View source for BBC Micro

{{short description|Series of British microcomputers by Acorn}}
{{Use British English|date=April 2022}}
{{Use dmy dates|date=June 2025}}
{{Infobox computing device
| name = BBC Micro
| logo = BBC owl.svg
| logo_size = 48
| image = BBC Micro Front Restored.jpg
| image_size = 250
| caption = BBC Micro Model A/B (standard configuration)
| developer = [[BBC]]
| manufacturer = [[Acorn Computers]]
| family =
| type = [[8-bit computing|8-bit]] [[home computer]]
| generation =
| lifespan = 1981–1994
| discontinued = {{end date and age|1994|df=y}}
| media = <templatestyles src="Fraction/styles.css"/><!--fixes fraction display in links-->[[Cassette tape]], floppy disk (optional) – [[5.25-inch floppy disk|{{Fraction|5|1|4}}-inch]] or (later) [[3.5-inch floppy disk|{{fraction|3|1|2}}-inch]], hard disk also known as 'Winchester' (rare), [[Laserdisc]] ([[BBC Domesday Project]])
| os = [[Acorn MOS]]
| power = 50 W
| cpu = 2&nbsp;MHz [[MOS Technology 6502]]/6512
| memory = {{unbulleted list|16–32 [[Kibibyte|KiB]] (Model A/B)|64–128&nbsp;KiB (Model B+)|128&nbsp;KiB (Master)|Plus 32–128&nbsp;KB [[Read-only memory|ROM]], expandable to 272&nbsp;KiB}}
| storage = {{unbulleted list|100–800 KB (DFS)|160–1280&nbsp;KB (ADFS floppy disks)|20&nbsp;MB (ADFS hard disk)}}
| display = [[PAL]]/[[NTSC]], [[Ultra high frequency|UHF]]/[[Composite video|composite]]/[[Transistor-transistor logic|TTL]] [[RGB]]
| graphics = {{unbulleted list|640×256, 8 colours ([[Motorola 6845]], various [[framebuffer]] modes)|78×75, 8 colours ([[Mullard SAA5050]] [[Teletext]] chip)}}
| sound = {{unbulleted list|[[Texas Instruments SN76489]], 4 channels, mono|[[Texas Instruments LPC Speech Chips|TMS5220]] speech synthesiser with phrase [[Read-only memory|ROM]] (optional)}}
| input = Keyboard, twin analogue joysticks with fire buttons, lightpen
| controllers =
| connectivity = Printer parallel, [[RS-423]] serial, user parallel, [[Econet]] (optional), 1&nbsp;MHz bus, [[Tube (BBC Micro)|Tube]] second processor interface
| dimensions =
| weight =
| compatibility =
| predecessor = [[Acorn Atom]]
| successor = [[Acorn Archimedes]]
| related = [[Acorn Electron]]
| website =
| carrier =
| releasedate = {{start date and age|1981|12|01|df=y}}
| price = £235 Model A, £335 Model B (in 1981)
| unitssold = Over 1.5 million
| unitsshipped =
| output =
| topgame =
}}

The '''BBC Microcomputer System''', or '''BBC Micro''', is a family of [[microcomputer]]s developed and manufactured by [[Acorn Computers]] in the early 1980s as part of the [[BBC]]'s [[Computer Literacy]] Project. Launched in December 1981, it was showcased across several educational BBC television programmes, such as ''[[The Computer Programme]]'' (1982), ''[[Making the Most of the Micro]]'' and ''Computers in Control'' (both 1983), and ''[[Micro Live]]'' (1985). Created in response to the BBC's [[call for bids]] for a microcomputer to complement its broadcasts and printed material, Acorn secured the contract with its rapidly prototyped "Proton" system, which was subsequently renamed the BBC Micro.

Although it was announced towards the end of 1981, production issues initially delayed the fulfilment of many orders, causing deliveries to spill over into 1982. Nicknamed the "Beeb", it soon became a fixture in British schools, advancing the BBC's goal of improving computer literacy. Renowned for its strong build quality and extensive connectivity, including ports for peripherals, support for [[Econet]] networking, and the option of second processors via the [[Tube (BBC Micro)|Tube interface]], the BBC Micro was offered in two main variants: the 16 KB Model A (initially priced at £299) and the more popular 32 KB Model B (priced at £399). Although it was costlier than many other [[home computer]]s of the era, it sold over 1.5 million units, boosted by the BBC's brand recognition and the machine's adaptability.

The BBC Micro's impact on [[education in the United Kingdom]] was notable, with most schools in Britain acquiring at least one unit, exposing a generation of pupils to computing fundamentals. Central to this was its built-in [[BBC BASIC]] programming language, known for its robust feature set and accessible syntax. As a home system, the BBC also fostered a community of enthusiasts who benefited from its flexible architecture, which supported everything from disk interfaces to speech synthesis. Through these expansions and its broader software library, the BBC Micro had a major impact in the development of the UK's home-grown software industry. Acorn's engineers used the BBC Micro as both a development platform and a reference design to simulate their pioneering [[ARM architecture]], now one of the most widely deployed [[Central processing unit|CPU]] designs worldwide. This work influenced the rapid evolution of [[Reduced instruction set computer|RISC-based processing]] in mobile devices, embedded systems, and beyond, making the BBC Micro an important stepping stone in computing.

The BBC Micro had multiple display modes, including a [[Teletext]]-based Mode 7 that used minimal memory, and came with a full-travel keyboard and ten user-configurable function keys. Hardware interfaces were catered for with standard analogue inputs, a serial and parallel port, and a cassette interface that followed the CUTS (Computer Users' Tape Standard) variation of the [[Kansas City standard]]. In total, nine BBC-branded microcomputer models were released, although the term "BBC Micro" generally refers to the first six versions (Model A, B, B+64, B+128, Master 128, and Master Compact). Later BBC models are typically classed as part of [[Acorn Archimedes|Acorn's Archimedes]] line.

== History ==
[[File:BBC Micro people in 2008.jpg|thumb|left|Some of the BBC Micro team in 2008]]
During the early 1980s, the BBC started what became known as the ''BBC Computer Literacy Project''.<ref>John Radcliffe and Roberts Salkeld (1983), [https://clp.bbcrewind.co.uk/media/Towards%20Computer%20Literacy.pdf Towards Computer Literacy – The BBC Computer Literacy Project 1979–1983], BBC Education.<br /> [http://www.naec.org.uk/organisations/bbc-computer-literacy-project/towards-computer-literacy-the-bbc-computer-literacy-project-1979-1983 HTML version], National Archive of Educational Computing. Accessed 2024-01-29</ref><ref>{{Cite web |last=Content |first=BBC Archive |title=BBC Computer Literacy Project |url=https://clp.bbcrewind.co.uk/ |access-date=2025-03-05 |website=clp.bbcrewind.co.uk |language=en}}</ref> The project was initiated partly in response to an [[ITV (TV network)|ITV]] documentary series ''The Mighty Micro'', in which [[Christopher Evans (computer scientist)|Christopher Evans]] of the UK's [[National Physical Laboratory (United Kingdom)|National Physical Laboratory]] predicted the coming [[microcomputer revolution]] and its effect on the economy, industry, and lifestyle of the United Kingdom.<ref name="LEM">{{Cite web |last=Hormby |first=Thomas |date=8 February 2007 |title=Acorn and the BBC Micro: From education to obscurity |url=http://lowendmac.com/2007/acorn-and-the-bbc-micro-from-education-to-obscurity/ |url-status=live |archive-url=https://web.archive.org/web/20070303004213/http://lowendmac.com/orchard/07/0228.html |archive-date=3 March 2007 |access-date=1 March 2007 |website=Low End Mac}}</ref>

The BBC Computer Literacy Project had been conceived by the BBC's [[BBC Education|Continuing Education Television]] department. With funding from the [[Manpower Services Commission]], the department undertook research which culminated in the publication of the Microelectronics report in 1979, which was issued to all United Kingdom MPs. The underlying philosophy from the report was that people should learn how to use and control computers, rather than feel dominated by them.<ref>{{Cite book |last=Albury |first=R. |url=https://clp.bbcrewind.co.uk/media/BBC-Microelectronic-government-submission.pdf |title=Microelectronics. A report prepared by Robert Albury and David Allen of the BBC Continuing Education Department for the Manpower Services Commission. |last2=Allen |first2=D. |date=1979 |publisher=[[BBC Education|BBC Continuing Education Department]] |location=London |access-date=5 March 2025}}</ref><ref>{{Cite web |last=Content |first=BBC Archive |title=BBC Computer Literacy Project |url=https://clp.bbcrewind.co.uk/history |access-date=2025-03-05 |website=clp.bbcrewind.co.uk |language=en}}</ref>

The BBC wanted to base its project on a [[microcomputer]] capable of performing various tasks which they could then demonstrate in the TV series ''[[The Computer Programme]]''. The list of topics included [[computer programming|programming]], [[computer graphics|graphics]], sound and music, [[teletext]], controlling external hardware, and [[artificial intelligence]]. It developed an ambitious specification for a BBC computer, and discussed the project with several companies including [[Acorn Computers]], [[Sinclair Research]], Newbury Laboratories, [[Tangerine Computer Systems]], and [[Dragon Data]].<ref name="LEM" />

The introduction of a specific microcomputer to a more general computer literacy initiative was a topic of controversy, however, with criticism aimed at the BBC for promoting a specific commercial product and for going beyond the "traditional BBC pattern" of promoting existing information networks of training and education providers. Accusations were even levelled at the Department of Industry for making the BBC "an arm of Government industrial policy" and using the Computer Literacy Project as a way of "funding industry through the back door", obscuring public financial support on behalf of a government that was ostensibly opposed to subsidising industry.<ref name="pcw198205_auntie">{{Cite magazine |last=Peltu |first=Malcolm |date=May 1982 |title=Has the BBC Microcomputer sent Auntie off the straight and narrow? |url=https://archive.org/details/PersonalComputerWorld1982-05/page/118/mode/2up |access-date=27 September 2021 |magazine=[[Personal Computer World]] |pages=118–119 |volume=5 |issue=5}}</ref>

