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The Commodore 64 (also referred to as "C64" for brevity) is a home computer released in January 1982 by Commodore Business Machines and retired in April 1994. The machine mounts the MOS Technology 6510 or the MOS Technology 6800, variants of the famous 6502 CPU, running at 1.023 MHz for NTSC models and at 0.985 MHz for PAL models. It runs a built-in version of the Commodore KERNAL operating system and is operated through Commodore BASIC V2.0, a variant of the Microsoft BASIC programming language.

The C64 had an integrated keyboard, but did not come with a monitor, a cassette tape deck, a floppy disk drive, a joystick or a mouse, although all of these were separately available both from Commodore and from third-party manufacturers and, except for the display, were not necessary for some software.

The computer had a huge success among businesses, video gamers and software developers and remains today the best-selling computer model of all time.

A "breadbin" Commodore 64.

Commodore models[]

"Breadbin" C64[]

The Commodore 64 initially used a case reminiscent of that of the previous Commodore VIC-20, with the only major external changes being the tan colour and the labels. This design is usually nicknamed "breadbin".

Educator 64[]

Main article: Commodore Educator 64

The Commodore Educator 64 is a C64 variant released from 1983 for use in schools. It came inside a Commodore PET case to avoid vandalism and thefts and used a built-in "greenscale" monochrome monitor.


Main article: Commodore SX-64

Also in 1984, Commodore released a portable version of the C64, known as "SX-64" or "Executive 64" or, in Europe, as "VIP-64", which features a five-inches built-in color monitor, a built-in Commodore 1541 floppy disk drive and a handle doubling as a stand for the computer. The system, which was the first full-color portable computer, follows the then-standard "luggable" portable computer format, which was later replaced by the "laptop" format.


In 1986, Commodore released the Commodore 64C (C64C) computer, which was functionally identical to the original, but whose exterior design was remodeled in the sleeker style of the Commodore 128 and other contemporary design trends. The modifications to the C64 line were more than skin deep in the C64C with new versions of the SID, VIC and I/O chips being deployed--with the core voltage reduced from 12v to 9v. In the United States, the C64C was often bundled with the third-party GEOS GUI-based operating system. The Commodore 1541 disk drive received a matching face-lift resulting in the 1541c. Later a smaller, sleeker 1541-II model was introduced along with the 800 KB 3.5-inch capable 1581.


The Commodore 64 Games System is a modified version of the C64 with a modified motherboard allowing for cartridges to be loaded from the top of the system, a modified ROM which does not instantly boot into BASIC, but rather shows a screen prompting the user to shut down the system and insert a cartridge, no keyboard and a new case and joystick design. The system was essentially a C64-compatible games console, released in 1990 for the European market, but its obsoleteness, its lack of new features when compared to a standard C64 or to competitor consoles and the impossibility to use the keyboard and the peripheral ports made it a market failure.


Operating systems[]


Main article: KERNAL

The KERNAL is the primary built-in operating system of the C64. It is the same OS previously mounted on Commodore PET, CMB-II and VIC-20 machines, and runs directly from the ROM. It is not accessed directly since it has no user interface, but rather through BASIC or some other form of interpreter, most usefully machine code and assembly language monitors.

Commodore DOS[]

Main article: Commodore DOS

Although it does not properly run on the computer, C64s interact with the Commodore DOS operating system built inside the floppy disk drives each time they operate them.


GEOS was initially released for the C64, and was usually bundled with C64C machines.


Main article: CP/M

A specific version of CP/M was also relased for the C64 on a special cartridge, although the system was accessed by using a 5 1/4-inch boot floppy disk. The cartridge contained a Zilog Z80 co-processor allowing compatibility with the code. Such product was probably produced by the OS's mother comany, Digital Research, Inc..

External Links[]

List of Commodore micromputers
6502-based 8-Bit Kim-1 - Vic-20 - PET - CBM-II - C64 -

SX-64 -C16\C116 - Plus /4 - C128\C128D - Commodore 65

68000-based 16\32-bit Amiga 1000 - Amiga 500 - Amiga 2000 (Amiga 2500) - Amiga 1500 - CDTV - CD32 - Amiga 3000 - (Amiga 3000UX - Amiga 3000T) - Amiga 500+ - Amiga 600 - Amiga 1200 - Amiga 4000 - 4000T
Other Commodore 900 - PC Compatible systems