website/content/museum/commodore-vic-20.md

---
title: Commodore VIC 20
categories:
- Computers
types:
- Home Computer
origins:
- U.S.A.
years:
- '1981'
cpus:
- Commodore Semiconductor Group 6502A
params:
  name: VIC 20
  image: /media/museum/photos/commodore_vic20_1.jpg
  logo: /media/museum/logos/commodore_vic20_logo.gif
  company: /companies/commodore
  company_name: Commodore
  specs:
  - label: NAME
    value: VIC 20
  - label: MANUFACTURER
    value: Commodore
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: U.S.A.
  - label: YEAR
    value: May 1981
  - label: END OF PRODUCTION
    value: January 1985
  - label: BUILT IN LANGUAGE
    value: CBM Basic V2
  - label: KEYBOARD
    value: Full-stroke keyboard, 4 function keys, 66 keys
  - label: CPU
    value: Commodore Semiconductor Group 6502A
  - label: SPEED
    value: 1.0227 Mhz
  - label: CO-PROCESSOR
    value: VIC-I (6560) for sound and graphics.
  - label: RAM
    value: 5 KB (3583 bytes free), expandable up to 32 KB
  - label: VRAM
    value: Screen memory shared with regular RAM
  - label: ROM
    value: 16 KB
  - label: TEXT MODES
    value: 23 rows x 22 columns
  - label: GRAPHIC MODES
    value: 184 x 176
  - label: COLORS
    value: 8 character colors, 16 background/border colors
  - label: SOUND
    value: 3 voices / 3 octaves
  - label: SIZE / WEIGHT
    value: 40.3 x 20.4 x 7.2 cm / 1,8 Kg
  - label: I/O PORTS
    value: 1 joystick port, 1 user port, 1 serial port, 1 cartrige port, Composite video output, tape interface
  - label: POWER SUPPLY
    value: External power supply unit, 18 Watts
  - label: PRICE
    value: $299.95 (1981, U.S.A.)
  tabs:
  - photos
  - adverts
  - hardware
  - software
  - emulators
  - links
  - docs
  - videos
  forum_thread: 262
  photos:
  - title: EVOLUTION OF THE VIC 20 CASE.
    subtitle: ''
    text: ''
    image: /media/museum/photos/2vic20.jpg
  - title: INSIDE VIC-20
    subtitle: ''
    text: |-
      The VIC-20 offered one of the first compact architectures which would later inspire the designs of many home computer manufacturers.

      **(1)** The keyboard can access up to 4 character sets and 8 programmable functions.\
      **(2)** Housing for ROM or RAM expansion cartridges.\
      **(3)** Power connector. Power is supplied by an external supply unit.\
      **(4)** On/Off switch.\
      **(5)** Analog port connector for a joystick, light pen or measuring instrument.\
      **(6)** ROM chips holding the Basic language, character generator, and Input/Output routines.\
      **(7)** 8-bit 6502 microprocessor from MOS Technology.\
      **(8)** Aerial TV and RGB video output.\
      **(9)** Serial interface connector. Able to manage several peripherals simultaneously.\
      **(10)** Specialized chip dealing with video and sound generation.\
      **(11)** Chips holding 5KB of RAM.\
      **(12)** Keyboard connector.\
      **(13-14)** Two specialized chips for input/output management.\
      **(15)** Serial mode user connector.\
      **(16)** Commodore tape recorder connector.
    image: /media/museum/photos/commodore_vic20_inside_1.jpg
  - title: VIC-20 BOX
    subtitle: ''
    text: ''
    image: /media/museum/photos/commodore_vic20_box_1.jpg
  - title: 'BOX #2'
    subtitle: ''
    text: ''
    image: /media/museum/photos/commodore_vic20_box_2.jpg
  - title: VIC-1001
    subtitle: ''
    text: |-
      Before being introduced into the North American market, the VIC-20 was sold in Japan under the model name VIC-1001.\
      It featured Japanese 'Katakana' characters in addition to the occidental ASCII characters set.