The Acorn team had already been working on a successor to their existing [[Acorn Atom|Atom]] microcomputer. Known as the ''Proton'', it included better graphics and a faster 2&nbsp;MHz [[MOS Technology 6502]] [[central processing unit]]. The machine was only at the design stage at the time, and the Acorn team, including [[Steve Furber]] and [[Sophie Wilson]], had one week to build a working prototype from the sketched designs.<ref name="pcw laing 2004">{{Cite magazine |last=Laing |first=Gordon |date=22 March 2004 |title=Retro computing |url=http://www.computeractive.co.uk/ca/pc-help/1914141/retro-computing |url-status=dead |archive-url=https://web.archive.org/web/20120820023753/http://www.computeractive.co.uk/ca/pc-help/1914141/retro-computing |archive-date=20 August 2012 |access-date=10 April 2012 |magazine=[[Personal Computer World]] }}</ref> The team worked through the night to get a working Proton together to show the BBC.<ref name="PC Pro">{{Cite magazine |last=Collins |first=Barry |date=7 August 2006 |title=BBC Basic: the people's language |url=http://www.pcpro.co.uk/features/91575/bbc-basic-the-peoples-language.html |url-status=live |archive-url=https://web.archive.org/web/20070210052202/http://www.pcpro.co.uk/features/91575/bbc-basic-the-peoples-language.html |archive-date=10 February 2007 |access-date=7 February 2007 |magazine=[[PC Pro]]}}</ref> Although the BBC expected a computer with the [[Zilog Z80]] CPU and [[CP/M]] operating system, not the Proton's 6502 CPU and proprietary operating system,{{r|furber20150325}} the Proton was the only machine to fulfil the BBC's specification, actually exceeding it in nearly every parameter.<ref name="LEM" />

Based on the Proton prototype, the BBC signed a contract with Acorn as early as February 1981; by June the BBC Micro's specifications and pricing were decided.{{r|reghardware}} As a concession to the BBC's expectation of "industry standard" compatibility with CP/M, apparently under the direction of John Coll, the [[Tube (BBC Micro)|Tube]] interface was incorporated into the design, enabling a Z80 second processor to be added.<ref name="acornuser199610_history">{{Cite magazine |last=Singleton |first=Alex |date=October 1996 |title=From BBC to Oracle |url=https://archive.org/details/AcornUser173-Oct96/page/n37/mode/2up |access-date=18 March 2021 |magazine=Acorn User |pages=38–40}}</ref> A new contract between Acorn and BBC Enterprises was agreed in 1984 for another four-year term, with other manufacturers having tendered for the deal. An Acorn representative admitted that the BBC Model B would not be competitive throughout the term of the renewed contract, and that a successor would emerge.<ref name="pcw198409_acorn">{{Cite magazine |last=Sanders |first=Jerry |date=September 1984 |title=Acorn first past the post |url=https://archive.org/details/PersonalComputerWorld1984-09/page/101/mode/1up |access-date=26 April 2021 |magazine=Personal Computer World |page=101}}</ref>

The OS [[read-only memory|ROM]] v1.0 contains the following ASCII credits string (code [https://pastebin.com/Uft7eyh8 here]):

<blockquote><pre>(C) 1981 Acorn Computers Ltd.Thanks are due to the following contributors to the development of the BBC Computer (among others too numerous to mention):- David Allen,Bob Austin,Ram Banerjee,Paul Bond,Allen Boothroyd,Cambridge,Cleartone,John Coll,John Cox,Andy Cripps,Chris Curry,6502 designers,Jeremy Dion,Tim Dobson,Joe Dunn,Paul Farrell,Ferranti,Steve Furber,Jon Gibbons,Andrew Gordon,Lawrence Hardwick,Dylan Harris,Hermann Hauser,Hitachi,Andy Hopper,ICL,Martin Jackson,Brian Jones,Chris Jordan,David King,David Kitson,Paul Kriwaczek,Computer Laboratory,Peter Miller,Arthur Norman,Glyn Phillips,Mike Prees,John Radcliffe,Wilberforce Road,Peter Robinson,Richard Russell,Kim Spence-Jones,Graham Tebby,Jon Thackray,Chris Turner,Adrian Warner,Roger Wilson,Alan Wright.</pre></blockquote>

Additionally, the last bytes of the BASIC [[read-only memory]] (ROM; v2 and v4) include the word "Roger", which is a reference to [[Sophie Wilson]] whose name at the time was Roger Wilson.<ref>{{Cite web |last=Russell |first=R. T. |title=A History of BBC BASIC |url=https://www.bbcbasic.co.uk/bbcbasic/history.html |url-status=live |archive-url=https://web.archive.org/web/20070125200740/http://www.bbcbasic.co.uk:80/bbcbasic/history.html |archive-date=25 January 2007 |access-date=12 July 2021 |website=bbcbasic.co.uk}}</ref>

== Market impact ==
[[File:Acorn BBC B microcomputer - keyboard.jpg|thumb|Keyboard of a {{nowrap|Model B}}, one of two very similar designs used on the model]]
The machine was released as the BBC Microcomputer on 1 December 1981, although production problems pushed delivery of the majority of the initial run into 1982.<ref name="reghardware">{{Cite news |last=Smith |first=Tony |date=30 November 2011 |title=The BBC Micro turns 30 |url=http://www.reghardware.com/2011/11/30/bbc_micro_model_b_30th_anniversary/ |url-status=live |archive-url=https://web.archive.org/web/20111212044749/http://www.reghardware.com/2011/11/30/bbc_micro_model_b_30th_anniversary/ |archive-date=12 December 2011 |access-date=12 December 2011 |publisher=The Register Hardware}}</ref><ref name="bbc-1dec2011">{{Cite news |date=1 December 2011 |title=The BBC Microcomputer and me, 30 years down the line |url=https://www.bbc.co.uk/news/technology-15969065 |url-status=live |archive-url=https://web.archive.org/web/20111211001838/http://www.bbc.co.uk/news/technology-15969065 |archive-date=11 December 2011 |access-date=13 December 2011 |work=BBC News}}</ref>{{better source needed |date=December 2021|reason=The Register article brings up the release date but there is no indication of where it comes from, such as an event or announcement that might have occurred and been reported in the media. Indeed, the very reason why the BBC News article was introduced here was to note that "late 1981", as appeared previously on this page, was the most accurate anyone was willing to be.}} Nicknamed "the Beeb",<ref name="bbc creators reunite">{{Cite news |date=20 March 2008 |title='Beeb' creators reunite at museum |url=http://news.bbc.co.uk/1/hi/technology/7303288.stm |url-status=live |archive-url=https://web.archive.org/web/20080323180154/http://news.bbc.co.uk/1/hi/technology/7303288.stm |archive-date=23 March 2008 |access-date=23 March 2008 |work=BBC News}}</ref> it was popular in the UK, especially in the educational market; about 80% of British schools had a BBC microcomputer.<ref name="iiasa">{{Cite report |url=http://www.iiasa.ac.at/Admin/PUB/Documents/WP-86-052.pdf |title=Educational policies: an international review |last=Vasko |first=Tibor |last2=Dicheva |first2=Darina |date=September 1986 |publisher=International Institute for Applied Systems Analysis |location=Austria |page=7 |access-date=12 December 2011 |archive-url=https://web.archive.org/web/20120531051641/http://www.iiasa.ac.at/Admin/PUB/Documents/WP-86-052.pdf |archive-date=31 May 2012 |url-status=dead}}</ref><ref name="wired-mar2011">{{Cite magazine |last=McClelland |first=David |date=18 March 2011 |title=How a BBC Micro shaped the course of GeekDad's life |url=https://www.wired.co.uk/news/archive/2011-03/18/bbc-micro |url-status=dead |archive-url=https://web.archive.org/web/20111230170636/http://www.wired.co.uk/news/archive/2011-03/18/bbc-micro |archive-date=30 December 2011 |magazine=Wired }}</ref>

''[[Byte (magazine)|Byte]]'' called the BBC Micro Model B "a no-compromise computer that has many uses beyond self-instruction in computer technology". It called the [[Tube (BBC Micro)|Tube interface]] "the most innovative feature" of the computer, and concluded that "although some other British microcomputers offer more features for a given price, none of them surpass the BBC ... in terms of versatility and expansion capability".<ref name="williams198301">{{Cite magazine |last=Williams |first=Gregg |date=January 1983 |title=Microcomputer, British Style / The Fifth Personal Computer World Show |url=https://archive.org/stream/byte-magazine-1983-01/1983_01_BYTE_08-01_Looking_Ahead#page/n41/mode/2up |access-date=19 October 2013 |magazine=[[Byte (magazine)|Byte]] |pages=40 |volume=8 |issue=1}}</ref> As with [[Sinclair Research]]'s [[ZX Spectrum]] and [[Commodore International]]'s [[Commodore 64]], both released the next year, in 1982, demand greatly exceeded supply. For some months, there were long delays before customers received the machines they had ordered.

