User talk:Hamtaro126

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H126-ROM1 and H126-RAM1 mapper format (for next letter of ZZO38's Mapperset)

This mapper will be a DIY thing, I will not make carts, But it is possible to make them!

Based off a combo of UxROM and MMC3

PPU (H126-ROM1):

  • $0000-$03FF: 4k CHR bank 1 (uses $40C0)
  • $0400-$07FF: 4k CHR bank 2 (uses $40C1)
  • $0800-$0BFF: 4k CHR bank 3 (uses $40C2)
  • $0C00-$0FFF: 4k CHR bank 4 (uses $40C3)
  • $1000-$13FF: 4k CHR bank 5 (uses $40C4)
  • $1400-$17FF: 4k CHR bank 6 (uses $40C5)
  • $1800-$1BFF: 4k CHR bank 7 (uses $40C6)
  • $1C00-$1FFF: 4k CHR bank 8 (uses $40C7)

PPU (H126-RAM1):

  • $0000-$1FFF - 8k CHR RAM ($40C0-$40C7 are unused!)

RAM:

  • $5000-$5FFF: 2k WRAM (optional)
  • $6000-$7FFF: 8k SaveRAM or WRAM

Unused Extension (optional):

  • $40C8: Unused Extension

ROM:

  • $8000-$9FFF: 8k ROM bank 1 (uses $40C9)
  • $A000-$BFFF: 8k ROM bank 2 (uses $40CA)
  • $C000-$DFFF: 8k ROM bank 3 (uses $40CB)
  • $E000-$FFFF: 8k ROM bank 4 (Fixed)

IRQ (optional):

  • $40CC: Mirroring
  • $40CD: Control Disable
  • $40CE: Control Enable
  • $40CF: Cycle IRQ Counter Value (MMC5 style)

This is a WIP, May Change!!! --Hamtaro126 (talk) 08:10, 29 June 2013 (MDT)

Discussion

I suggest to use $40C8, $40C9, $40CA for the PRG ROM bank select, and having $40CB unused. I think this would be more logical and probably simpler to build. --Zzo38 (talk) 12:10, 29 June 2013 (MDT)
This is the very similar to Taito's X1-017. —Lidnariq (talk) 13:12, 29 June 2013 (MDT)