Apr 7, 2010 · First you'll want to implement the Namco 108 family (mapper 206 and friends) because it's simpler. Then you can add the extra MMC3 logic (mirroring switch, WRAM decoding, IRQ, etc.) once you have that working.

It's inspired by ultra cheap "COOLBOY" multicarts but instead of using single mapper (MMC3) "COOLGIRL" uses EPM1270T144 CPLD chip to simulate many different mappers. Both PRG and CHR data stored on a single flash memory chip.

Nov 4, 2024 · A lot of bootleg (pirate) cart reproductions were done using 74 and 40 families chips, because that was the only way to mimic the behavior of ASIC mappers like MMC1 or MMC3 at that time. This page shows some tricks and solutions for common problems during implementing logic using discrete circuits.

Mar 26, 2025 · The Nintendo MMC3 is a mapper ASIC used in Nintendo's TxROM Game Pak boards. Most common TxROM boards, along with the NES-HKROM board (which uses the Nintendo MMC6), are assigned to iNES Mapper 004. MMC3

Jan 5, 2023 · I'm wondering if there are any popular re-implementation of mapper chips, like MMC3 or MMC5 (or even MMC1) that are approachable for hobbyists. I'm interested in solutions that use PLA, CPLD, MCU (or even discrete 74LS00 logic) to implement common mappers. (Ideally with through hole components, but that's not a hard requirement.)

Sep 19, 2018 · MMC1 and MMC3 have both been recently duplicated in CPLD form by a few homebrew/repro manufacturers, but they cost more and there have been droughts of availability. MMC1 is particularly cranky to work with, from a coding perspective.

One of the few games using the MMC5 was Castlevanoa III: Dracula's Curse. But with the MMC1, MMC2 (PunchOut) and MMC3 mappers as well as some unlicensed mappers like the Color Dreams, the FunkyFlash cart was able to run a good share of the NES games available.

May 16, 2021 · Here’s a guide on how to populate my custom designed NES reproduction PCB that can make MMC1 or MMC3 games. This board supports most MMC1 games with the SxROM board name, as well as most MMC3 games with the TxROM board name (where the lowercase ‘x’ is a stand-in for other board types).

May 30, 2021 · Seeing how most modern mmc3 homebrew pcbs use a cpld you could easily program one to function similar to the mmc3 but with expanded memory capabilities. Because mmc3 only looks at the lower 6 bits when selecting a prg bank, you will need to add additional registers to control the expanded memory.

Jul 11, 2020 · I started to write my first MMC3 based on CPLD (verilog). The 1st requirement is just implement the Bank Select for only PRG ROM (Game and sound can run without correct graphic). But after multil times checked and changed verilog code, my mmc3 not work yet = ((