      Thanks to Michael Huebmer for this picture
    image: /media/museum/photos/commodore_vic1001_2.jpg
  - title: VIC-1001 KEYBOARD
    subtitle: ''
    text: |-
      Notice the japanese characters

      Thanks to Michael Huebmer for this picture
    image: /media/museum/photos/commodore_vic1001_keyboard.jpg
  - title: VIC-1001 BOX
    subtitle: ''
    text: ''
    image: /media/museum/photos/commodore_vic1001_box_1.jpg
  adverts:
  - title: 'ADVERT #1'
    subtitle: ''
    text: Picture courtesy of [Steve Browning, www.sbrowning.com/vintage](http://www.sbrowning.com/vintage).
    image: /media/museum/pubs/commodore_vic20_pub_1.jpg
  - title: 'ADVERT #2'
    subtitle: ''
    text: |-
      Yes, it's really him – William Shatner (Captain Kirk).\
      Did they really use VIC-20 in the Enterprise?\
      That would certainly explain a lot of things...

      Picture courtesy of [Steve Browning, www.sbrowning.com/vintage](http://www.sbrowning.com/vintage).
    image: /media/museum/pubs/commodore_vic20_pub_2.jpg
  - title: 'ADVERT #3'
    subtitle: ''
    text: Picture courtesy of Steve Browning, www.sbrowning.com/vintage.
    image: /media/museum/pubs/commodore_vic20_pub_3.jpg
  - title: 'ADVERT #4 (1982)'
    subtitle: ''
    text: Circa September, 1982. This is likely one of the final Commodore advertisements for the VIC-20, as the C64 was soon to be launched.
    image: /media/museum/pubs/commodore_vic20_pub_4.jpg
  - title: 'ADVERT #5'
    subtitle: ''
    text: ''
    image: /media/museum/pubs/commodore_vic20_pub_price-of-a-toy.jpg
  - title: NEW ZEALAND ADVERT
    subtitle: ''
    text: dated February 1984 from Bits & Bytes
    image: null
  - title: WONDER COMPUTE
    subtitle: ''
    text: ''
    image: /media/museum/pubs/commodore_vic20_adv_wonder-compute.jpg
  - title: VC20 GERMAN ADVERT
    subtitle: ''
    text: Thanks to Christian Hart for this scan
    image: /media/museum/pubs/commodore_vc20_pub-de_1.jpg
  - title: ITALIAN AD
    subtitle: ''
    text: |-
      “Why be content with a video game system?\
      Today, the VIC-20 is available at a special price.”

      Courtesy of **http://angelmemories.cjb.net/**
    image: /media/museum/pubs/commodore_vic20_aditaly_1.jpg
  - title: SPANISH ADVERT (MAY 1982)
    subtitle: ''
    text: ''
    image: null
  - title: PROMOTIONAL PICTURE
    subtitle: ''
    text: ''
    image: /media/museum/pubs/commodore-vic20_prm_1.jpg
  - title: COMMODORE WATCHES!
    subtitle: ''
    text: |-
      While manufacturing and selling calculators in 1977, Commodore sold wristwatches.

