NES 2.0 Mapper 340: Difference between revisions

From NESdev Wiki
Jump to navigationJump to search
No edit summary
Line 12: Line 12:
  A~FEDC BA98 7654 3210  D~7654 3210
  A~FEDC BA98 7654 3210  D~7654 3210
   -------------------    ---- ----
   -------------------    ---- ----
   .... .... ..MO OmIm     .... .III
   .... .... ..MO OIII     .... .III
               || || |          +++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF in UNROM mode
               || ||||          +++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF in UNROM mode
               || |+++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF/$C000-$FFFF in NROM-128 mode
               || |+++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF/$C000-$FFFF in NROM-128 mode
               |+-+|-|- Select 128 KiB outer PRG-ROM bank at CPU $8000-$FFFF
               |+-+|-|- Select 128 KiB outer PRG-ROM bank at CPU $8000-$FFFF

Revision as of 20:10, 6 April 2019

NES 2.0 mapper 340 is used for a 35-in-1 multicart. Its UNIF board name is BMC-K-3036.

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/Mirror of $8000-$BFFF and switchable 128 KiB outer PRG-ROM bank
  • PPU $0000-$1FFF: Unbanked 8 KiB CHR-RAM

Address/Data Latch ($8000-$FFFF)

Mask: $8000

A~FEDC BA98 7654 3210   D~7654 3210
  -------------------     ---- ----
  .... .... ..MO OIII     .... .III
              || ||||           +++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF in UNROM mode
              || |+++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF/$C000-$FFFF in NROM-128 mode
              |+-+|-|- Select 128 KiB outer PRG-ROM bank at CPU $8000-$FFFF
              +---|-|- Select $C000-$FFFF behavior
              |   | |   0: UNROM (Inner Bank forced to #7 at CPU $C000-$FFFF)
              |   | |   1: NROM-128 (CPU $C000-$FFFF mirror of $8000-$BFFF)
              +---+-+- Select nametable mirroring type
                        0x25: Horizontal
                        all others: Vertical