Motorola

MOS Technologies was originally started as a supplier of electronic calculator parts. Their involvement with microprocessors would begin when Motorola engineers defected to MOS in the 1970s and began work on on the 650 series of microprocessors to compete with the Motorola 6800 series.

MOS should not be confused with Motorola.

MOS would eventually be purchased by Commodore Business Machines in 1976 where the MOS 650 series would be put to good use in powering their products, such as the MOS 6502 in the Commodore PET, Commodore VIC-20, and the Commodore 1541 floppy disk drive as well as the MOS 6510 in the Commodore 64.

Commodore, through their MOS subsidiary, was also a major microprocessor supplier for the video game industry in the early 1980s, providing CPUs and other important components to various video game hardware manufacturers such as Atari, Mattel, and Coleco for the 2600 VCS, Intellivision, and Colecovision, respectively. This precipitated an aggressive shakeout of the home video game market when Commodore would begin to sell their personal computers in direct competition against home video game consoles that had to use Commodore technology in their manufacture, which was a significant factor that helped to pave the way for the great video game crash.

Even after the video game crash, Commodore's presence in the video game business would exist though the Ricoh 2A03 (NTSC) and 2A07 CPUs for use in the Famicom/NES, which were derived from the MOS 6502. Indeed, in the Super Nintendo/Super Famicom, the Ricoh 5A22 CPU was derived from the Western Design Center 65C816 which itself was derived from and is compatible with the MOS 6502.