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:
7 bit 0 --------- .... PPPP |||| ++++- Select 8 KB PRG ROM at $8000
7 bit 0 --------- .... PPPP |||| ++++- Select 8 KB PRG ROM at $A000
7 bit 0 --------- .... PPPP |||| ++++- Select 8 KB PRG ROM at $C000
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.
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.
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.
Categories: ASIC mappers, In NesCartDB