Color Dreams

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Color Dreams
Company Color Dreams/Wisdom Tree
Boards COLORDREAMS
PRG ROM capacity 128K
PRG ROM window 32K
PRG RAM capacity None
CHR capacity 128K
CHR window 8k
Nametable mirroring Fixed H or V, controlled by solder pads
Bus conflicts Yes
IRQ No
Audio No
iNES mappers 011
NESCartDB
iNES 011

The Color Dreams Mapper was a mapper used by the Color Dreams company. The iNES format assigns mapper 11 to these boards.

The mapper is a board with discrete logic that provides up to four 32 KB banks of PRG ROM, up to sixteen 8 KB banks of CHR ROM, and controls a charge pump to defeat the CIC lockout chip.

Color Dreams was a company that developed and published unlicensed NES games. They also operated with the alternate labels Wisdom Tree which produced games with Christianity themes (primarily sold in Christian bookstores), and Bunch Games which produced lower budget games. American Game Cartridges also used the Color Dreams mapper for their port of Exidy's Chiller.

Example games:

  • Bible Adventures
  • Chiller
  • Crystal Mines
  • Menace Beach
  • Metal Fighter

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.

The lockout defeat is not necessary for emulator implementation. See references below for more information.

Variants

Nintendo's own GxROM family of boards is nearly identical in function to the Color Dreams board.

A multicart mapper based on this mapper is iNES Mapper 046, with an outer bank register at $6000-$7FFF.

Some variations of this board/mapper (e.g the one used in the prototype game "Free Fall") appear to be free of bus conflicts and will not work properly if bus conflicts are emulated.

References