---
title: Acorn Computer BBC Master
categories:
- Computers
types:
- Home Computer
origins:
- United Kingdom
years:
- '1986'
cpus:
- 65C102
params:
  name: BBC Master
  image: /media/museum/photos/acorn_bbcmaster_system_1.jpg
  company: /companies/acorn-computer
  company_name: Acorn Computer
  specs:
  - label: NAME
    value: BBC Master
  - label: MANUFACTURER
    value: Acorn Computer
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: United Kingdom
  - label: YEAR
    value: February 1986
  - label: END OF PRODUCTION
    value: '1993'
  - label: BUILT IN LANGUAGE
    value: BBC BASIC IV interpreter
  - label: KEYBOARD
    value: Full stroke 93 key with numeric keypad and 10 function keys
  - label: CPU
    value: 65C102 (an evolution of the 6502)
  - label: SPEED
    value: 2 MHz.
  - label: RAM
    value: 128 KB
  - label: ROM
    value: 128 KB (Expandable)
  - label: TEXT MODES
    value: 40/80 x 25 lines, 20/40/80 x 32, Teletex mode (40 x 25 x 8 colours)
  - label: GRAPHIC MODES
    value: 160/320/640 x 256 dots in 2 to 8 colours
  - label: COLORS
    value: 8 among 16
  - label: SOUND
    value: 4 chanels, 8 octaves - SN76489 sound generator
  - label: SIZE / WEIGHT
    value: 46.7 (W) x 34.5 (D) x 7.5 (H) cm.
  - label: I/O PORTS
    value: Tube expansion, BBC High Speed Bus, FDD interface, User interface, RS423 serial, Analog, Econet network, Parallel, tape recorder, TV/RF, RGB & Composite outputs,
  - label: BUILT IN MEDIA
    value: Cassette & FDD interfaces
  - label: OS
    value: MOS
  - label: POWER SUPPLY
    value: Built-in switching power supply unit
  - label: PERIPHERALS
    value: External FDD unit, processor card, etc.
  - label: PRICE
    value: £499
  tabs:
  - photos
  - hardware
  - emulators
  - links
  - docs
  forum_thread: 831
  photos:
  - title: BBC MASTER
    subtitle: ''
    text: ''
    image: /media/museum/photos/acorn_bbcmaster_system_2.jpg
  - title: 'KEYBOARD CLOSE-UP #1'
    subtitle: ''
    text: Notice the function-key help insert which can be changed according to the software used.
    image: /media/museum/photos/acorn_bbcmaster_keyboardcloseup_2.jpg
  - title: 'KEYBOARD CLOSE-UP #2'
    subtitle: ''
    text: Twin cartridge housings, numeric keypad and Master series logo.
    image: /media/museum/photos/acorn_bbcmaster_keyboardcloseup_1.jpg
  - title: REAR CONNECTORS
    subtitle: ''
    text: |-
      **(1)** Econet network DIN plug\
      **(2)** Audio out RCA jack\
      **(3)** Tape recorder DIN plug\
      **(4)** Serial RS423 DIN plug\
      **(5)** Analogue port DB15 connector\
      **(6)** Analogue RGB video out\
      **(7)** Composite video out\
      **(8)** TV/RF video out\
      **(9)** Optional modem cable
    image: /media/museum/photos/acorn_bbcmaster_back_1.jpg
  - title: BOTTOM CONNECTORS
    subtitle: ''
    text: |-
      **(1)** Auxiliary power supply - +5V & +12V\
      **(2)** External disk drive unit. FD controller chip is provided on the mainboard\
      **(3)** Parallel printer\
      **(4)** User port\
      **(5)** 1 MHz bus\
      **(6)** Tube interface
    image: /media/museum/photos/acorn_bbcmaster_bottom_1.jpg
  - title: INSIDE
    subtitle: ''
    text: |-
      **(1)** Switching power supply unit\
      **(2)** Optional modem card\
      **(3)** Optional ROM card. Allows 13 ROM chips to be added\
      **(4)** ROM cartridge connectors\
      **(5)** Setup and clock battery backup
    image: /media/museum/photos/acorn_bbcmaster_inside_1.jpg
