MOS Technology

MOS Technology, Inc was a microprocessor manufacturing company most famous for its creation of the 6502 processor.

The 6502 was used as the main CPU in many computers and game consoles during the late 1970s and early-to-mid-1980s. An incomplete list of machines that were built around the 6502 include:

Home computers
Acorn Electron/BBC Microcomputer
Apple II
Commodore PET
Commodore VIC-20
Commodore 64

Game consoles
Atari 2600
Nintendo Entertainment System or NES

Company History

The company's original target market and purpose was to provide a second source for Texas Instruments designed electronic calculators and the chips inside them.

Fortunes for the company changed dramatically in 1975. Several designers from Motorola left the company shortly after the release of the Motorola 6800 processor. MOS was a small firm with good credentials in the right area, the East coast of the USA.

The team of four design engineers was headed by Chuck Peddle and included Bill Mensch. At MOS they set about building a new CPU that would outperform the 6800 while being similar to it in purpose. The resulting 6501 design was somewhat similar to the 6800, but by using several simplifications in the design, the 6501 would be up to four times faster.