=== Export initiatives ===
Efforts were made to market the machine in the United States and West Germany.<ref name="nytimes British race">{{Cite news |last=Feder |first=Barnaby J. |date=27 February 1984 |title=British race is on in microcomputers |url=https://www.nytimes.com/1984/02/27/business/british-race-is-on-in-microcomputers.html?pagewanted=2 |url-access=limited |url-status=live |archive-url=https://web.archive.org/web/20130518093300/http://www.nytimes.com/1984/02/27/business/british-race-is-on-in-microcomputers.html?pagewanted=2 |archive-date=18 May 2013 |access-date=12 December 2011 |work=The New York Times  |quote=Sales neared $60 million in the second half of last year as efforts began to sell to schools in the United States and Germany.}}</ref> Acorn's strategy in the US focused on the education market, worth a reported {{nowrap|$700 million}}, by offering the BBC Micro in an upgraded form of the Model B with an expanded ROM, speech synthesis hardware, and built-in Econet interface for a price of $995, complementing this with the provision of software and materials designed to support teaching and to encourage adoption by teachers "fearful" of computers or skeptical of the role of computers in the curriculum.<ref name="compute198312_dignazio">{{Cite magazine |last=D'Ignazio |first=Fred |date=December 1983 |title=The Electronic Chalkboards: The BBC And The Powerpad |url=https://archive.org/details/1983-12-compute-magazine/page/n159/mode/1up |access-date=31 May 2023 |magazine=Compute! |pages=160, 164, 166}}</ref>

By October 1983, the US operation reported that American schools had placed orders with it totalling {{nowrap|$21 million}}.<ref name="nytimes ">{{Cite news |date=7 October 1983 |title=Acorn Computer Makes U.S. Debut |url=https://www.nytimes.com/1983/10/07/business/acorn-computer-makes-us-debut.html |url-access=limited |url-status=live |archive-url=https://web.archive.org/web/20130518081150/http://www.nytimes.com/1983/10/07/business/acorn-computer-makes-us-debut.html |archive-date=18 May 2013 |access-date=12 December 2011 |work=The New York Times  |quote=Acorn Computers Ltd., which dominates the educational computer market in Britain, introduced its BBC microcomputer in the United States yesterday and said it had already received $21 million in orders from American schools. [...] the Acorn Computer Corporation, the British company's United States subsidiary.}}</ref> In one deployment in Lowell, Massachusetts valued at $177,000, 138 BBC Micros were installed in eight of the 27 schools in the city, with the computer's networking capabilities, educational credentials, and the availability of software with "high education quality" accompanied by "useful lesson plans and workbooks" all given as reasons for selecting Acorn's machine in preference to the competition from IBM, [[Apple Inc.|Apple]], and Commodore.<ref name="misweek19840404_acorn">{{Cite magazine |last=Dooley |first=Bill |date=4 April 1984 |title=Lowell's Tots Getting CPUs |url=https://archive.org/details/sim_mis-week_1984-04-04_5_14/page/32/mode/1up |access-date=15 February 2022 |magazine=Management Information Systems Week |pages=32}}</ref> Another deployment in Phoenix, Arizona valued at $174,697 saw 175 BBC Micros installed, with the local Acorn dealer predicting sales worth {{nowrap|$2 million}} in the next two years, of which around 85 to 90 percent would be made into education, the remainder going to the small business market. In early 1984, Acorn claimed a US network of more than 1,000 dealers,<ref name="micromarketworld19840206_acorn">{{Cite magazine |date=6 February 1984 |title=Two firms in U.S. agree to market BBC from Acorn |url=https://archive.org/details/sim_micro-marketworld_1984-02-06_7_3/page/n18/mode/1up |access-date=23 August 2022 |magazine=Micro Marketworld |pages=17}}</ref> also reporting "over {{nowrap|$50 million}} worth of education orders for the BBC Micro system" for which 200 educational titles were being offered.<ref name="abcomputing198405">{{Cite magazine |date=May–June 1984 |title=Acorn News |magazine=A&B Computing |pages=8}}</ref>

In October 1984, while preparing a major expansion of its US dealer network, Acorn claimed sales of 85 per cent of the computers in British schools, and delivery of 40,000 machines per month.<ref name="infoworld-8oct84">{{Cite magazine |last=Caruso |first=Denise |date=8 October 1984 |title=Acorn plucks former Apple reps |url=https://books.google.com/books?id=Ci8EAAAAMBAJ&pg=PA14 |magazine=[[InfoWorld]] |page=14 |volume=6 |issue=41}}</ref> That December, Acorn stated its intention to become the market leader in US educational computing.<ref name="nytimes British coming">{{cite news |last=Lewis |first=Peter H. |title=Peripherals; The British are Coming |work=The New York Times |date=18 December 1984 |url=https://www.nytimes.com/1984/12/18/science/peripherals-the-british-are-coming.html |access-date=12 December 2011 |quote=At a consumer electronics show in London last week, a company official said Acorn intends to rectify the situation by becoming the best-selling educational computer in America. [...] Most important to teachers, the Acorn is already set up for local area networking, allowing all computers in a classroom to be linked together. |url-status=live |archive-url=https://web.archive.org/web/20130518084852/http://www.nytimes.com/1984/12/18/science/peripherals-the-british-are-coming.html |archive-date=18 May 2013  |url-access=limited}}</ref> ''[[The New York Times]]'' considered the inclusion of [[local area networking]] to be of prime importance to teachers.<ref name="nytimes British coming" /> The operation resulted in advertisements by at least one dealer in ''[[Interface Age]]'' magazine,<ref>{{cite web |last=Edwards |first=Benj |title=&#91; Retro Scan of the Week &#93; The BBC Microcomputer |publisher=Vintage Computing and Gaming |date=17 May 2010 |url=http://www.vintagecomputing.com/index.php/archives/657 |access-date=23 May 2011 |quote=This scan of an American BBC Microcomputer ad [...] |url-status=live |archive-url=https://web.archive.org/web/20110717205850/http://www.vintagecomputing.com/index.php/archives/657 |archive-date=17 July 2011}}</ref> but ultimately the attempt failed.<ref name="acornuser198602">{{cite magazine |url=https://archive.org/details/AcornUser043-Feb86/page/n10/mode/1up |title=Acorn moves out of US |magazine=Acorn User |date=February 1986 |access-date=26 September 2020 |pages=9}}</ref>

The success of the machine in the UK was due largely to its acceptance as an "educational" computer – UK schools used BBC Micros to teach [[computer literacy]], information technology skills.<ref name="LEM" /> Acorn became more known for its {{nowrap|BBC Model B}} computer than for its other products.<ref name="smartcompany sadauskas">{{cite news |last=Sadauskas |first=Andrew |title=BBC Micro B lives on: Strong growth for ARM after increased tablet and smartphone use |newspaper=SmartCompany |date=27 July 2012 |url=http://www.smartcompany.com.au/information-technology/050914-bbc-micro-b-lives-on-strong-growth-for-arm-after-increased-tablet-and-smartphone-use.html |access-date=7 August 2012 |url-status=live |archive-url=https://web.archive.org/web/20120728230947/http://www.smartcompany.com.au/information-technology/050914-bbc-micro-b-lives-on-strong-growth-for-arm-after-increased-tablet-and-smartphone-use.html |archive-date=28 July 2012}}</ref> Some Commonwealth countries, including [[India]], started their own computer literacy programmes around 1984.<ref name="nag1989">{{Cite journal |last=Nag |first=B |date=1989 |title=Informatics Education in India: The CLASS Project For Secondary Students |url=http://link.springer.com/10.1057/hep.1989.76 |journal=Higher Education Policy |language=en |volume=2 |issue=4 |pages=71–72 |doi=10.1057/hep.1989.76 |s2cid=57786190 |issn=0952-8733|url-access=subscription }}</ref> Intending to avoid "[[re-inventing the wheel]]", such efforts adopted the BBC Micro in order to take immediate advantage of the extensive range of software already developed under the United Kingdom's own literacy initiative, proposing that software tailored for local requirements would ultimately also be developed.<ref name="class1984">{{cite book |url=https://archive.org/details/dli.ernet.18885/mode/2up |title=CLASS – Computer Literacy and Studies in Schools |publisher=National Council of Educational Research and Training |date=June 1984 |access-date=29 October 2022}}</ref>{{rp |pages=71–72}} A clone of the BBC Micro was produced by Semiconductor Complex Limited and named the SCL Unicorn.<ref>{{cite news |last=Tank |first=Andrew |title=India's Schoolchildren Have Got Class |work=[[Computer Weekly]] |pages=29 |publisher=[[InfoTrac|General Reference Center Gold]] |date=10 April 1986}}</ref><ref>{{cite journal |author=Keval J. Kumar |title=Media education and computer literacy in India: The need for an integrated 'compunication |journal=International Communication Gazette |volume=40 |issue=3 |pages=183–202 |year=1987 |doi=10.1177/001654928704000303|s2cid=144406303}}</ref><ref>{{cite web |title=SCL Unicorn |publisher=computinghistory.org.uk |url=http://www.computinghistory.org.uk/cgi-bin/sitewise.pl?act=det&p=4930 |url-status=dead |archive-url=https://web.archive.org/web/20100821125823/http://www.computinghistory.org.uk/cgi-bin/sitewise.pl?act=det&p=4930 |archive-date=21 August 2010}}</ref> Another Indian computer manufacturer, Hope Computers Pvt Ltd, made a BBC Micro clone called the Dolphin. Unlike the original BBC Micro, the Dolphin featured blue function keys.<ref>{{Cite tweet |user=sandeeproy1 |date=8 February 2022 |access-date=2022-05-18 |number=1490885752892260354 |title=My first computer was a BBC Micro! 1984. Still have it. (This photo taken in 2021)}}</ref>

Production agreements were made with both SCL in India and distributor Harry Mazal in Mexico for the assembly of BBC Micro units from kits of parts, leading to full-scale manufacturing, with SCL also planning to fabricate the 6502 CPU under licence from Rockwell.<ref name="acornuser198411">{{cite magazine |url=https://archive.org/details/AcornUser028-Nov84/page/n11/mode/1up |title=India takes on Beeb assembly |magazine=Acorn User |date=November 1984 |access-date=25 October 2020 |pages=10}}</ref> According to reporting from early 1985, "several thousand Beebs a month" were being produced in India. Meanwhile, the eventual production arrangement in Mexico involved local manufacturer Datum (a company founded by Harry Mazal and others, initially to act as [[International Computers Limited|ICL's]] Mexican distributor<ref name="misweek19840627_datum">{{cite magazine |url=https://archive.org/details/sim_mis-week_1984-06-27_5_26/page/43/mode/1up |title=ICL Sells Mexico Subsidiary Share |magazine=Management Information Systems Week |date=27 June 1984 |access-date=27 June 2023 |pages=43}}</ref>), aiming to assemble 2000 units per month by May 1985, with the initial assembly intended to lead to the manufacture of all aspects of the machines apart from Acorn's proprietary ULA components. Such machines were intended for the Mexican and South American markets, potentially also appealing to those south-western states of the US having large Spanish-speaking populations.<ref name="acornuser198504">{{cite magazine |url=https://archive.org/details/AcornUser033-Apr85/page/n18/mode/1up |title=Mexico deal gives Beeb south-of-border base |magazine=Acorn User |date=April 1985 |access-date=26 October 2020 |pages=17}}</ref> Ultimately, upon Acorn's withdrawal from the US in 1986, Datum would continue manufacturing at a level of 7000 to 8000 Spanish-language machines per year for the North and South American markets.<ref name="acornuser198602" />

