[[Category:SPO600]][[Category:Computer Architecture]][[Category:Assembly Language]][[Image:MOS_6502_1.jpg|thumb|400px|right|The MOS 6502 processor. Image credit: Christian Bassow - [https://creativecommons.org/licenses/by-sa/4.0) CC-BY-SA 4.0] ]]The MOS Technologies 6502 processor was introduced in the mid-1970s to fill the need for a affordable general-purpose CPU. Its low cost (US$25 at introduction, less than C$0.89 now) was less than one-sixth of competing CPUs, and it had very simple circuitry requirements which made it simple and inexpensive to incorporate it into products. It was therefore used in many home and personal computers, such as the Apple II; the Commodore PET, Vic-20, and C64; the Atari 400 and 800; the BBC Micro; and games such as the Nintendo Entertainment System (NES). A number of variations of this processor have been produced, using different semiconductor processes, integrated peripherals, instruction and data-width extensions, and pinouts.