Sadly the dump we have on JAMMArcade is not working because the device is combinatorial but has latches inside and the original dumper didn't know this.Therefore it must be manually reversed.If someone can provide us the chip we can try to reverse it.
I'll dig it out again later! Hell maybe i'll finally get around to testing that mod bios now the blank carts are in
To be totally honest with ya, when i got it working it was in the cabinet for about 1 week and then boxed on the shelf as i know for a fact it's gonna go bad again.
I really don't undestand what's happening with that motherboard. I get a black screen whatever I do (with the missing IC33).
I found the Z80 is in a permanent interrupt (INT pin low) coming directly from the VDP.
VDP is fine (swapped with one from a MS).
No broken lines found whatsoever.
What's even weirder is if I burn a MS test ROM in place of the BIOS it does work fine so I know at least the MS part of my MegaPlay motherboard used for cart detection and additional overlay works.