=== Pricing and adoption ===
The initial strategy for the BBC's computer literacy endeavour involved the marketing of the "Acorn Proton-based BBC microcomputer for less than £200".<ref name="yourcomputer198106_proton">{{cite magazine |url=https://archive.org/details/your-computer-magazine-1981-06/page/n31/mode/2up |title=BBC's Proton project and the nuclear family |magazine=Your Computer |date=June 1981 |access-date=9 December 2021 |last1=Hayman |first1=Martin |pages=36–39}}</ref> The Model A and the Model B were initially priced at £235 and £335 respectively, but increased almost immediately to £299 and £399 due to higher costs.<ref name="computing-today-review">{{Cite magazine |magazine=Computing Today |date=March 1982 |title=BBC Micro – Review |url=http://www.stairwaytohell.com/articles/cr-BBCMicro-CToday.html |access-date=12 December 2011}}</ref> The {{nowrap|Model B}} price of nearly £400 was roughly £1200<ref name="techworld geeks rejoice">{{cite news |last=Dunn |first=John E |title=Geeks rejoice as BBC Micro celebrates 30-year anniversary |work=[[Techworld]] |date=1 December 2011 |url=http://news.techworld.com/personal-tech/3322299/bbc-micro-celebrates-30-year-anniversary/ |access-date=4 March 2012 |url-status=live |archive-url=https://web.archive.org/web/20111204030606/http://news.techworld.com/personal-tech/3322299/bbc-micro-celebrates-30-year-anniversary/ |archive-date=4 December 2011}}</ref> (€1393)<ref name="techcentral celebrates thirtieth">{{cite news |title=BBC Micro celebrates thirtieth anniversary |work=TechCentral.ie |publisher=[[PC Live!]] |date=2 December 2011 |url=http://www.techcentral.ie/article.aspx?id=17881 |archive-url=https://archive.today/20130217233036/http://www.techcentral.ie/article.aspx?id=17881 |url-status=dead |archive-date=17 February 2013 |access-date=4 March 2012}}</ref> in 2011 prices – thirty years after its launch – or around £{{Inflation|UK|400|1981|r=-2}} today. Acorn anticipated total sales to be around 12,000 units, but eventually more than 1.5 million BBC Micros were sold.<ref name="wired-mar2011" /><ref>{{cite news |title=Home computing pioneer honoured |work=BBC News |date=29 December 2007 |url=http://news.bbc.co.uk/2/hi/technology/7162935.stm |access-date=26 April 2010 |url-status=live |archive-url=https://web.archive.org/web/20100807003624/http://news.bbc.co.uk/2/hi/technology/7162935.stm |archive-date=7 August 2010}}</ref> The cost of the BBC Models was high compared to competitors such as the ZX Spectrum and the Commodore 64, and from 1983 on, Acorn attempted to counter this by producing a simplified but largely compatible version intended for home use, complementing the use of the BBC Micro in schools: the 32K [[Acorn Electron]].<ref name="acornuser198307">{{cite magazine |url=https://archive.org/details/AcornUser012-Jul83/page/n6/mode/1up |title=Electron set for battle at £199 |magazine=Acorn User |date=July 1983 |access-date=26 September 2020 |pages=5}}</ref>

=== The ITV Micro ===
The involvement of the BBC in microcomputing also initiated tentative plans by the independent television companies of the [[ITV (TV network)|ITV network]] to introduce their own initiative and rival computing system, with a CP/M-based system proposed by Transam Computers under consideration for such an initiative by the Independent Television Companies Association at a late 1983 meeting. The proposed machine would have been priced at £399, matching that of the BBC Model B, and was reported as offering 64&nbsp;KB of RAM, a disc interface, and serial and parallel interfaces, itself being a "low-cost development" of an existing machine, the Transam Tuscan, which included dual floppy drives and cost £1,700.<ref name="popcompweekly19831208_itv">{{cite news |url=https://archive.org/details/popular-computing-weekly-1983-12-08/mode/1up |title=New ITV venture to rival BBC? |work=Popular Computing Weekly |date=8 December 1983 |access-date=23 October 2021 |pages=1, 5}}</ref>

This proposal was voted down by the ITV companies, citing a possible contravention of the companies' obligations under broadcasting regulations prohibiting sponsorship, along with concerns about a conflict of interest with advertisers of computer products.<ref name="popcompweekly19831222_itv">{{cite news |url=https://archive.org/details/popular-computing-weekly-1983-12-22/page/n4/mode/1up |title=ITV says 'No' to micro |work=Popular Computing Weekly |date=22 December 1983 |access-date=23 October 2021 |pages=5}}</ref> Despite denials of involvement with ITV from Prism Microproducts, the company had already been pursuing a joint venture with Transam on a product rumoured to be under consideration by the broadcasting group.<ref name="pcn19840104_itv">{{cite news |url=https://archive.org/details/mag_PersonalComputerNews042-04Jan1984/page/n5/mode/1up |title=ITV plan dies |work=Personal Computer News |date=4 January 1984 |access-date=23 October 2021 |pages=4}}</ref> This product, a business system subsequently known as the Wren,<ref name="pcw198403_wren">{{cite magazine |url=https://archive.org/details/PersonalComputerWorld1984-03/page/24/mode/1up |title=Newsprint |magazine=Personal Computer World |date=March 1984 |access-date=22 October 2021 |last1=Bright |first1=Peter |pages=23}}</ref> had reportedly been positioned as such an "ITV Micro" towards the end of 1983, also to be offered in a home variant with [[ORACLE (teletext)|ORACLE]] teletext reception capabilities. However, not all ITV franchise holders were equally enthusiastic about scheduling programmes related to microcomputing or about pursuing a computer retailing strategy.<ref name="pcw198401_itv">{{cite magazine |url=https://archive.org/details/PersonalComputerWorld1984-01/page/123/mode/1up |title=No advertising, please |magazine=Personal Computer World |date=January 1984 |access-date=23 October 2021 |last1=Kewney |first1=Guy |pages=123–124}}</ref>

== Description ==

=== Hardware features: Models A and B ===
[[File:BBC Micro rear.jpeg|right|thumb|320px|Rear of the BBC Micro. Ports from left to right: [[UHF television broadcasting|UHF out]], [[Composite video|video out]], [[Analog RGB|RGB]], [[RS-423]], [[cassette tape]], analogue in and [[Econet]].]]

A key feature of the BBC Micro's design is the high-performance [[random-access memory]] (RAM) it is equipped with. A common design note in [[MOS Technology 6502|6502]]-based computers of the era was to run the RAM at twice the clock rate as the CPU. This allowed a separate [[video display controller]] to access memory while the CPU was busy processing the data just read. In this way, the CPU and graphics driver could share access to RAM through careful timing. This technique was used, for example, on the [[Apple II Plus]] and the early [[Commodore International|Commodore]] models.<ref name="reghardware" /><ref name="mikestirling-fpga">{{Cite web |last=Stirling |first=Mike |date=21 August 2011 |title=BBC Micro on an FPGA |url=http://mikestirling.co.uk/bbc-micro-on-an-fpga/|access-date=11 June 2012 |url-status=live |archive-url=https://web.archive.org/web/20121220040826/http://mikestirling.co.uk/bbc-micro-on-an-fpga/ |archive-date=20 December 2012}}</ref><ref name="computing-today-review" />

The BBC machine, however, was designed to run at the faster CPU speed, 2&nbsp;[[megahertz|MHz]], double that of these earlier machines. In this case, [[bus contention]] is normally an issue, as there is not enough time for the CPU to access the memory during the period when the video hardware is idle. Some machines of the era accept the inherent performance hit, as was the case for the [[Amstrad CPC]], [[Atari 8-bit computers]], and to a lesser extent the [[ZX Spectrum]]. Others, like the [[MSX]] systems, used entirely separate pools of memory for the CPU and video, slowing access between the two.

Furber believed that the Acorn design should have a [[flat memory model]] and allow the CPU and video system to access the bus without interfering with each other.{{r|furber20150325}} To do so, the RAM had to allow four million access cycles per second. [[Hitachi]] was the only company considering a [[Dynamic random-access memory|DRAM]] which ran at that speed, the HM4816. To equip the prototype machine, the only four 4816s in the country were hand-carried by the Hitachi representative to Acorn.<ref>{{Cite web |last= Fairbairn |first= Douglas |date= 31 January 2012 |title= Oral History of Sophie Wilson |url= http://archive.computerhistory.org/resources/access/text/2012/06/102746190-05-01-acc.pdf|access-date= 2 February 2016 |url-status= dead |archive-url= https://web.archive.org/web/20160303221351/http://archive.computerhistory.org/resources/access/text/2012/06/102746190-05-01-acc.pdf |archive-date= 3 March 2016|df= dmy-all}}</ref>

The National Semiconductor 81LS95 [[multiplexer]] was needed for the high memory speed. Furber recalled that competitors came to Acorn offering to replace the component with their own, but "none of them worked. And we never knew why. Which of course, means we didn't know why the National Semiconductor one ''did'' work correctly. And a million and a half BBC Micros later, it was still working, and I still didn't know why". Another mystery was the 6502's [[bus (computing)|data bus]]. The prototype BBC Micro exceeded the CPU's specifications, causing it to fail. The designers found that putting a finger on a certain place on the motherboard caused the prototype to work. Acorn put a [[resistor]] pack across the data bus, which Furber described as {{"'}}the engineer's finger' and again, we have no idea why it's necessary, and a million and a half machines later it's still working, so nobody asked any questions".{{r|furber20150325}}

The Model A shipped with 16&nbsp;[[kibibyte|KB]] of user RAM, while the Model B had 32&nbsp;KB. Extra ROMs could be fitted (four on the PCB or sixteen with expansion hardware) and accessed via [http://mdfs.net/Docs/Comp/BBC/AllMem paged memory].