      Thanks to **Chuck Guzis**
    image: /media/museum/pubs/commodore_64_watchad_1.jpg
  hardware:
  - title: VIC-1525
    subtitle: Dot-matrix printer.
    text: ''
    image: /media/museum/hardware/commodore_vic-1525_printer_1.jpg
  - title: TAPE-RECORDER
    subtitle: Data storage unit.
    text: ''
    image: /media/museum/hardware/commodore_vic20_taperecorder_1.jpg
  - title: SERIAL RS232 MODULE
    subtitle: Serial connectivity module.
    text: ''
    image: /media/museum/hardware/commodore_vic20_serialmodule_1.jpg
  - title: VICMODEM
    subtitle: Model 1600
    text: The official VIC-20 modem.
    image: /media/museum/hardware/commodore_vic20_vicmodem_1.jpg
  - title: 8 KB RAM MODULE
    subtitle: 8K RAM expansion cartridge.
    text: ''
    image: /media/museum/hardware/commodore_vic20_8krammodule_1.jpg
  emulators:
  - title: Pfau Zeh
    url: http://www.classicgaming.com/pfauzeh/
    platform: Windows
    text: Nice VIC-20 emulator for Windows
  - title: Power20
    url: http://www.infinite-loop.at/Power20/index.html
    platform: Apple
    text: VIC-20 emulator for MacOS
  - title: MESS
    url: http://www.mess.org/
    platform: Multiplatform
    text: MESS emulates the VIC-20
  - title: VICE
    url: http://www.viceteam.org/
    platform: Multiplatform
    text: VICE is a multiplatform emulator that supports the Commodore VIC-20, C64, C128, and PET models.
  links:
  - title: Arma's Home page
    url: http://www.timsplace.plus.com/
    text: VIC 20 dedicated site, with a lot of tape inlay scans!
  - title: Commodore VIC-20 file archive
    url: http://www.funet.fi/pub/cbm/vic20/index.html
    text: The title says it all...
  - title: Commodore VIC-20 Tribute page
    url: http://www.geocities.com/rmelick/new_page_2.htm
    text: 'Lot of stuff here : history, technical documents, interviews, etc.'
  - title: Denial - The Commodore VIC-20 Community
    url: http://sleepingelephant.com/denial/
    text: Forum, Wiki, Roms, Docs, FAQs, News, Links
  - title: GameBase VIC20
    url: http://home.wanadoo.nl/dirkhuppelde/
    text: VIC20 game database
  - title: Ray Carlsens's Commodore repair articles
    url: http://personalpages.tds.net/~rcarlsen/cbm.html
    text: 'Commodore Repair Articles (Ray Carlsen): Includes detailed repair tips such as “Repairing the VIC-20: Chips vs. Symptoms and Diagnostics''''.'
  - title: The Geek site
    url: http://www.kdef.com/geek/vic/
    text: VIC-20 software, emulators, specifications, and more.
  - title: VIC-20 Cartridge Software Reviews
    url: http://www.zimmers.net/anonftp/pub/cbm/vic20/Cartzilla.html#sea-wolf
    text: Many game reviews by Ward F. Shrake
  - title: Week End Gamer - VIC 20 Archive
    url: http://www.weekend-gamer.co.uk/Vic20/Index.htm
    text: Great! Lot of interesting stuff here
  - title: Wikipedia - VIC-20 article
    url: http://en.wikipedia.org/wiki/Commodore_VIC-20
    text: ''
  docs:
  - title: PROGRAMMER'S REFERENCE GUIDE
    url: null
    cover: /media/museum/docs/couvs/commodore_vic20_programmers-reference-guide.jpg
    text: |-
      **PROGRAMMER'S REFERENCE GUIDE**\
      written by Commodore

