Computer Museum - Commodore VIC 20  
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VIC-20 WGB26443
Commodore VIC 20 serial number WGB 26443 made in West Germany (9 volt input).
Announced in 1980, the VIC 20 was the most popular micro computer of its day. It had good colour and sound and could be connected to a standard television. The VIC video chip from which the computer takes its name was intended for the video game market, which promptly collapsed. Commodore produced many games on cartridges while most software was on audio cassettes. The VIC used the 1530 datasette, Commodore's own tape drive. It could also be connected to Commodore printers and disk drives. The initial low memory could be enhanced by adding more in the cartridge slot. Because of its comparatively low cost, the VIC 20 was a run-away success and the first home computer to sell over one million.
VIC-20 rear view
On the rear of the VIC (from left to right in the photo) there is the cartridge slot, the serial connector for disk drives and printers, the video-out socket, the datassette connector and an RS-232 connector for other peripherals.
Older style TV modulator
More usual TV modulator
The VIC could be connected to a television via a modulator. Two versions existed as shown above. A better picture could be achieved by using a SCART lead instead.
VIC-20 Start-up Screen (unexpanded)
Side view - 9 volt version
The side view shows (from left to right) the control port for joystick or paddles, the on/off switch and the power connector.
The top image shows the early, two-pin 9 volt power conector. The lower one shows the later multi-voltage DIN connector. This, in different shapes, would be standard practice in future Commodore micros, except the C16.
Side view - 5v / 9v version
WGB 26443 WGB 70795 WGB 148572
Serial WGB 26443 (W.Germany) (9v) Serial WGB 70795 (W.Germany) (9v) Serial WGB 148572 (W.Germany)
WGB 206107 UKB 192272  
Serial WGB 206107 (W.Germany) Serial UKB 192272 (England) (VC20)  
Jack Tramiel wanted to dominate the home computer market by producing a cheap, easy to use computer to beat the opposition. The result was the VIC 20, a colour computer that could be connected to a television set.
My first VIC had a 9 volt power supply. Later versions had a multi voltage supply. The VIC was the world's first colour home computer. It could be taken out of the box, connected to a television and it was ready to use. Games could be loaded from cassette or by plugging in a cartridge.
The VIC had a similar keyboard to the PET including the graphic characters but without the separate number keys and a screen of only 22 columns. The four function keys on the right (giving eight options using the shift key) can be programmed.
In Germany the VIC was sold as the Volks Computer or VC20. Curiously, all my VICs were made in (West) Germany except the VC20 which was made in England. I found the 22 column screen limited what I could do and bought a Commodore 64.
VIC-20 User Guide
The VIC 20 had only 3.5kb memory available to the user. This could be increased by adding memory cartridges. These came in 3kb, 8kb and 16kb versions. There were also switchable cartridges that avoided the need to remove them when only the lowest memory was needed. A problem arose because adding memory forced the computer to move its own memory so that a program written without expansion might not run with additional memory installed. Memory could be reconfigured within software. An alternative was to use a motherboard, a piece of hardware which could hold several cartridges. By moving the switches on the motherboard, different memory configurations could be selected.
No expansion - 3583 bytes free  
3k expansion - 6655 bytes free  
8k expansion - 11775 bytes free  
16k expansion - 19967 bytes free  
A large amount of software was also available on cartridge. This automatically configured the necessary memory.
Stack four slot switchable motherboard for VIC 20.
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