BBC Micro

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BBC Micro, (BBC Microcomputer System) a series of 8-bit 6502 based home computers by Acorn Computers Ltd, initially designed by a team including Steve Furber and Sophie Wilson, first released in December 1981. The Micro was contracted by the British Broadcasting Corporation (BBC) after a call for bids for a computer to accompany the TV series and literature for their Computer Literacy Project , which was won by Acorn with the Proton, a successor of the Acorn Atom - renamed the BBC Micro. Acorn also employed the machine to simulate and develop the ARM architecture which, many years later, has become hugely successful.

=Hardware= The BBC Micro had a 6502 processor running at full 2 MHz speed, accessing fast DRAM, alternating concurrently with the MC6845 video display controller, featuring eight display modes for text and graphics varied between 20 and 40-column text suitable for a TV, to 80-column text requiring an RGB-connected video monitor. As noted by Steve Furber in a recent interview, the alternating fast 4 MHz RAM access required some address multiplexing using exactly the 81LS95 tri-state octal buffer from National Semiconductor - for unknown reasons, 81LS95 from other vendors were not working. Multiple input/output ports were available to connect with peripherals or other machines, such as serial PS-423 ports, parallel ports, analogue input ports with ADC for instance used by a joystick, light pen input, an expansion connector (the "1 MHz bus") to expand the system with additional hardware such as the BBC Micro expansion, and the Tube interface to connect a secondary processor. The BBC Micro had an integrated keyboard and a cassette interface. Floppy disks were optional through the Intel 8271 programmable floppy disk controller, in later models replaced by Western Digital's FD1771. The Texas Instruments SN76489 was responsible for sound. Phoneme based speech synthesis using TI's TMS5220 speech chip with a custom Acorn ROM of Kenneth Kendall's voice was optional. =Models= The initial BBC Micro was shipped as Model A with 16 KiB of user RAM, and Model B with 32 KiB. The Acorn Electron was a budget version of the B-Model released by Acorn in 1983. Two export models were developed for the US and West Germany in 1983. As a sideline, the Acorn Business Computer (ABC) range of machines was announced in October 1984. The Model B+ in mid 1985, increased the total RAM to 64 KiB, the B+128 came with an additional 64 KiB (4 × 16 KBi "Sideways" RAM banks) to give a total RAM of 128 KiB. The BBC Master with integrated floppies followed in 1986 with an enhanced 65SC12 CPU, and expandable 128 KiB RAM as default, and remained in production until 1993. =Software= The Acorn Machine Operating System (MOS) was held in 16 KiB of ROM on the motherboard. A further 16 KiB ROM contained the BBC BASIC interpreter. Acornsoft was the major publisher of software for the BBC Micro and Acorn Electron, who released Acornsoft Chess written by Arthur Norman and Nick Pelling. Other British companies in the fast growing software market were Micro Power, Computer Concepts, Ltd. and Bug-Byte.

=Chess Programs= =First Computer Go Tournament= The BBC Micro Go Tournament was held in London, on January 7 and 8, 1984, sponsored by Acornsoft. All eight programs ran on BBC Micro. The Go playing program by Bronyslaw Przybla won the event.
 * Category:BBC Micro

=See also=
 * Acorn Atom
 * Acorn Archimedes
 * BBC Micro Bit

=Publications=
 * John Vaux (1983). Micro takes on Chess Machine. Acorn User, No. 8, pdf
 * Tony Harrington (1983). University Challenge - Martin Bryant and White Knight. Personal Computer World, August 1983, pdf hosted by Mike Watters
 * Alex Bell (1983). Chess for three gives the White Knight a winning gambit. The Micro User Magazine, December 1983
 * Arthur Norman, Gillian Cattell (1983). LISP on the BBC Microcomputer. Acornsoft » LISP

=Manuals=
 * John Coll, David Allen (ed.) (1984). BBC Microcomputer System User Guide. pdf
 * Acorn Computer (1985). BBC Microcomputer Service Manual. Section 1, Models A + B, pdf
 * Circuit Diagram (pdf)

=Forum Posts=
 * Okay, i know now: Colossus and BBC ACORN A: White Knight by Frank Phillips, CCC, May 06, 2002
 * those good old times... in the 70-80ties by Thorsten Czub, CCC, May 06, 2002

=External Links=

BBC Micro

 * BBC Micro from Wikipedia
 * BBC Micro expansion unit from Wikipedia
 * Tube (BBC Micro) from Wikipedia
 * BBC Microcomputer Model B by Terry Stewart (Tezza)
 * Acorn BBC Micro Model B - Computing History
 * DigiBarn Systems: BBC Microcomputer by Acorn
 * Chris Turner - Acorn and the BBC Micro - Computing History
 * Wouter's BBC micro software, scans, pictures, etc.
 * Acorn Electron from Wikipedia
 * BBC Master from Wikipedia
 * ARX, Arthur and RISC OS by Paul Fellows, RISC OS User Group Of London, October 15, 2012 » Acorn Archimedes

Software

 * Acorn MOS from Wikipedia
 * BBC BASIC from Wikipedia » BBC BASIC
 * BBC Micro Software at the Centre for Computing History
 * Complete BBC Games Archive
 * BBC Games Archive - The Stairway To Hell
 * Acornsoft - BBC Micro/Acorn Electron Professional Games - Acorn Electron World
 * BBC Games from the past - MicroPower Games
 * BBC Computer Related Manuals: Games

Chess Programs

 * Beeb Chess - Complete BBC Games Archive » Beeb Chess
 * Chess - Complete BBC Games Archive » Chess (David Thompson)
 * Chess (Micro Power) - Complete BBC Games Archive » Micro Power Chess
 * Chess (V2.1) - Complete BBC Games Archive » Acornsoft Chess
 * Colossus Chess 4 for BBC Micro (1986) Ad Blurbs - MobyGames » Colossus Chess

Computer Literacy Project

 * The Computer Programme from Wikipedia
 * BBC - Computer Literacy Project - Computing History
 * Making the Most of the Micro from Wikipedia
 * Micro Live from Wikipedia
 * David Allen and Steve Lowry - The BBC Micro and Computer Literacy Project - Computing History

Misc

 * Computer Go - Past Events - Acorn 1984 » Go
 * Building the BBC Micro (The Beeb) with Steve Furber - Computerphile, YouTube Video


 * The BBC Model B Microcomputer System: As seen in Tezza's classic computer collection, YouTube Video

=References= Up one Level