  - title: MAINBOARD
    subtitle: ''
    text: |-
      **(1)** Bottom connectors\
      **(2)** Cartridge connectors\
      **(3)** Rom socket area
    image: /media/museum/photos/acorn_bbcmaster_mainboard_1.jpg
  - title: SET OF MANUALS
    subtitle: ''
    text: The "Welcome Guide" is very detailed, giving all the information about internal hardware and built-in software.
    image: /media/museum/photos/acorn_bbcmaster_manuals_1.jpg
  hardware:
  - title: OPUS FD UNIT
    subtitle: ''
    text: |-
      This dual 5.25" floppy drive unit could be used with Acorn DFS or Opus DDOS operating systems.\
      Users could select single or double-sided, 40 or 80 track format.\
      Depending on the format used, a diskette could store from 100 KB to 360 KB of information.\
      Power is supplied by the BBC auxiliary connector.
    image: /media/museum/hardware/acorn_bbcmaster_opusfdunit_1.jpg
  - title: 'DUAL ROM SUPPORT #1'
    subtitle: ''
    text: Two ROM modules can be inserted in this support. Here one of them is equipped with a null insertion socket.
    image: /media/museum/hardware/acorn_bbcmaster_rommodule_1.jpg
  - title: 'DUAL ROM SUPPORT #2'
    subtitle: ''
    text: ''
    image: /media/museum/hardware/acorn_bbcmaster_rommodule_2.jpg
  - title: 64 KB RAM CARD
    subtitle: ''
    text: ''
    image: /media/museum/hardware/acorn_bbcmaster_rammodule_1.jpg
  - title: FUNCTION KEY INSERTS
    subtitle: ''
    text: Users could insert function key reminders for some of the major software above the row of function keys.
    image: /media/museum/hardware/acorn_bbcmaster_inserts_1.jpg
  - title: VOLTMACE DELTA CONTROLLERS
    subtitle: ''
    text: 'Voltmace modified its Database videogame system controllers to be sold for micro-computers, mainly Acorn systems : BBC and Electron (with Plus-1 interface). As the keypad was of no use anymore, it was reduced to only 3 fire buttons.'
    image: /media/museum/hardware/voltmace_joysticks.jpg
  emulators:
  - title: The BBC Lives !
    url: http://www.nvg.org/bbc/emulators.php3
    platform: MS DOS
    text: This excellent site has a complete list of Acorn systems emulators
  links:
  - title: Acornusers.org
    url: http://www.acornusers.org/
    text: The acornusers.org server hosts several Acorn web sites
  - title: comp.sys.acorn.games FAQ
    url: http://www.landfield.com/faqs/acorn/games/
    text: newsgroup FAQ
  - title: RetroBBC
    url: http://www.strafom.force9.co.uk/bbc/Retrobbc/Index.htm
    text: Mainly a software archive. Cool !
  - title: The BBC and Master Computer Public Domain Library
    url: http://8bs.com/
    text: Lots of stuff to see and download
  - title: The BBC Lives!
    url: http://bbc.nvg.org/
    text: The net's largest site catering for enthusiasts of Acorn's range of 8-bit micros
  - title: The Stairway to Hell
    url: http://www.stairwaytohell.com/
    text: Electron and BBC support. Excellent site with a lot of stuff !
  - title: The Unofficial Acorn Computer User WWW Server
    url: http://www.poppyfields.net/acorn/
    text: ''
  - title: Web Wiz CAPTCHA
    url: http://www.webwizcaptcha.com
    text: Programming of Acorn computers
  docs:
  - title: ADVANCED REFERENCE MANUAL FOR THE BBC MASTER
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/acorn_bbc-master_advanced_reference_manual.jpg
    text: |-
      [**ADVANCED REFERENCE MANUAL FOR THE BBC MASTER**](http://members.aon.at/~musher/bbc/essentials.htm)written by Ian Bishop Laggett