The machines included three video ports, one with an [[RF modulator]] sending out a signal in the [[Ultra high frequency|UHF]] band, another sending [[composite video]] suitable for connection to [[computer monitor]]s, and a separate [[Component video|RGB video]] port. The separate RGB video out socket was an engineering requirement from the BBC to allow the machine to directly output a broadcast quality signal for use within television programming; it was used on episodes of ''[[The Computer Programme]]'' and ''[[Making the Most of the Micro]]''.

The computer included several [[input/output]] (I/O) interfaces: [[Serial port|serial]] and [[Parallel port|parallel]] printer ports, an [[8-bit computing|8-bit]] general purpose digital I/O port, a port offering four [[Analog signal|analogue]] inputs, a light pen input, and an expansion connector (the "1&nbsp;MHz bus") which enabled other hardware to be connected. An [[Econet]] network interface and a disk drive interface were available as options. All motherboards had space for the electronic components, but Econet was rarely installed.

Additionally, an Acorn proprietary interface named the "[[Tube (BBC Micro)|Tube]]" allowed a second processor to be added. Three models of second processor were offered by Acorn, based on the [[BBC Micro expansion unit#6502 Second Processor|6502]], [[BBC Micro expansion unit#Z80 Second Processor|Z80]] and [[BBC Micro expansion unit#32016 Second Processor|32016]] CPUs. The Tube was used for third-party add-ons, including a Z80 board and [[hard disk drive]] from Torch that allowed the BBC machine to run CP/M programs.

Separate pages, each with a codename, are used to control the access to the I/O:<ref>[BBC Microcomputer Service Manual]</ref>
{| class="wikitable"
! Codename !! Page !! Description
|-
| FRED
| 0xFC00 – 0xFCFF
| 1&nbsp;MHz bus
|-
| JIM
| 0xFD00 – 0xFDFF
| 1&nbsp;MHz bus / paged RAM
|-
| SHEILA
| 0xFE00 – 0xFEFF
| Mapped I/O for resident hardware – video, cassette, sound, interrupts
|}

The Tube interface allowed Acorn to use BBC Micros with [[ARM architecture|ARM]] CPUs as software development machines when creating the [[Acorn Archimedes]]. This resulted in the ARM development kit for the BBC Micro in 1986, priced at around £4000.<ref>{{cite web |url=http://www.mcmordie.co.uk/acornhistory/archist.shtml |title=The start of the revival – The ARM and the Archimedes (1986 to 1988)|website=www.mcmordie.co.uk|access-date=15 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20160711004947/http://www.mcmordie.co.uk/acornhistory/archist.shtml |archive-date=11 July 2016}}</ref> From 2006, a kit with an [[ARM7#ARM7TDMI|ARM7TDMI]] CPU running at 64&nbsp;MHz, with as much as 64&nbsp;MB of RAM, was released for the BBC Micro and Master, using the Tube interface to upgrade the 8-bit micros to 32-bit RISC machines.<ref>{{cite web |url=http://www.drobe.co.uk/article.php?id=1557 |title=Drobe.co.uk archives|website=www.drobe.co.uk |url-status=deviated |archive-url=https://web.archive.org/web/20131219044636/http://www.drobe.co.uk/riscos/artifact1557.html |archive-date=19 December 2013}}</ref> Among the software that operated on the Tube are an enhanced version of the ''[[Elite (video game)|Elite]]'' video game and a [[computer-aided design]] system that required a second 6502 CPU and a 3-dimensional joystick named a "Bitstik"[http://chrisacorns.computinghistory.org.uk/8bit_Upgrades/Acorn_BitStik.html].

The Model A and the Model B were built on the same [[printed circuit board]] (PCB), and a Model A can be upgraded to a Model B. Users wishing to operate Model B software need to add the extra RAM and the user/printer [[MOS Technology 6522]] VIA (which many games use for timers) and snip a link, a task that can be achieved without soldering. To do a full upgrade with all the external ports requires soldering the connectors to the motherboard. The original machines shipped with "OS 0.1", with later updates advertised in magazines, supplied as a clip-in integrated circuit, with the last official version being "OS 1.2". Variations in the Acorn OS exist as a result of home-made projects and modified machines can still be bought on Internet auction sites such as [[eBay]] as of 2011.

The BBC Model A was phased out of production with the introduction of the [[Acorn Electron]], with chairman Chris Curry stating at the time that Acorn "would no longer promote it" (the Model A).<ref name="acornuser198307" />

Early BBC Micros used [[Power supply#Linear regulated power supply|linear power supplies]] at the insistence of the BBC, which, as a broadcaster, was cautious about [[electromagnetic interference]]. The supplies were unreliable, and after a few months the BBC allowed [[Switched-mode power supply|switched-mode]] units.{{r|furber20150325}}

An apparent oversight in the manufacturing process resulted in many Model Bs producing a constant buzzing noise from the built-in speaker. This fault can be rectified partly by soldering a resistor across two pads.<ref>{{cite web |url=http://www.sprow.co.uk/bbc/doctor.htm#bzzzt |title=Sprow's webpages – cyber doctor for poorly beebs|website=www.sprow.co.uk|access-date=15 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20171006014606/http://www.sprow.co.uk/bbc/doctor.htm#bzzzt |archive-date=6 October 2017}}</ref>

There are five developments of the main BBC Micro circuit board that addressed various issues through the model's production, from 'Issue 1' through to 'Issue 7' with variants 5 and 6 not being released. The 1985 'BBC Microcomputer Service Manual' from Acorn documents the details of the technical changes.

Per [[Watford Electronics]] comments in their '32K Ram Board Manual':
{{Blockquote|Early issue BBCs (Issue 3 circuit boards and before) are notorious for out of specification timings. If problems occur with this sort of machine, the problem can generally be cured by the use of either a Rockwell 6502A CPU chip, or by replacing IC14 (a 74LS245) with either another 74LS245 or the faster 74ALS245.<ref>[http://8bs.whelks.com/othrdnld/manuals/hardware/we32kshadowram_pdf.zip Watford Electronics 32K Ram Board Manual] {{webarchive |url=https://web.archive.org/web/20161011175337/http://8bs.whelks.com/othrdnld/manuals/hardware/we32kshadowram_pdf.zip |date=11 October 2016}}</ref>}}

==== Export models ====
[[File:Interface age scan nov 1983 p30 bbc micro ad.jpg|thumb|upright|Advert in ''Interface Age'' magazine, November 1983, {{'}}''The BBC Microcomputer Is Here!''{{'}}]]
Two export models were developed: one for the US,<ref name="scholten-usbbc">{{cite web
 |url=http://wouter.bbcmicro.net/pictures/computer/usa_bbc/index.html
 |title=USA model BBC micro
 |access-date=28 March 2008
|last=Scholten
 |first=Wouter
 |date=17 June 2007
|url-status=dead
 |archive-url=https://web.archive.org/web/20110723023206/http://wouter.bbcmicro.net/pictures/computer/usa_bbc/index.html
 |archive-date=23 July 2011

}}</ref> with Econet and speech hardware as standard; the other for [[West Germany]].<ref name="whytehead-germanbbc">{{cite web
 |url=http://acorn.chriswhy.co.uk/Computers/BBCBDE.html
 |title=Chris's Acorns: German BBC Microcomputer Model B
 |access-date=28 March 2008
|last=Whytehead
 |first=Chris
 |date=9 November 2007
|url-status=dead
 |archive-url=https://web.archive.org/web/20100221035416/http://acorn.chriswhy.co.uk/Computers/BBCBDE.html
 |archive-date=21 February 2010

}}</ref> Despite concerns of unsuitability for the Australian market, with the design failing at temperatures above {{convert|35|C}},<ref name="furber20150325">{{Cite AV media |url=https://www.youtube.com/watch?v=y4WG549i3YY |archive-url=https://ghostarchive.org/varchive/youtube/20211221/y4WG549i3YY |archive-date=2021-12-21 |url-status=live |title=Building the BBC Micro (The Beeb) – Computerphile |date=25 March 2015 |type=YouTube |publisher=Computerphile |access-date=2020-06-20}}{{cbignore}}</ref> the machine was still "widely used in Australian schools".<ref name="museumsvictoria_396845">{{Cite web |title=Personal Computer – Acorn, BBC Proton, circa 1981 |url=https://collections.museumsvictoria.com.au/items/396845 |access-date=2023-02-20 |website=Museums Victoria Collections}}</ref> Export models were fitted with [[RF shielding|radio frequency shielding]] as required by the respective countries.

