NES 2.0 Mapper 336
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NES 2.0 mapper 336 is used for multicarts containing several UNROM games. Its UNIF board name is BMC-K-3046.
Submapper 0:
- 11-in-1 (K-3046)
- 2-in-1 (YH-217)
- 4-in-1 (YH-4109)
Submapper 1 (M1K30 PCB):
- Top Gun III 2-in-1
Submapper 2:
- 2-in-1 (YH-218)
Banks
- CPU $8000-$BFFF: Switchable 16 KiB inner PRG-ROM bank and switchable 128 KiB outer PRG-ROM bank
- CPU $C000-$FFFF: Fixed 16 KiB inner PRG-ROM bank #7 and switchable 128 KiB outer PRG-ROM bank
- PPU $0000-$1FFF: Unbanked 8 KiB CHR-RAM
Data Latch ($C000-$FFFF)
Mask: $8000 D~7654 3210 --------- ..OO OIII || |+++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF ++-+---- Select 128 KiB outer PRG-ROM bank at CPU $8000-$FFFF | +---- Mirroring (Submapper 2), 1=H, 0=V +------- Mirroring (Submappers 0/1), 1=H, 0=V
Note
Submappers 0 and 2 have no bus conflicts. Submapper 1 does: D0-D2 are affected by normal AND-type bus conflicts, while D3 has a resistor in the signal path to ensure that the ROM bit always "wins", similar to INES Mapper 144. This behavior is necessary for proper function.