MOS Technology · 1975
MOS Technology 6502
The 8-bit processor that democratised personal computing
Year
1975
Architecture
8-bit
Clock
1–3 MHz
Transistors
~3,510
Price (1975)
$25
Found in
Apple I, II · C64 · NES
The 8-bit processor that democratised personal computing
In 1975, microprocessors cost hundreds of dollars — out of reach for anyone outside a large corporation. Chuck Peddle and his team at MOS Technology had a bold idea: build a chip compatible with the Motorola 6800 but sell it for just $25, less than a tenth of the competition.
The 6502 was unveiled at the WESCON 1975 show in San Francisco and caused a sensation. Engineers from competing companies initially assumed it was defective — it simply could not cost that little and actually work.
The 6502 became the heart of the Apple I and Apple II, the Commodore 64, the Nintendo NES, and the Atari 2600. Without it, the personal computer revolution of the 1970s and '80s would have taken a completely different shape and timeline.
Steve Wozniak chose the 6502 for the Apple I precisely because of its price: he could afford to buy one with his own savings. A cheap CPU that democratised computing.
A modified version of the 6502, the 2A03, beat at the heart of the Nintendo NES — the console that saved the video game industry after the crash of 1983. Variants of the 6502 are still manufactured and used in embedded systems today. An architectural core that has survived fifty years.
I remember opening my Commodore 64, looking inside at the logic board and thinking wooow! It's amazing. All these chips put in place in such a precise way. I spent minutes looking at the microprocessor, MOS 6502, and tried figuring out with my fantasy what kind of magic happened inside every time I used the computer. The truth is that I had no idea. But the reality — I discovered many years later during my studies — was shocking: only six 8-bit registers, a simple ALU not capable of multiplication and division. That's all! 🤯
Are you curious to find out more about how this microprocessor works? This video is for you.