From June 1983, the name was always spelled out completely ("British Broadcasting Corporation Microcomputer System") to avoid confusion with [[Brown, Boveri & Cie]] in international markets.<ref name="micro-user-brown-boveri">{{cite magazine |date=June 1983 |title=Name changes for the worse |magazine=[[The Micro User]] |volume=1 |issue=4 |pages=112 |publisher=Database Publications |location=Stockport, UK |issn=0265-4040}}</ref> This came after warnings from the Swiss multinational not to market the computer with the BBC label in West Germany, effectively obliging Acorn to relabel "hundreds of machines" to comply with these demands.<ref name="pcn19830610_bbc">{{cite magazine |url=https://archive.org/details/Personal-Computer-News/PersonalComputerNews014-15Jun1983/page/n89/mode/1up |title=The Beeb boobs |magazine=Personal Computer News |date=10 June 1983 |access-date=15 October 2021 |pages=88 |volume=1 |number=14}}</ref>

US models include the BASIC III ROM chip, modified to accept the American spelling of <code>COLOR</code>, but the height of the graphics display was reduced to 200 [[scan line]]s to suit [[NTSC]] TVs,<ref name="bray-aug">{{cite book
 |last1=Bray |first1=Andrew C.
 |last2=Dickens |first2=Adrian C.
 |last3=Holmes |first3=Mark A.
 |year=1983
 |title=The Advanced User Guide for the BBC Microcomputer
 |url=http://www.nvg.org/bbc/doc/BBCAdvancedUserGuide-PDF.zip
 |format=zipped PDF
 |access-date=28 March 2008
|publisher=Cambridge Microcomputer Centre
 |location=Cambridge, UK
 |isbn=0-946827-00-1
 |pages=512
 |chapter=Appendix G
 |url-status=dead
 |archive-url=https://web.archive.org/web/20060114042612/http://www.nvg.org/bbc/doc/BBCAdvancedUserGuide-PDF.zip
 |archive-date=14 January 2006
}}</ref> severely affecting applications written for British computers. After the failed US marketing campaign, the unwanted machines were [[Remanufacturing|remanufactured]] for the British market and sold,<ref>{{cite web | url=http://8bs.com/see/iss1ad.jpg | title=US Issue 1 BBC | access-date=23 May 2011 | quote=These machines were originally manufactured for export to America. Having now shipped them back [...] | url-status=live | archive-url=https://archive.today/20130116053345/http://8bs.com/see/iss1ad.jpg | archive-date=16 January 2013 | df=dmy-all }}</ref><ref name="acornuser199205_softwarebargains">{{ cite magazine | url=https://archive.org/details/AcornUser118-May92/page/n54/mode/1up | title=Acorn BBC B Micro Computers | magazine=Acorn User | date=May 1992 | access-date=19 January 2024 | pages=53 }}</ref> resulting in a third export variant.<ref name="whytehead-exportbbc">{{cite web | url=http://chrisacorns.computinghistory.org.uk/Computers/BBCBUS.html | title=Chris's Acorns: US BBC Microcomputer (converted for UK) | access-date=19 January 2024 | last1=Whytehead | first1=Chris | df=dmy }}</ref>

==== Side product ====
In October 1984, the [[Acorn Business Computer]] (ABC)/Acorn Cambridge Workstation range of machines was announced, based primarily on BBC hardware.

=== Hardware features: successor models ===

==== B+64 and B+128 ====
In mid-1985, Acorn introduced the Model B+ which increased the total RAM to 64&nbsp;KB. This had a modest market impact and received a rather unsympathetic reception, with one reviewer's assessment being that the machine was "18 months too late" and that it "must be seen as a stop gap",<ref name="acornuser198507">{{cite magazine |url=https://archive.org/details/AcornUser036-Jul85/page/n161/mode/2up |title=B+ Grading |magazine=Acorn User |date=July 1985 |access-date=18 October 2020 |last1=Smith |first1=Bruce |pages=160–161}}</ref> and others criticising the elevated price of £500 (compared to the £400 of the original Model B) in the face of significantly cheaper competition providing as much or even twice as much memory.<ref name="yourcomputer198506">{{cite magazine |url=https://archive.org/details/YourComputer_198506/page/n20/mode/1up |title=D- for BBC B+ |magazine=Your Computer |date=June 1985 |access-date=28 November 2020 |pages=21}}</ref> The extra RAM in the Model B+ is assigned as two blocks, a block of 20&nbsp;KB dedicated solely for screen display (so-called [[Shadow RAM (Acorn)|shadow RAM]]) and a block of 12&nbsp;KB of special [[Sideways address space|sideways RAM]]. The B+128, introduced towards the end of 1985,<ref name="acornuser198311">{{cite magazine |url=https://archive.org/details/AcornUser040-Nov85/page/n8/mode/1up |title=Enter the 128k Beeb |magazine=Acorn User |date=November 1985 |access-date=18 October 2020 |pages=7}}</ref> comes with an additional 64&nbsp;KB (4 × 16&nbsp;KB sideways RAM banks) to give a total RAM of 128&nbsp;KB.

The B+ is incapable of operating some original BBC B programs and games, such as the very popular [[Castle Quest (1985 video game)|''Castle Quest'']]. A particular problem is the replacement of the [[Intel 8085#MCS-85 family|Intel 8271]] [[floppy-disk controller]]<ref>{{cite web |url=http://info-coach.fr/atari/documents/general/fd/I8271.pdf |title=8271/8271-6 Programmable Floppy Disk Controller |access-date=2012-11-03 |url-status=live |archive-url=https://web.archive.org/web/20130203081213/http://info-coach.fr/atari/documents/general/fd/I8271.pdf |archive-date=3 February 2013}}</ref> with the [[Western Digital FD1771|Western Digital 1770]]: not only was the new controller mapped to different addresses,<ref name="bplus-ug">{{cite book |title=BBC Microcomputer System User Guide |publisher=British Broadcasting Corporation |date=October 1984 |page=422 |url=http://regregex.bbcmicro.net/BPlusUserGuide-1.07.pdf |access-date=13 December 2011 |url-status=live |archive-url=https://web.archive.org/web/20120220005707/http://regregex.bbcmicro.net/BPlusUserGuide-1.07.pdf |archive-date=20 February 2012}}</ref> it is fundamentally incompatible, and the 8271 emulators that existed were necessarily imperfect for all but basic operation.<ref name="edwards86">{{cite magazine |first1=Kevin |last1=Edwards |date=January 1986 |title=Inside the 8271 – how your DFS really functions |magazine=[[The Micro User]] |volume=3 |issue=11 |pages=228 |publisher=Database Publications |location=Stockport, UK |issn=0265-4040}}</ref> Software that use [[copy protection]] techniques involving direct access to the controller do not operate on the new system.<ref name="acorn-appnote023">{{cite book |publisher=Acorn Computers |title=Support Group Application Note No. 023 |url=http://bbcdocs.com/filebase/library/appnotes/AppNote-023.pdf |archive-url=https://web.archive.org/web/20181020061135/http://bbcdocs.com/filebase/library/appnotes/AppNote-023.pdf |url-status=dead |archive-date=20 October 2018 |version=Issue 1 |date=9 July 1992 |access-date=12 December 2011}}</ref> Acorn attempted to alleviate this, starting with version 2.20 of the 1770 DFS, via an 8271-backward- compatible {{Key press|Ctrl}}+{{Key press|Z}}+{{Key press|Break}} option.<ref name="abcomputing198610_master">{{cite magazine |url=https://archive.org/details/AB_Computing_1986-10_OCR/page/n59/mode/2up |title=Master Your Master! |magazine=A&B Computing |last1=Grace |first1=Clive |date=October 1986 |access-date=19 March 2022 |pages=60–61}}</ref>

There is also a long-running problem late in the B/B+'s commercial life infamous amongst B+ owners, when Superior Software released ''[[Repton Infinity]],'' which did not run on the B+. A series of unsuccessful replacements were issued before one compatible with both was finally released.

==== BBC Master ====
{{Main|BBC Master}}
During 1986, Acorn followed up with the [[BBC Master]], which offers memory sizes from 128&nbsp;KB and many other improvements on the 1981 BBC Micro. It has essentially the same 6502-based BBC architecture but with many of the upgrades supported by the original design (extra ROM software, extra paged RAM, second processors) now included on the circuit board as internal plug-in modules.

=== Software ===
[[File:BBC Micro Elite screenshot.png|right|thumb|''[[Elite (video game)|Elite]]'' ([[Acornsoft]], 1984). The unusual game screen used two [[Computer display standard|display modes]] at once, to show both detail and colour.]]
The BBC Micro platform amassed a large software base of both games and educational programs for its two main uses as a home and educational computer. Notable examples of each include the original release of ''[[Elite (video game)|Elite]]''<ref>{{cite web |url=https://www.bbc.co.uk/blogs/technology/2008/03/remembering_the_bbc_micro_1.html |title=Remembering the BBC Micro |date=20 March 2008 |work=BBC News|access-date=30 November 2010 |url-status=live |archive-url=https://web.archive.org/web/20110403065728/http://www.bbc.co.uk/blogs/technology/2008/03/remembering_the_bbc_micro_1.html |archive-date=3 April 2011}}</ref> and ''[[Granny's Garden]]''. [[Programming language]]s and some applications were supplied on ROM chips to be installed on the motherboard. These load instantly and leave the RAM free for programs or documents.

Although appropriate content was little-supported by television broadcasters, [[telesoftware]] could be downloaded via the optional [[BBC Cheese Wedge|Teletext Adapter]] and the third-party teletext adaptors that emerged.

The built-in operating system, [[Acorn MOS]], provides an extensive [[API]] to interface with all standard peripherals, ROM-based software, and the screen.<ref>[[#bbcug|''The BBC Microcomputer User Guide'']], chapter 42, pp. 418–441.<br />The light pen, 1&nbsp;MHz bus and user port were supported by generic memory-mapped I/O calls (''OSBYTE'' 146–151), and Teletext graphics could be printed through ''OSWRCH'' like normal text. The Archimedes and its Interface Podule successfully emulated Teletext and the user port through these calls.</ref> Features specific to some versions of BASIC, like [[vector graphics]], [[Macro (computer science)|keyboard macros]], cursor-based editing, sound queues, and [[ADSR envelope|envelopes]], are in the MOS ROM and made available to any application. BBC BASIC itself, being in a separate ROM, can be replaced with another language.

