when a sufficiently large number of channels are enabled. FME-7 Manufacturer: Sunsoft Games: Batman: Return of the Joker, Hebereke, and more. The FME-7 is a memory mapping circuit developed by Sunsoft for use in NES and Famicom cartridges. It switches program ROM in 8KB banks and switches the character ROM 1KB banks. It also contains hardware to generate IRQ signals after a specified number of CPU clock cycles, thus achieving split-screen effects with minimal use of processing power. SUNSOFT-4 Manufacturer: Sunsoft SUNSOFT 5B Manufacturer: Sunsoft Games: Gimmick! This version of the FME-7 contains a version of the widely used Yamaha YM2149. Unlicensed MMCs Some individual (homebrew) and unlicensed developers have made custom MMCs for the NES, most of which simply expand the available memory. 228 Manufacturer: Active Enterprises Games: Action 52, Cheetahmen II 228 is a simple bank switching MMC developed for use in the games Action 52 and Cheetahmen II. It does not have a nametable control bit. In the Action 52 multicart, it also contains a small 16-bit register area that contains the old menu selection when exiting a game. GTROM Manufacturer: Membler Industries GTROM or Cheapocadabra is a self-flashable MMC developed in 2015 for the homebrew market. The board contains 512K of PRG ROM, 16K of CHR ROM, and two LEDs. While the GTROM does not contain PRG RAM, saved games are possible due to PRG ROM being flashable by NES software. See also List of Super NES enhancement chips References Integrated circuits Memory management