Color Dreams

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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.

Sources