iNES Mapper 255 is apparently assigned to the 110-in-1 multicart.
A~[1BMZ PPPP PpCC CCCC]
||| |||| |||| ||||
+-----------++-++++ - Select 8 KiB CHR at PPU $0000
||| |||| ||
+---++++--++------- - Select 16 KiB PRG at CPU $8000 and $C000 if Z=1
+---++++--+-------- - Select 32 KiB PRG at CPU $8000 if Z=0
|+---------------- - Select PRG bank size: 0-32K 1-16K
+----------------- - Nametable mirroring: 0-PPUA10 ("vertical") 1-PPUA11 ("horizontal")
Hardware on the board includes
The two latches' reset inputs are tied to 5V, so the banking register boots with random contents.
This looks like a duplicate of iNES Mapper 225. It's not clear why Nestopia implemented it twice.
See also: https://forums.nesdev.com/viewtopic.php?p=209732#p209732
Categories: Discrete logic mappers, Multicart mappers