NES 2.0 Mapper 285: Difference between revisions
From NESdev Wiki
Jump to navigationJump to search
NewRisingSun (talk | contribs) (Disambiguate two incompatible mappers that had unfortunately been assigned to the same UNIF MAPR.) |
NewRisingSun (talk | contribs) mNo edit summary |
||
| Line 1: | Line 1: | ||
{{DEFAULTSORT: | {{DEFAULTSORT:285}}[[Category:Multicart mappers]][[Category:Mappers with CHR RAM]]'''NES 2.0 Mapper 285''' is used for the ''A65AS'' and ''JY-066'' multicarts. The UNIF board name for both incompatible variants is '''BMC-A65AS'''. | ||
=Banks= | =Banks= | ||
Latest revision as of 14:16, 17 February 2024
NES 2.0 Mapper 285 is used for the A65AS and JY-066 multicarts. The UNIF board name for both incompatible variants is BMC-A65AS.
Banks
- CPU $8000-$BFFF: In 16 KiB mode: 16 KiB switchable inner bank, 128 KiB switchable outer bank
- CPU $C000-$FFFF: In 16 KiB mode: 16 KiB fixed inner bank 7, 128 KiB switchable outer bank
- CPU $8000-$FFFF: In 32 KiB mode: 32 KiB switchable bank
- PPU $0000-$1FFF: 8 KiB unbanked CHR-RAM
Data Latch (CPU $8000-$FFFF)
A65AS (Submapper 0)
Bit 7654 3210
---------
SPMO OBBB
|||| |+++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF in 16 KiB mode (bit 6=0)
|||| |++-- Select 32 KiB PRG-ROM bank at CPU $8000-$FFFF in 32 KiB mode (bit 6=1)
|||+-+---- Select 128 KiB outer PRG-ROM bank at CPU $8000-$FFFF in 16 KiB mode (bit 6=0)
||+------- Select nametable mirroring
|| 0: Vertical (bit 7=0)/Single-screen, page 0 (bit 7=1)
|| 1: Horizontal (bit 7=0)/Single-screen, page 1 (bit 7=1)
|+-------- Select PRG banking mode
| 0: 16 KiB
| 1: 32 KiB
+--------- Select nametable mirroring type
0: Horizontal/vertical (selected via bit 3)
1: Single-screen (selected via bit 5)
JY-066 (Submapper 1)
Bit 7654 3210
---------
SPMO HBBB
|||| |+++- Select 16 KiB inner PRG-ROM bank at CPU $8000-$BFFF in 16 KiB mode (bit 6=0)
|||| |++-- Select 32 KiB PRG-ROM bank at CPU $8000-$FFFF in 32 KiB mode (bit 6=1)
|||| +---- Select nametable mirroring if bit 7=0
|||| 0: Vertical
|||| 1: Horizontal
||++------ Select 128 KiB outer PRG-ROM bank at CPU $8000-$FFFF in 16 KiB mode (bit 6=0)
||+------- Select nametable mirroring if bit 7=1
|| 0: Single-screen, page 0
|| 1: Single-screen, page 1
|+-------- Select PRG banking mode
| 0: 16 KiB
| 1: 32 KiB
+--------- Select nametable mirroring type
0: Horizontal/vertical (selected via bit 3)
1: Single-screen (selected via bit 5)
