Commodore 64

From Video Game Music Preservation Foundation Wiki
Revision as of 07:10, 9 September 2019 by Professor Chaos (talk | contribs)
Jump to: navigation, search
Platform - C64.png
Commodore 64
Commodore 64.jpg
Released: 1982-08-??
Discontinued: 1994-04-??
Developer: Commodore
Type: Hardware

The Commodore 64 is a home computer released by Commodore and the best-selling single model of personal computer in history. Unlike modern computers which boot into an operating system, the Commodore 64 boots into Commodore BASIC, a primitive programming language which used little memory, but also was way too slow to do much.

Software was either typed in BASIC or loaded through peripheral devices like disk drives, cassette drives, or ROM cartridges. However, even the standard loaders were so slow that many people and companies developed and acquired fast loaders. Tape loaders were still slowed down by hardware, but made up for the waiting time by playing music, which is still fondly remembered in the UK, where disk drives were especially expensive. Disk loaders could be much faster, though even more so when blanking the screen and not playing music, which many did.



Music and Sound

The Commodore 64 had a built-in SID chip. The chip is clocked at the same frequency as the CPU (1022727 Hz on NTSC machines and 985248 Hz on PAL machines). However, most sound drivers are clocked at the screen refresh rate (50.125 Hz on PAL, 59.826 Hz on NTSC) to avoid interruptions through the video chip. On the wrong region's machine, pitch is off by 65 cents and speed by up to 19%. The speed difference can even worsen bugs in the SID chip's envelope, which in turn mutes notes. When porting to another region, frequencies and durations are ideally to be converted, although, if anything, many programmers simply postponed one driver call out of 5.

Also Sound Expander and Voice Master were produced for this platform, but they were supported too poorly.


In the 1980s, composers usually wrote their own drivers in BASIC or assembly language and typed the notes as numbers. Although there have been editors which allowed their music to be embedded into other programs as early as 1983 (most notably, Master Composer), they were often too limited and bloated for games until 1987.