MOS Technology 6502
The MOS 6502 is an 8-bit processor that was originally developed by a team led by the engineer Chuck Peddle. It was introduced in 1975 and it is still being produced. It was produced by the following companies.
- California Micro Devices (GTE Microcircuits)
- Commodore Semiconductor Group (MOS Technology)
- Rockwell
- Synertek
- Western Design Center
Currently it is only produced by Western Design Center (WDC)
It was a popular choice of processor because of its low price and high capabilities. It was used in multiple early computers such as the Commodore 64, Commodore VIC-20, Apple II, BBC micro, and many others.
Internals
The 6502 had many revisions and derivatives. Most of the revisions have either enhanced its capabilities or have added new features.
Depending on the manufacturer, the fabrication process can be CMOS, HMOS and NMOS.
The 6502 has three registers, one main register and two index registers. The original MOS 6502 had 151 "legal" opcodes. Later version included more.
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