NES 2.0 Mapper 394 denotes Realtec's HSK007 multicart PCB. Unusually, it can be set to function either as an MMC3 clone or as a J.Y. Company ASIC.
Mask: unknown, but A3 must be set D~7654 3210 --------- ...M M..B | | +- PRG/CHR A18 +-+---- Mapper Mode 0: BNROM 1: MMC3 2: J.Y. Company ASIC 3: Same as 2 Power-on value: $0F
Mask: unknown, but A3 must be set D~7654 3210 --------- cC.p PBB. || | |++-- PRG A16..A15 in BNROM mode || | +---- PRG A17 if p=0 || +------ PRG A17 in MMC3 mode || 0: From Outer Bank Register (128 KiB inner bank) || 1: From MMC3 (256 KiB inner bank) |+-------- CHR A17 if c=0 +--------- CHR A17 in MMC3 mode 0: From Outer Bank Register (128 KiB inner bank) 1: From MMC3 (256 KiB inner bank) Power-on value: $10
In J.Y. Company ASIC Mode, PRG/CHR A17 always come from the J.Y. Company ASIC.
Categories: MMC3-like mappers, Mappers with scanline IRQs, Multicart mappers, Mappers with cycle IRQs