       compiled/archived by Asbjorn Djupdal\
       type of document : PDF\
       source : www.old-computers.com
  videos:
  - title: Commodore Vic 20 commercial - meeting
    url: https://www.youtube.com/watch?v=IUKUHjBhb2Q
    text: 'Length: 31 s'
  - title: Commodore Vic 20 commercial - prepared for ?
    url: https://www.youtube.com/watch?v=3nkgZZn6Rzk
    text: 'Length: 31 s'
  - title: Commodore Vic 20 commercial - 2 kind of teenagers
    url: https://www.youtube.com/watch?v=UMLsQAJ-oHU
    text: 'Length: 31 s'
  - title: Commodore Vic 20 commercial - looking for a job
    url: https://www.youtube.com/watch?v=Lql-otlQfNo
    text: 'Length: 32 s'
  - title: Commodore Vic 20 commercial - fish tank
    url: https://www.youtube.com/watch?v=0pYMHm_Y60s
    text: 'Length: 31 s'
  - title: Commodore Vic 20 commercial - fish tank
    url: https://www.youtube.com/watch?v=P0_mF4J23R0
    text: 'Length: 12 s'
  - title: Commodore Vic 20 commercial - Neighborhood
    url: https://www.youtube.com/watch?v=EG6NR7_Jfk0
    text: 'Length: 11 s'
  - title: Commodore Vic 20 commercial - thank you
    url: https://www.youtube.com/watch?v=qkBvhHYV5qE
    text: 'Length: 11 s'
  - title: Commodore Vic 20 commercial - William Shatner
    url: https://www.youtube.com/watch?v=PUEI7mm8M7Q
    text: 'Length: 28 s'
  software:
  - /software/adventure
  - /software/alien-a-k-a-super-alien
  - /software/capture-the-flag
  - /software/jupiter-lander
  - /software/mastermind
  - /software/pirate-s-cove-adventure
  - /software/seawolf
  - /software/terraguard
  - /software/the-count
  - /software/vic-avenger
  - /software/voodoo-castle
  oc_id: 252
  source:
    url: https://web.archive.org/web/20230528042202/http://www.old-computers.com/museum/computer.asp?c=252
    date: '2023-05-28'
---

The VIC-20 – a "family" version of the [PET series](/museum/commodore-pet-2001/) (using the same microprocessor and Basic language) – was the first computer to sell more than one million units. Once dubbed the **MicroPET** during the 1980 Computer Electronics Show, it later became known as the VIC-20. VIC referenced the **VIC-I** (Video Interface Chip) chip used for graphics and sound. There does not seem to be any obvious rationale behind the usage of the number 20, other than the fact that it was close to the 22 characters per line and to the combined RAM and ROM memory in the machine (5 KB RAM + 16 KB ROM), or the total 8 KB Basic, 8 KB Kernel and 4 KB Character maps...

Regarding the name, **Michael Tomczyk**, (manager of the VIC project) recalls:\
"*VIC sounded like a truck driver, so I insisted on attaching a number. I picked ‘20’ and when Jack Tramiel asked, ‘Why 20?’ I replied, ‘because it's a friendly number and this has to be a friendly computer.*' He agreed. The number 20 has no relation to any technical feature -- just my idea of a friendly sounding number. That sounds a bit bizarre looking back on it, but we did a lot of things by instinct in those days."

The VIC-20 was designed by **Bob Yannes** who also created the SID chip for the C64. He later joined Ensoniq to design synthesizers.

The Video Interface Chip (or ‘VIC’ as it is commonly called), is one of the most important silicon chips in the VIC-20 microcomputer, coming second only to the 6502A microprocessor itself. The VIC is a specially constructed input-output (I/O) chip that offers a large variety of functions, but as suggested by its name, is primarily concerned with the production of the video output signal. It was originally intended to be sold to third-party manufacturers for use in video game machines. Demand for the chip was low, and so Commodore decided to make their own system to recoup their losses.

The VIC-20 was initially launched in Japan in late 1980 (under the ‘[VIC-1001](/museum/commodore-vic-1001/)’ name) with a Japanese 'Katakana' set of characters. It was subsequently released in North America in May of 1981. Though these are the "official" release dates, several prototypes of the Commodore VIC-20 were reportedly available in late 1979. These early machines offered only 4 KB of RAM and used a different set of game cartridges.

Thanks to the colorful graphics and low cost, the VIC-20 was an immediate success. At its peak, more than 9000 units rolled off the assembly line each day. Adding to its success was the fact that it was the first color computer to break the $300 (USD) price barrier.

A wide range of peripherals and software were developed for the VIC-20. The failed [Commodore 16](/museum/commodore-c16/) eventually became the successor of the VIC-20.

---

Contributors: Brian Bagnall, Rick Melick