Color Dreams: Difference between revisions
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== Variants == | == Variants == | ||
Nintendo's own [[GxROM]] family of boards is nearly identical in function to the Color Dreams board. | Nintendo's own [[GxROM]] family of boards is nearly identical in function to the Color Dreams board. | ||
== Sources == | |||
*[http://kevtris.org/mappers/cdreams/index.html Color Dreams doc by Kevin Horton] |
Revision as of 15:58, 3 March 2012
Color Dreams was a company that developed and published unlicensed NES games. The later Color Dreams games were Christianity-themed games, published under the Wisdom Tree label and sold through Christian bookstores.
Color Dreams games used a board with a discrete logic mapper that provide up to four 32 KB banks of PRG ROM and up to sixteen 8 KB banks of CHR ROM and controls a charge pump to defeat the CIC lockout chip. The iNES format assigns mapper 11 to these boards.
Overview
- PRG ROM size: Up to 128 KB
- PRG ROM bank size: 32 KB
- PRG RAM: None
- CHR capacity: Up to 128 KB ROM
- CHR bank size: 8 KB
- Nametable mirroring: Solder pads select vertical or horizontal mirroring
- Subject to bus conflicts: Yes
Banks
- CPU $8000-$FFFF: 32 KB switchable PRG ROM bank
- PPU $0000-$1FFF: 8 KB switchable CHR ROM bank
Registers
Bank select ($8000-$FFFF)
7 bit 0 ---- ---- CCCC LLPP |||| |||| |||| ||++- Select 32 KB PRG ROM bank for CPU $8000-$FFFF |||| ++--- Used for lockout defeat ++++------ Select 8 KB CHR ROM bank for PPU $0000-$1FFF
Hardware
The Color Dreams board contains a 74LS377 octal D latch (8-bit register) to select the current PRG and CHR banks.
Variants
Nintendo's own GxROM family of boards is nearly identical in function to the Color Dreams board.