BASIC, other languages, and utility ROM chips reside in any of four 16&nbsp;KB ''paged ROM'' sockets, with OS support for sixteen sockets via expansion hardware. The five (total) sockets are located partly obscured under the keyboard, with the leftmost socket hard-wired for the OS. The intended purpose for the perforated panel on the left of the keyboard was for a Serial ROM or Speech ROM. The paged ROM system is essentially modular. A language-independent system of ''star commands'', prefixed with an asterisk, provides the ability to select a language (for example <code>*BASIC</code>, <code>*PASCAL</code>), a filing system (<code>*TAPE</code>, <code>*DISC</code>), change settings (<code>*FX</code>, <code>*OPT</code>), or carry out ROM-supplied tasks (<code>*COPY</code>, <code>*BACKUP</code>) from the command line. The MOS recognises certain built-in commands, and polls the paged ROMs in descending order for service otherwise; if none of them claims the command, then the OS returns a <code>Bad command</code> error. Suitable ROM (or EPROM) images could be written and provide functions without requiring RAM for the code itself.
{{Main|Sideways address space}}

Not all ROMs offer star commands (ROMs containing data files, for instance), but any ROM can "[[Hooking|hook]]" into vectors to enhance the system's functionality. Often the ROM is a [[device driver]] for [[mass storage]] combined with a filing system, starting with Acorn's 1982 [[Disc Filing System]] (DFS) which API became the ''de facto'' standard for floppy-disc access. The Acorn Graphics Extension ROM (GXR) expands the VDU routines to draw geometric shapes, flood fills, and sprites. During 1985, [[Micro Power]] designed and marketed a Basic Extension ROM,<ref>{{Cite magazine |magazine=A & B Computing |date=February 1985 |title=Section – Language Extension |pages=27–29 |publisher=Argus Specialist Publications|location=London}}</ref> introducing statements such as <code>WHILE</code>, <code>ENDWHILE</code>, <code>CASE</code>, <code>WHEN</code>, <code>OTHERWISE</code>, <code>ENDCASE</code>, and direct mode commands including <code>VERIFY</code>.

Acorn strongly discouraged programmers from directly accessing the system variables and hardware, favouring official [[system call]]s.<ref name="bbc-userguide">{{cite book |title=The BBC Microcomputer User Guide |publisher=British Broadcasting Corporation |last=Coll |first=John |author-link=John Coll |year=1982 |location=London |pages=450, 468 |isbn=0-563-16558-8 |ref=bbcug}}</ref> This was ostensibly to make sure programs keep working when migrated to coprocessors that utilise the Tube interface, but it also makes BBC Micro software more portable across the Acorn range. Whereas untrappable [[PEEK and POKE|PEEKs and POKEs]] are used by other computers to reach the system elements,<ref>Sinclair Research Ltd,''ZX Spectrum BASIC programming'', chapters 23–25</ref> programs in either machine code or BBC BASIC instead pass parameters to an operating system routine. In this way, the 6502 can translate the request for the local machine or send it across the Tube interface, as direct access is impossible from the coprocessor. Published programs largely conform to the API except for games, which routinely engage with the hardware for greater speed, and require a particular Acorn model.

Many schools and universities employed the machines in [[Econet]] networks, and so networked multiplayer games were possible. Few became popular, due to the limited number of machines aggregated in one place. A relatively late but well documented example can be found in a dissertation based on a ringed [[RS-423]] interconnect.<ref>{{cite web |url=http://bishop.mc.duke.edu/bolo/guides/dissertation/ |title=An Experiment in Real-Time Networking |first=Stuart |last= Cheshire |date=19 May 1989 |archive-url=https://web.archive.org/web/20170318195804/http://bishop.mc.duke.edu/bolo/guides/dissertation/ |access-date=2017-10-20 |archive-date=2017-03-18}}</ref>

==== BBC BASIC built-in programming language ====
{{Main|BBC BASIC}}
[[File:Hard reset BBC Micro 32K Acorn DFS.gif|thumb|left|BASIC prompt after switch-on or hard reset]]
The built-in ROM-resident ''BBC BASIC'' programming language [[interpreter (computing)|interpreter]] realised the system's educational emphasis and was key to its success; it is the most comprehensive BASIC compared to other contemporary implementations, and runs very efficiently.<ref>{{cite magazine |magazine=Creative Computing |url=https://archive.org/details/creativecomputing-1984-03/page/n7 |page=6 |first=David |last=Ahl |date=March 1984 |title=Creative Computing Benchmark}}</ref> Advanced programs can be written without resorting to [[non-structured programming]] or machine code. Should one want or need to program in assembly language, BBC BASIC has a built-in assembler that allows a mix of BASIC and assembly language for the processor on which a particular implementation of BASIC is running.

When the BBC Micro was released, many competing home computers used [[Microsoft BASIC]], or variants typically designed to resemble it. Compared to Microsoft BASIC, BBC BASIC features IF...THEN...ELSE, REPEAT...UNTIL, and named procedures and functions, but retains [[GOTO]] and [[GOSUB]] for compatibility. It also supports high-resolution graphics, four-channel sound, pointer-based memory access (borrowed from [[BCPL]]), and rudimentary macro assembly. Long variable names are accepted and distinguished completely, not just by the first two characters.
{{Clear}}

==== Other languages ====
Acorn had made a point of not just supporting BBC Basic but also supporting a number of contemporary languages, some of which were supplied as ROM chips to fit the spare sideways ROM sockets on the motherboard. Other languages were supplied on tape or disk.

Programming languages from [[Acornsoft#Acornsoft Languages range|Acornsoft]] included:
* ISO [[Pascal (programming language)|Pascal]] (2× 16&nbsp;KB ROM + floppy disk)
* S-Pascal (disk or tape)
* [[BCPL]] (ROM plus further optional disk based modules)
* [[Forth (programming language)|Forth]] (16&nbsp;KB ROM)
* [[Lisp (programming language)|LISP]] (disk, tape, or ROM)
* [[Logo (programming language)|Logo]] (2× 16&nbsp;KB ROM)
* Turtle Graphics (disk or tape)
* Micro-[[Prolog]] (16&nbsp;KB ROM)
* [[COMAL]] (16&nbsp;KB ROM)
* [[C (programming language)|C]] (disk)

Many of these languages were also provided under the [[Panos (operating system)|Panos]] environment for the [[BBC Micro expansion unit#32016 Second Processor|32016 Second Processor]]. As the [[BBC Micro expansion unit#Z80 Second Processor|Z80 Second Processor]] provided a CP/M environment, languages available for CP/M were supportable via this route. For example, [[Turbo Pascal]] was regarded in one instance as "by far the best version of Pascal" for a BBC Micro with Z80 second processor.<ref name="beebug198503_pascal">{{cite magazine |url=https://acorn.huininga.nl/pub/magazines/Beebug/BeebUG%20Volume%2003%20Number%2009%20March%201985.pdf |title=Turbo Pascal |magazine=BEEBUG |date=March 1985 |access-date=23 September 2022 |last1=Maher |first1=John |pages=43–44 |volume=3 |issue=9}}</ref> DOS-based language implementations such as [[Borland Turbo C|Turbo C]] and Turbo Pascal could also be run by computers expanded with the Master 512 board,<ref name="acornuser198905_shibumi">{{cite magazine |url=https://archive.org/details/AcornUser082-May89/page/n130/mode/1up |title=DOS Solutions |magazine=Acorn User |date=May 1989 |access-date=4 May 2021 |last1=Futcher |first1=Dave |pages=129–130}}</ref> this being fitted to BBC Micro machines using a Universal Second Processor unit.<ref name="abcomputing198708">{{cite magazine |url=https://archive.org/details/AB_Computing_1987-08_OCR/page/n8/mode/1up |title=BBC to PC by Tube |magazine=A&B Computing |last1=Taylor |first1=Gordon |date=August 1987 |accessdate=8 November 2020 |pages=9–11}}</ref>

[[Torch Computers]]' Z80 expansions supported the [[UCSD Pascal|UCSD p-System]], and the Torch Unicorn expansion provided a Unix environment that featured a C compiler and other utilities, with Pascal and Fortran 77 implementations also advertised.<ref name="unicorn_tech">{{cite book |url=http://chrisacorns.computinghistory.org.uk/docs/Torch/Torch_UnicornTechOverview.pdf |title=Torch Unicorn Technical Overview |publisher=Torch Computers |accessdate=6 November 2020}}</ref>{{rp |pages=7}} Acornsoft also supplied a p-System product, developed by TDI, that required a [[BBC Micro expansion unit#6502 Second Processor|6502 Second Processor]] and at least one single-sided, 80-track disc drive.<ref name="microuser198510_pascal">{{ cite magazine | url=https://archive.org/details/micro-user-032/page/115/mode/1up | title=PASCAL on the p-SYSTEM | magazine=Micro User | last1=Malin | first1=Rowan | date=October 1985 | access-date=2 July 2024 | pages=115, 117 }}</ref> Acornsoft's p-System implementation corresponded to version IV.12 and also included a Fortran 77 compiler.<ref name="beebug198501_pascal">{{ cite magazine | url=https://archive.org/details/beebugv0308/page/7/mode/1up | title=Acornsoft's UCSD Pascal System | magazine=Beebug | last1=Maher | first1=John | date=January 1985 | access-date=2 July 2024 | pages=7–10 }}</ref>

Acornsoft C did not run on the original BBC Micro models, requiring the extra resources provided by the B+ and Master series machines. Beebug C did, however, run on the standard Model B and later machines. Both of these implementations provided compilers producing interpreted "p-code" as opposed to machine code, similar to Acornsoft's ISO Pascal and BCPL compilers. A [[Small-C]] implementation was also made available by Mijas.<ref name="acornuser198712_c">{{cite magazine |url=https://archive.org/details/AcornUser065-Dec87/page/n150/mode/1up |title=To C or not to C? |magazine=Acorn User |last1=Denning |first1=Adam |date=December 1987 |access-date=25 September 2022 |pages=149, 151, 153}}</ref>

For a BBC Micro without a second processor, Acornsoft's ISO Pascal primarily saw competition from Oxford Pascal. A Forth-based Pascal implementation from HCCS known as Pascal T was regarded as being "intended primarily for learning Pascal, rather than using it seriously",<ref name="acornuser198507_pascal">{{cite magazine |url=https://archive.org/details/AcornUser036-Jul85/page/n66/mode/1up |title=Pleasures of Pascal |magazine=Acorn User |last1=Williams |first1=Simon |date=July 1985 |access-date=2 October 2022 |pages=65, 67, 69–70}}</ref> putting it in the same category as Acornsoft's S-Pascal, described as "a simple subset of Pascal for teaching the language and structured programming".<ref name="electronuser198503_pascal">{{cite magazine |url=https://archive.org/details/ElectronUserVolume2/Electron-User-02-06/page/n10/mode/1up |title=Try S-Pascal and get rid of those spaghetti junctions |magazine=Electron User |date=March 1985 |access-date=4 September 2022 |last1=Waddilove |first1=Roland |pages=11–12}}</ref>

