VRC1: Difference between revisions
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{{Infobox_iNES_mapper | |||
|name=VRC1 | |||
|company=Konami | |||
|mapper=75 | |||
|nescartdbgames=6 | |||
|complexity=ASIC | |||
|boards=JF-20, JF-22, 4036, 302114A, 350459 | |||
|pinout=VRC1 pinout | |||
|prgmax=128K | |||
|prgpage=8K | |||
|wrammax=none | |||
|wrampage=n/a | |||
|chrmax=128K | |||
|chrpage=4K | |||
|mirroring=H or V, switchable | |||
|busconflicts=No | |||
|irq=No | |||
}} | |||
[[Category:ASIC mappers]][[Category:in NesCartDB]] | [[Category:ASIC mappers]][[Category:in NesCartDB]] | ||
The Konami VRC1 is an [[:Category:ASIC mappers|ASIC]] [[MMC|mapper]]. The [[iNES]] format assigns '''mapper 75''' to VRC1. | The Konami VRC1 is an [[:Category:ASIC mappers|ASIC]] [[MMC|mapper]]. The [[iNES]] format assigns '''mapper 75''' to VRC1. | ||
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__TOC__ | __TOC__ | ||
== Banks == | == Banks == | ||
Latest revision as of 16:29, 26 January 2019
VRC1
| Company | Konami |
| Games | 6 in NesCartDB |
| Complexity | ASIC |
| Boards | JF-20, JF-22, 4036, 302114A, 350459 |
| Pinout | VRC1 pinout |
| PRG ROM capacity | 128K |
| PRG ROM window | 8K |
| PRG RAM capacity | none |
| PRG RAM window | n/a |
| CHR capacity | 128K |
| CHR window | 4K |
| Nametable mirroring | H or V, switchable |
| Bus conflicts | No |
| IRQ | No |
| Audio | No |
| iNES mappers | 075 |
The Konami VRC1 is an ASIC mapper. The iNES format assigns mapper 75 to VRC1.
The VRC1 was used in several Famicom games released by Konami and Jaleco:
- Exciting Boxing
- Ganbare Goemon! Karakuri Douchuu
- Jajamaru Ninpouchou
- King Kong 2: Ikari no Megaton Punch
- Moero!! Junior Basket: Two on Two
- Tetsuwan Atom
Banks
- CPU $8000-$9FFF: 8 KiB switchable PRG ROM bank
- CPU $A000-$BFFF: 8 KiB switchable PRG ROM bank
- CPU $C000-$DFFF: 8 KiB switchable PRG ROM bank
- CPU $E000-$FFFF: 8 KiB PRG ROM bank, fixed to the last bank
- PPU $0000-$0FFF: 4 KiB switchable CHR bank
- PPU $1000-$1FFF: 4 KiB switchable CHR bank
Registers
PRG Select 0 ($8000-$8FFF)
7 bit 0
---------
.... PPPP
||||
++++- Select 8 KB PRG ROM at $8000
PRG Select 1 ($A000-$AFFF)
7 bit 0
---------
.... PPPP
||||
++++- Select 8 KB PRG ROM at $A000
PRG Select 2 ($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 $1000
The mirroring bit is ignored if the cartridge is wired for 4-screen VRAM, as is typical for Vs. System games using the VRC1.
CHR Select 0 ($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.
