INES Mapper 154
iNES Mapper 154 represents NAMCOT-3453, a board used only for the game Devil Man.
It is identical to Mapper 88, but with the addition of a single bit allowing for one-screen nametable control:
$8000-$9FFF: [..xx xxxx]: See mapper 206 documentation
$8000-$FFFF: [.N.. ....]
N = Nametables
0 = 1ScA
1 = 1ScB
Note that the nametable control bit is present over the entire 32kB range; unlike the associated Namco 108 which is only present at $8000-$9FFF.
Like mapper 88, if the CHR ROM is larger than 65536 bytes, CHR ROM A16 is connected to PPU A12. This means content in the left pattern table ($0xxx) comes from the first 64kB of CHR-ROM and content in the right pattern table ($1xxx) comes from the last 64kB of CHR-ROM.