iNES Mapper 227 denotes an address-latch-based multicart circuit board (PCB code 810449-C-A1 among others) mounting 1 MiB of PRG-ROM plus 8 KiB of unbanked CHR-RAM.
A variant used by Chinese RPGs from Nanjing, Waixing (PCB code FW-01) and Yancheng adds 8 KiB battery-backed WRAM and does not implement the UNROM-like bankswitching modes.
Other PCB that use this mapper :
Nestopia Plus! has defined submappers 0 and 1:
[A~1... .mLQ OQQP PpMS]
||| |||| |||+-0: PRG A14=p
||| |||| ||| 1: PRG A14=CPU A14
||| |||| ||+- 0: Vertical mirroring
||| |||| || 1: Horizontal mirroring
||| |||+-++-- PRG A16..A14 (inner bank)
||+-|++------ PRG A19..A17 (outer bank)
|| +-------- 0: When CPU A14=1: PRG A16..14=LLL
|| 1: When CPU A14=1: PRG A16..14=PPp
|+----------- Value for PRG A16..14 when CPU A14=1 and O=0
+------------ 0: PRG A3..A0=CPU A3..A0
1: PRG A3..A0=Solder pad 3-0 (submapper 1 only)
Power-on value: 0
Effective meaning:
Bit 9 Bit 7 Bit 0 Meaning $200s $080s $001s (L) (O) (S) 0 0 0 Switchable inner 16 KiB bank PPp at CPU $8000-$BFFF, fixed inner bank #0 at CPU $C000-$FFFF (UNROM-like with fixed bank 0) 0 0 1 Switchable inner 16 KIB bank PP0 at CPU $8000-$BFFF, fixed inner bank #0 at CPU $C000-$FFFF (UNROM-like with only even banks reachable, pointless) 1 0 0 Switchable inner 16 KiB bank PPp at CPU $8000-$BFFF, fixed inner bank #7 at CPU $C000-$FFFF (UNROM) 1 0 1 Switchable inner 16 KIB bank PP0 at CPU $8000-$BFFF, fixed inner bank #7 at CPU $C000-$FFFF (UNROM with only even banks reachable, pointless) ? 1 0 Switchable 16 KiB inner bank PPp at CPU $8000-$BFFF, mirrored at CPU $C000-$FFFF (NROM-128) ? 1 1 Switchable 32 KiB inner bank PP at CPU $8000-$FFFF (NROM-256)
Categories: INES Mappers, Mappers with CHR RAM, Multicart mappers