ROM code is also attached. Burn the code to a 2764 and replace the EPROM at a4 (a4-01.bin in Mame)
I've had someone's Mr Do board to repair for far too long now, so to make life easier I've modified the other test ROMs I've done to work with Mr Do.
It tests the programme RAM, background and foreground RAM, then sits at a screen showing the status of the inputs and DIP switches in real time. Has been tested in Mame and on an original Universal board.
The test ROM has shown the foreground RAM being faulty on the board I have to repair so now need to spend some time working with the schematics
Photo of the foreground RAM error, and the input and DIP switch testing screen image attached.
The test ROM code is also attached. Burn the code to a 2764 and replace the EPROM at a4 (a4-01.bin in Mame)
Attachments
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