banks, and character ROM to be switched in 1KB banks. This MMC has two known revisions: VRC2a and VRC2b. VRC3 Manufacturer: Konami Games: SalamanderJP Exclusively used in the Japanese version of Salamander. VRC4 Manufacturer: Konami Games: Gradius IIJP, Crisis Force, Bio Miracle:Boku tte Upa, Ganbare Goemon Gaiden 2, WaiWai World, WaiWai World 2, Twinbee 3 The VRC4 Chip is similar to the VRC2 chip, other than the VRC4 allowing for 512KB CHR capacity, 2 8KB PRG ROM banking modes and 1 screen mirroring. VRC5 Manufacturer: Konami Games: Space SchoolJP Exclusively used in the QTa adapter in Konami's Space School series of educational games. VRC6 Manufacturer: Konami Games: Akumajō Densetsu, Mōryō Senki MADARA, Esper Dream II The VRC6 (Virtual Rom Controller) is an advanced MMC chip from Konami, supporting bank switching for both program code and graphics as well as a CPU cycle–based IRQ counter, which can also act as a scanline counter. The chip also contains support for three extra sound channels (two square waves of eight duty cycles each, and one sawtooth wave). It is used in Akumajō Densetsu (the Japanese version of Castlevania III: Dracula's Curse), while the Western version uses the MMC5 from Nintendo. Since the Nintendo Entertainment System does not allow cartridges to add additional sound channels, the Famicom version's soundtrack was reworked to follow those specifications; thus the soundtrack on the Western version is implemented by the five sound channels built into the stock NES. VRC7 Manufacturer: Konami, Yamaha Games: Lagrange Point, Tiny Toon Adventures 2: Trouble in Wackyland The VRC7 is an advanced MMC chip from Konami, supporting bank switching and IRQ counting equivalent to the VRC6, and containing a YM2413 derivative providing 6 channels of FM Synthesis audio. This advanced audio is used only in the Famicom game Lagrange Point. The Japanese version of Tiny Toon Adventures 2 uses the VRC7 but not the extended audio. Namco 163 Manufacturer: Namco Games: Erika to Satoru no Yume Bōken, Final Lap, King of Kings, Mappy Kids, Digital Devil Story: Megami Tensei II, Namco Classic II, Romance of the Three Kingdoms, Romance of the Three Kingdoms II, Yokai Dochuki, Rolling ThunderJP, Top Striker The 163 has been only used in games exclusive to Japan. Its capabilities were a little better than Nintendo's MMC3. A variant contained extra sound hardware that plays 4-bit wave samples. It supports 1 to 8 extra sound channels, but audible aliasing appears