MMC3 board not working but having scrabled graphics.

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MMC3 board not working but having scrabled graphics.
by on (#93284)
I'm a newbie here so hello. Anyway I thought I've done a good rewireing job but I only get scrabled graphics.
I'll try to give all info.
I took one of my own games Teenage Mutant Hero Turtles II - The Arcade Game (pal-B) having the MMC3B board trying to rewire it for eproms.
Eproms of use is 27C020. To test the art of splitting roms I retrieved a copy of my own game (the above). Splitted it to CHR 256Kb and PRG 256Kb.
I burned them with a willem PCB 5.0E board and the burner program 098D8.
To mention I checked the eproms that they where blank and the program did automatic "verify" test. Both CHR and PRG came out good. At least what the program said.
Now something I've done is good since there is a graphic at all but there is defenitly something wrong since it's not working properly.
Question is where is the fault. Any one believe its the burning process?
It's not dirty pins, I've cleaned them good. Or do you believe it's the wiring.
If it's the wiring how can I check the MMC3 board with a multimeter.
Have no idea what pins should have what reistance or so. Any help would be appreciated=)