This is part of a family of Sunsoft mappers used largely by Japanese games: (iNES Mapper 089, iNES Mapper 093, iNES Mapper 184)
This mapper is used by Tenka no Goikenban: Mito Koumon (J). This game uses the Sunsoft-2 chip on the Sunsoft-3 board, and so works differently than Mapper 93
Here is the documentation in disch's original style:
Registers **BUS CONFLICTS**:
--------------------------
$8000-FFFF: [CPPP MCCC]
C = Select 8k CHR @ $0000
P = Select 16k PRG @ $8000
M = Mirroring:
0 = 1ScA
1 = 1ScB
PRG Setup:
--------------------------
$8000 $A000 $C000 $E000
+---------------+---------------+
| $8000 | { -1} |
+---------------+---------------+
Categories: In NesCartDB, Discrete logic mappers, INES Mappers