Color Dreams: Difference between revisions
m (move Disch's notes from iNES Mapper 011) |
Rainwarrior (talk | contribs) m (→Emulator oversize support: linking oversize) |
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$8000-FFFF: [PPPP PPPP] | $8000-FFFF: [PPPP PPPP] | ||
[CCCC ....] | [CCCC ....] | ||
''See also:'' [[Oversize]] | |||
== Sources == | == Sources == | ||
*[http://kevtris.org/mappers/cdreams/index.html Color Dreams doc by Kevin Horton] | *[http://kevtris.org/mappers/cdreams/index.html Color Dreams doc by Kevin Horton] |
Revision as of 01:24, 4 October 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.
Disch's Notes
Here are Disch's original notes: ======================== = Mapper 011 = ======================== Example Games: -------------------------- Crystal Mines Metal Fighter Notes: -------------------------- This mapper suffers from bus conflicts! Registers **BUS CONFLICTS**: -------------------------- $8000-FFFF: [CCCC LLPP] P = Select 32k PRG page @ $8000-FFFF L = Lockout defeat usage C = Select 8k CHR page @ $0000-1FFF Lockout defeat: -------------------------- I have no idea how this works. Kevtris page makes mention of it. From an emulation standpoint, it's not all that important.
Emulator oversize support
FCEUX's implementation:
$8000-FFFF: [CCCC PPPP]
Nestopia's implementation:
$8000-FFFF: [PPPP PPPP] [CCCC ....]
See also: Oversize