       compiled/archived by Chris Richardson\
       type of document : RTF\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  - title: BBC MASTER SERIES MICROCOMPUTER SERVICE MANUAL
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/vide.gif
    text: |-
      [**BBC MASTER SERIES MICROCOMPUTER SERVICE MANUAL**](http://members.aon.at/~musher/bbc/essentials.htm)written by Acorn Computers Limited

       compiled/archived by Chris Richardson\
       type of document : RTF\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  - title: BBC MASTER REFENCE MANUAL - PART 1
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/acorn_bbc-master_reference-manual_part1.jpg
    text: |-
      [**BBC MASTER REFENCE MANUAL - PART 1**](http://members.aon.at/~musher/bbc/essentials.htm)written by Acorn Computers Limited

       compiled/archived by Chris Richardson\
       type of document : PDF\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  - title: BBC MASTER REFENCE MANUAL - PART 2
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/acorn_bbc-master_reference-manual_part2.jpg
    text: |-
      [**BBC MASTER REFENCE MANUAL - PART 2**](http://members.aon.at/~musher/bbc/essentials.htm)written by Acorn Computers Limited

       compiled/archived by Chris Richardson / Keith Howell\
       type of document : PDF\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  - title: BBC MASTER 512 USER GUIDE
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/acorn_bbc-master-512_user-guide.jpg
    text: |-
      [**BBC MASTER 512 USER GUIDE**](http://members.aon.at/~musher/bbc/essentials.htm)written by Acorn Computers Limited

       compiled/archived by Chris Richardson / Daniel G. van der Pol\
       type of document : ZIP\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  - title: MASTER OPERATING SYSTEM
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/acorn_bbc-master-operating-system.jpg
    text: |-
      [**MASTER OPERATING SYSTEM**](http://members.aon.at/~musher/bbc/essentials.htm)written by David Atherton

       compiled/archived by Chris Richardson\
       type of document : PDF\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  - title: MASTER COMPACT APPLICATION NOTE
    url: http://members.aon.at/~musher/bbc/essentials.htm
    cover: /media/museum/docs/couvs/vide.gif
    text: |-
      [**MASTER COMPACT APPLICATION NOTE**](http://members.aon.at/~musher/bbc/essentials.htm)written by Acorn Computers Limited

       compiled/archived by Chris Richardson\
       type of document : ZIP\
       source : [BBC Documentation Project](http://www.bbcdocs.com)
  related:
  - /museum/acorn-computer-atom
  - /museum/acorn-computer-bbc-master-aiv
  - /museum/acorn-computer-bbc-master-compact
  - /museum/acorn-computer-bbc-model-a-b-b
  - /museum/acorn-computer-electron
  oc_id: 850
  source:
    url: https://web.archive.org/web/20230608145639/http://www.old-computers.com/museum/computer.asp?c=850
    date: '2023-06-08'
---

The BBC Master was an enhanced version of the [BBC Model B](/museum/acorn-computer-bbc-model-a-b-b/) providing improved features, but sadly also introducing compatibility problems with earlier BBC systems.

These features were: loads more memory such as shadow, sideways and private RAM, 4 sound channels, twin cartridge sockets, as well as several built-in ROM software packages like **View** (word processor), **ViewSheet** (spreadsheet), **ADFS** (Advanced Filing System), a text editor and terminal utilities.

Like the Model B, the system had so many I/O ports that most of them had to be placed under the case. Luckily, they only used flat-cable connectors.

When it was released, the BBC Master met with great success. From 1986 to 1989, about 200,000 systems were sold, mainly to U.K. schools and universities.\
Several enhanced versions of the Master were launched in the following months:\
\- The **Master 512** was a Master 128 with 512 KB of RAM and an internal 80186 processor. It could be upgraded up to 1024 KB and ran MS-DOS.\
\- The **Master Turbo** was a Master 128 with a 65C02 as a second processor.

The BBC Master and [Master Compact](/museum/acorn-computer-bbc-master-compact/) could be considered the most accomplished 8-bit 'home' computers and among the last mass-produced 8-bit machines. Production ended in 1993.\
While developing and marketing the BBC Master, Acorn realized the PC world was moving on from 8-bit to 16-bit processors and started developing their own 32-bit chip, the Acorn RISC Machine, or ARM.