INES Mapper 116
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iNES Mapper 116 is used for the SOMARI-P board bearing the Huang-1 or Huang-2 ASICs and a PAL, used by releases from Gouder, also known as 哥德 (Gēdé):
- Huang-1 chip:
- A.V. 美少女戰士 Girl Fighting (A.V. Měi Shàonǚ Zhànshì)
- 餓狼伝説 Special (Garō Densetsu Special, original Gouder release only)
- Kart Fighter
- Somari the Adventurer (original Gouder and Kǎshèng releases)
- Huang-2 chip:
- A.V. 究極麻將 II (A.V. Jiūjí Májiàng, original Gouder release only)
This mapper can simulate three different ASICs: the Nintendo MMC1, MMC3 and Konami VRC2 (A0/A1, i.e. VRC2b). All three simulated chips have their separate registers, so that when switching between modes using the supervisor register, the entire mapper state changes including PRG/CHR ROM switchable and fixed banks as well as IRQ state.
Supervisor Register ($4100, write)
Mask: $C100 D~7654 3210 --------- .... .CMM |++- Mapper mode | 0: VRC2 | 1: MMC3 | 2: MMC1 | 3: same as 2 +--- Outer 256 KiB CHR-ROM bank (CHR A18)
Notes
- The Huang-2 chip differs from the Huang-1 chip in that the MMC1 PRG-ROM bank register is shifted by one bit to the left compared to what one would write to a normal MMC1, or to the Huang-1 in MMC1 mode. No submapper has been proposed yet for this behavior. In the meantime, the one game relying on this can be heuristically detected by having PRG-ROM and CHR-ROM sizes each of only 128 KiB.
- When switching to MMC1 mode, the serial shift register is reset. Garō Densetsu Special relies on this. Supposedly, only the -W configuration of the PAL actually does this, though no game seems to be adversely affected by always emulating this behavior.
- The VRC2 CHR-ROM registers are initialized on power-up to $FF. The original release of Somari the Adventurer relies on this.
- Garō Densetsu Special relies on being able to write to mirrors of $8xxx, $9xxx, and $Axxx in VRC2 mode.
- The Kǎshèng rerelease of Garō Densetsu Special uses INES Mapper 115 instead.
- The Kǎshèng rerelease of A.V. 究極麻將 II uses INES Mapper 115 instead.
Similar mappers
- INES Mapper 014 and INES Mapper 238 uses the same ASIC but with the PAL programmed differently to respond in other ways to other addresses.