There are not many games that use this board, so it's hard to test things: Kaiketsu Yanchamaru 3, Spartan X 2, Daiku no Gen San 2.
Is it known what 0x9000 and 0x9001 do ? 0x9001.7 probably is the mirroring switch, but I don't know about the other bits. Spartan X 2 writes to 0x9000.6 (0x40), the other games write 0 to it.
Is it known what 0x9000 and 0x9001 do ? 0x9001.7 probably is the mirroring switch, but I don't know about the other bits. Spartan X 2 writes to 0x9000.6 (0x40), the other games write 0 to it.