VRC1: Difference between revisions
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m (Created page with '== Overview == * PRG ROM bank size: 8 KB at $8000, $A000, and $C000 * PRG RAM: Unknown (none?) * CHR bank size: 4 KB * Nametable mirroring: Controlled by mapper * Subject to ...') |
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== Overview == | == Overview == | ||
* Manufacturer: Konami | |||
* PRG ROM bank size: 8 KB at $8000, $A000, and $C000 | * PRG ROM bank size: 8 KB at $8000, $A000, and $C000 | ||
* PRG RAM: Unknown (none?) | * PRG RAM: Unknown (none?) | ||
| Line 5: | Line 6: | ||
* Nametable [[mirroring]]: Controlled by mapper | * Nametable [[mirroring]]: Controlled by mapper | ||
* Subject to [[bus conflict]]s: No | * Subject to [[bus conflict]]s: No | ||
== Registers == | == Registers == | ||
Revision as of 12:29, 12 June 2009
Overview
- Manufacturer: Konami
- PRG ROM bank size: 8 KB at $8000, $A000, and $C000
- PRG RAM: Unknown (none?)
- CHR bank size: 4 KB
- Nametable mirroring: Controlled by mapper
- Subject to bus conflicts: No
Registers
PRG Select 0 ($8000-$8FFF)
7 bit 0
---------
.... PPPP
||||
++++- Select 8 KB PRG ROM at $8000
PRG Select 0 ($A000-$AFFF)
7 bit 0
---------
.... PPPP
||||
++++- Select 8 KB PRG ROM at $A000
PRG Select 0 ($C000-$CFFF)
7 bit 0
---------
.... PPPP
||||
++++- Select 8 KB PRG ROM at $C000
Mirroring Control, CHR bits ($9000-$9FFF)
7 bit 0
---------
.... .BAM
|||
||+- Mirroring (0: Vertical; 1: Horizontal)
|+-- High Bit of 4 KB CHR bank at PPU $0000
+--- High Bit of 4 KB CHR bank at PPU $1000
CHR Select 0 ($E000-$EFFF)
7 bit 0
---------
.... CCCC
||||
++++- Low 4 bits of 4 KB CHR bank at PPU $0000
These bits combined with bit 1 of $9000 make a 5-bit CHR selection.
CHR Select 1 ($F000-$FFFF)
7 bit 0
---------
.... CCCC
||||
++++- Low 4 bits of 4 KB CHR bank at PPU $1000
These bits combined with bit 2 of $9000 make a 5-bit CHR selection.
