The Commodore 64, introduced in 1982, became the best-selling single computer model ever made, selling in the tens of millions over its long production life. Built around the MOS Technology 6510, a variant of the 6502 with an on-chip I/O port, the machine paired a capable 8-bit processor with 64 kilobytes of RAM and two custom chips that set it apart from rivals at its price: the VIC-II video chip and the SID sound chip, both designed by Commodore’s in-house MOS engineers.
The Commodore 64 Programmer’s Reference Guide, the company’s official technical manual, documents these chips in detail. It describes the VIC-II’s hardware sprites, programmable movable objects that the video chip composites onto the display without the processor having to redraw them, along with the machine’s character and bitmap graphics modes and color handling. The same guide documents the SID chip’s three independent voices, multiple waveforms, filtering, and envelope control, an unusually rich synthesizer for a home computer of the time.
Those two chips shaped the machine’s culture. The SID’s expressive synthesis gave rise to a distinctive body of chiptune music, with composers writing directly to the chip’s registers to coax remarkably complex pieces from three voices. The VIC-II’s sprites and color tricks, combined with the documented hardware in the Reference Guide, gave game programmers and demo coders a well-understood platform to push to its limits, and the Commodore 64 became one of the central machines of the early demoscene.
Commodore’s ownership of MOS Technology let it manufacture the 64’s custom chips and processor in-house, which kept costs low and allowed Jack Tramiel’s company to price the machine aggressively. That pricing, and Commodore’s willingness to sell through mass-market retail channels rather than computer specialty stores alone, helped the 64 reach an enormous audience of ordinary buyers, fulfilling Commodore’s ambition of computers for the masses.
The Commodore 64 came with Commodore BASIC built into ROM, so that switching it on dropped the user straight into a programming environment. For a generation of users it was a first computer and a first taste of writing code, of game development, and of low-level hardware programming. Its combination of mass-market sales, documented custom hardware, and an active community made it one of the most influential personal computers in history.