NES 2.0 Mapper 295: Difference between revisions

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Its UNIF board name is '''BMC-13in1JY110''', although FCEUX' support is non-working.
Its UNIF board name is '''BMC-13in1JY110''', although FCEUX' support is non-working.


The same bits in register $D003 selects both PRG and CHR outer banks, and extended nametable mirroring is selected via bit 3 of $D001. It is almost identical to [[NES 2.0 Mapper 281]], except that the outer bank size is 128 KiB rather than 256 KiB.
The same bits in register $D003 select both PRG and CHR outer banks, and extended nametable mirroring is selected via bit 3 of $D001. It is almost identical to [[NES 2.0 Mapper 281]], except that the outer bank size is 128 KiB rather than 256 KiB.


=Registers=
=Registers=

Revision as of 14:55, 13 March 2018

NES 2.0 Mapper 295 is used for several multicarts from J.Y. Company:

  • 1996 Soccer 7-in-1 (JY-014B)
  • 1997 Super HIK 4-in-1 (JY-095)
  • 1997 Super HIK 7-in-1 (JY-096)
  • 1997 Super HIK 4-in-1 (JY-099)
  • 1997 Super 9-in-1 (JY-109)
  • 1997 Super 13-in-1 (JY-110)

Its UNIF board name is BMC-13in1JY110, although FCEUX' support is non-working.

The same bits in register $D003 select both PRG and CHR outer banks, and extended nametable mirroring is selected via bit 3 of $D001. It is almost identical to NES 2.0 Mapper 281, except that the outer bank size is 128 KiB rather than 256 KiB.

Registers

$8000-$D000, $D002: As Mapper 90.

Nametable Mirroring Control Register ($D001)

Mask: $F003

7654 3210
---- ----
.... E.MM
     | ++- Select nametable mirroring if bit 3==0
     |     0: Vertical
     |     1: Horizontal
     |     2: One-screen page 0
     |     3: One-screen page 1
     +---- Select extended nametable mirroring
           0: Disabled, use $D001 bits 0-1
           1: Enabled, use $B000-$B007

Outer Bank Register ($D003)

Mask: $F003

7654 3210
---- ----
.... .CCC
      +++- Select 128 KiB outer PRG-ROM bank
      +++- Select 128 KiB outer CHR-ROM bank

Notes

  • PRG ($8000-$8FFF) and CHR ($9000-$AFFF) bank select register bits that select 128 KiB banks are masked off.
  • JY-109 and JY-110 use 8 KiB of unbanked CHR-RAM rather than CHR-ROM. Simply assume CHR-RAM if no CHR-ROM banks are present in the ROM image.