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 | 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.