Commodore used two different chips as the Commodore 64 CPU during its long lifetime. Both Commodore 64 CPUs were proprietary derivatives of the venerable MOS 6502, but unlike the 6502, Commodore and its MOS subsidiary never licensed either of them to other sources.
Like the Atari 2600 CPU, the 6510 and 8500 were 6502s with some changes. Unlike the 6507, the 6510/8500 added capability, rather than removing it.
David Farquhar is a computer security professional, entrepreneur, and author. He has written professionally about computers since 1991, so he was writing about retro computers when they were still new. He has been working in IT professionally since 1994 and has specialized in vulnerability management since 2013. He holds Security+ and CISSP certifications. Today he blogs five times a week, mostly about retro computers and retro gaming covering the time period from 1975 to 2000.
