Commodore VIC-20

3 years after release of PET, Commodore understood that their computer was too expensive to become popular. Designed as home computer, VIC-20 was cheap (later it was made cheaper by using less, but more specialized chips) and enough for home/gaming applications. In 1982 it was the best selling coputer of the year.
Sales slowed down in 1983 and later, as Commodore released Commodore 64 microcomputer with bigger memory, SID sound chip and better graphics modes. VIC-20 was discontinued in 1985.

There's a strange story about introducing it in Germany. In some German words, F and V sounds much alike, so VIC was read as "fick" (Google translate explains it) by most Germans. After futile tries with VXN (this time read as "ficken" - an infinitive form of "fick"), someone sane enough decided to rename it to VC-20 - as VolksComputer 20.

Manufacturer Commodore Business Machines

Origin U.S.A
Year of unit 1985
Year of introduction 1981
End of production 1985
CPU MOS 6502
Speed 1,0227MHz
ROM 16kB (Basic)
Colors: 16
Sound: 3 voices
OS: Commodore BASIC
Display modes: Text: 23x22
Graphics: 184x176.


Media: Tape recorder
External 5.25" floppy disk drive
Cartridge slot

Power supply:

7-pin DIN Female:

1,2,3 - Ground
4,5 - +5V DC (or pin 4 n.c.) 2A
6,7 - 9V AC 1A

Commodore 64 power supply is compatible.

Alternatively may be used:
1,2,3 - Ground
4,5 - +5V DC
6 - +12V DC
7 - not connected (DO NOT REVERSE 6 and 7!)

I/O: Serial
Tape connector
Monitor connector
Cartridge port
User port
Joystick port
Possible upgrades: A few are known
Accessories in collection:
Software accessibility: Very Easy (TOSEC, sites, servers)

My unit is late CR (Cost Reduced) vrsion, which has smaller mainboard and has C64-like power supply connector. Earlier units had full-size mainboard, 9V AC two-wired connector and they containde built-in 5V DC regulator. This regulator overheated much and caused many problems.

My unit is in very good condition, I have no idea where it survived over 25 years.


Contents: Starting Image file formats Recording media Video pinout Links


It just boots to BASIC or to cartridge program, if cartridge is installed. From here you can load programs as follows:

LOAD "programname" - loads program "programname" from cassette
LOAD "" - iterates thru all programs on cassette, Commodore key loads it.

Image file formats (popular ones):

Similar to Commodore 64.




Recording media

As VIC-20 is Commodore 64's older brother, tapes are similar. See the same paragraphi in C64 section to get info about recording software.
In many programs you'll see options to switch to VIC-20 mode. The newest WAV-PRG nas such options, so you can convert PRg to TAP/WAV and further to cassette.





5-pin DIN female socket:

1 - +6V DC 10mA (used to power external RF modulator)
2 - Ground
3 - Audio out
4 - Composite video out
5 - Composite video out, in some early units it's luminance.




Links: - Make 32K expansion for your VIC. - VIC-20 community - wiki, forums, information. - Some articles and software - VIC-20 section of well known server.
and - cartridge dumps archive. A few games for download (NOT WORKING). - huh, some games are too strange to describe... - One of the last stands of VIC-20 software libraries outside of TOSEC.