As a computer aimed at the education market, the BBC Micro was supported by several implementations of Logo: Acornsoft Logo competing with Logo products from Logotron, LSL, and the [[Open University]]. These products provided either one or two 16&nbsp;KB ROM chips for fitting inside the machine, although the Open University's Open Logo provided a second processor implementation that was loaded from disc. Acornsoft's Logo was itself written in the BCPL language whereas other implementations had been assembled to machine code. Compatibility with Logo dialects and standards varied, with Logotron Logo claiming a level of adherence to the broader [[LCSI|Logo Computer Systems Inc. (LCSI)]] industry standard, and the level of provided functionality differed between the BBC Micro implementations, with Acornsoft Logo providing the most comprehensive set of primitives in many areas. Support for various peripherals and accessories was advertised, [[Turtle (robot)|floor turtles]] having particular significance, but hardware extensions offering [[Sprite (computer graphics)|sprite]] capabilities were also developed for use with certain implementations, notably Logotron Logo.<ref name="acornuser198505_logo">{{cite magazine |url=https://archive.org/details/AcornUser034-May85/page/n66/mode/1up |title=Logo: The Big Four |magazine=Acorn User |last1=Telford |first1=Joe |date=May 1985 |access-date=4 April 2023 |pages=65, 67–70}}</ref> Logotron Logo was eventually judged to be the most popular product and was bundled with the Master Compact by Acorn.<ref name="acornuser198611_compact">{{cite magazine |url=https://archive.org/details/AcornUser052-Nov86/page/n102/mode/1up |title=Master Compact Great and Small |magazine=Acorn User |last1=Atherton |first1=David |date=November 1986 |access-date=4 April 2023 |pages=101–103}}</ref>{{rp |pages=103|quote=Logotron Logo was the most popular of the four versions released for the BBC micro, and Acorn has bundled this into the Compact instead of its own Logo.}}

=== Peripherals ===
[[File:BBC Micro analogue in (two joysticks).svg|thumb|Joystick circuit diagram]]
In line with its ethos of expandability, Acorn produced its own range of peripherals for the BBC Micro, including:
* Joysticks
* Tape recorder
* Floppy drive interface upgrade
* Floppy drives (single and double)
* Econet networking upgrade
* [[BBC Micro expansion unit#Econet bridge|Econet Bridge]]
* Winchester disk system
* [[BBC Micro expansion unit#6502 Second Processor|6502 Second Processor]]
* [[BBC Micro expansion unit#Z80 Second Processor|Z80 Second processor (with CP/M and business software suite)]]
* [[BBC Micro expansion unit#32016 Second Processor|32016 Second processor]]
* [[BBC Micro expansion unit#ARM Evaluation System|ARM Evaluation System]]
* [[BBC Micro expansion unit#Teletext adapter|Teletext adapter]]
* [[BBC Micro expansion unit#Prestel adapter|Prestel adapter]]
* Speech synthesiser
* Music 500 synthesiser<ref name="pcw198505">{{cite magazine |url=https://archive.org/details/PersonalComputerWorld1985-05/page/182/mode/2up |title=Acorn Music 500 |magazine=Personal Computer World |date=May 1985 |access-date=12 October 2020 |last1=Williams |first1=Noel |pages=182–184}}</ref>
* BBC [[Turtle (robot)]]
* BBC Buggy
* [[BBC Micro expansion unit#IEEE 488 interface|IEEE 488 Interface]]

Various products from other manufacturers competed directly with Acorn's expansions. For example, companies such as [[Torch Computers]] and Cambridge Microprocessor Systems offered second processor solutions for the BBC Micro.<ref name="practicalcomputing198412">{{cite magazine |last=Cullis |first=Roger |title=To the BBC by bus and Tube |url=http://chrisacorns.computinghistory.org.uk/docs/Mags/PC/PC_Dec84_2Proc.pdf |magazine=Practical Computing |date=December 1984 |access-date=19 October 2020}}</ref>

A large number of third-party suppliers also produced an abundance of add-on hardware, some of the most common being:
* RGB monitors
* Printers, plotters
* Modems

== Successor machines ==
{{Main|Acorn Archimedes}}
Acorn produced its own [[32-bit]] [[reduced instruction set computer|Reduced Instruction Set Computing]] (RISC) [[central processing unit|CPU]] during 1985, the ARM1. Furber composed a reference model of the processor on the BBC Micro with 808 lines of BASIC, and Arm Ltd. retains copies of the code for intellectual property purposes.<ref name="furber-acornworld-2009">{{cite AV media |url=http://www.computinghistory.org.uk/det/5633/Steve-Furber-Talk-Acorn-World-13-09-2009/ |title=Steve Furber Talk – Acorn World – 13-09-2009 |publisher=Centre for Computing History |date=22 September 2009 |people=Furber, Steve (speaker); Fitzpatrick, Jason (producer, director) |medium=Podcast |location=Haverhill, Suffolk, UK |time=25:35, 38:20 |quote=It turns out [the ARM reference model] is quite important because there are some interesting patent defence cases that depend to some significant extent on this information. [...] I wrote the BBC BASIC reference model, [...] and the complete thing is 808 lines of BBC BASIC, and that's the complete processor. |url-status=live |archive-url=https://web.archive.org/web/20111003114010/http://www.computinghistory.org.uk/det/5633/Steve-Furber-Talk-Acorn-World-13-09-2009/ |archive-date=3 October 2011}} The Acorn World exhibition was held in Huddersfield.</ref> The first prototype ARM platforms, the ARM Evaluation System and the A500 workstation, functioned as second processors attached to the BBC Micro's Tube interface. Acorn staff developed the A500's operating system ''in situ'' through the Tube until, one by one, the on-board I/O ports were enabled and the A500 ran as a stand-alone computer.<ref name="whytehead-a500">{{cite web |url=http://chrisacorns.computinghistory.org.uk/Computers/A500.html |title=Chris's Acorns: Acorn A500 (prototype) |work=Chris's Acorns |access-date=16 April 2025 |last=Whytehead |first=Chris }}</ref> With an upgraded processor, this was unveiled during 1987 in the form of the initial four models in the ''Archimedes'' series, three of which were eventually released,<ref name="introduction">{{cite tech report | url=http://chrisacorns.computinghistory.org.uk/docs/Acorn/Misc/AcornTraining_IntroToArc.pdf | title=Introduction to Archimedes | publisher=Acorn Computers Limited | access-date=28 February 2021 | pages=4 | quote=The particular models available were the A305 and A310, with 0.5 MB and 1&nbsp;MB of RAM respectively, and the A440, with 4&nbsp;MB of RAM.}}</ref> with the lower-specified two models (512&nbsp;KB and 1&nbsp;MB) exhibiting the BBC Microcomputer branding and bearing the distinctive red function keys. Although the Archimedes ultimately was not a major success, the ARM family of processors has become the dominant processor architecture in mobile embedded consumer devices, particularly mobile telephones.

Acorn's last BBC-related model, the BBC A3000, was released in 1989. It was essentially a 1&nbsp;MB Archimedes back in a single case [[Computer form factor|form factor]].

== Retro computing scene ==
[[File:BBC Micro creators with micro in 2012.jpg|thumb|left|upright|Clockwise from top left: Hermann Hauser, [[Andy Hopper]], [[Christopher Curry (businessman)|Christopher Curry]], [[Sophie Wilson]], David Allen, [[Chris Serle]], David Kitson, Chris Turner, and [[Steve Furber]] at the BBC Micro 30th anniversary in 2012]]

Furber said in 2015 that he was amazed that the BBC Micro "established this reputation for being reliable, because lots of it was finger-in-the-air engineering".{{r|furber20150325}} As of 2018, thanks to its ready expandability and I/O functions, there are still numbers of BBC Micros in use, and a [[retrocomputing]] community of dedicated users finding new tasks for the old hardware. They still survive in a few interactive displays in museums across the United Kingdom, and the [[Jodrell Bank]] observatory was reported using a BBC Micro to steer its 42&nbsp;ft radio telescope in 2004.<ref name="thereg-mypc">{{cite news |last=Libbenga |first=Jan |title=My PC is older than yours |work=Letters |publisher=The Register |date=19 January 2004 |url=https://www.theregister.co.uk/2004/01/19/my_pc_is_older_than/ |access-date=13 December 2011 |url-status=live |archive-url=https://web.archive.org/web/20120523170429/http://www.theregister.co.uk/2004/01/19/my_pc_is_older_than/ |archive-date=23 May 2012}}</ref> Furber said that although "the [engineering] margins on the Beeb were very, very small", when he asked BBC owners at a retrocomputing meeting what components had failed after 30 years, they said "you have to replace the [[capacitor]]s in the power supply but everything else still works".{{r|furber20150325}} The Archimedes came with 65Arthur, an [[emulator]] which ''[[Byte (magazine)|Byte]]'' stated "lets many programs for the BBC Micro run".<ref name="pountain198710">{{cite magazine |last=Pountain |first=Dick |date=October 1987 |url=https://archive.org/stream/byte-magazine-1987-10-rescan/1987_10_BYTE_12-11_Heuristic_Algorithms#page/n129/mode/2up |title=The Archimedes A310 |magazine=Byte |page=125 |access-date=4 August 2014}}</ref> Other emulators exist for many operating systems,<ref>{{cite web |url=http://www.nvg.ntnu.no/bbc/emul/ |title=nvg.ntnu.no |website=ntnu.no |access-date=8 May 2018 |url-status=dead |archive-url=https://web.archive.org/web/20070627010451/http://www.nvg.ntnu.no/bbc/emul/ |archive-date=27 June 2007}}</ref> including [[Beebdroid]] for Android and JS Beeb for the web.<ref>{{Cite web |last=<!-- Human name --> |first=<!-- Human name --> |date=1980–1989 |title=BBC Computer Literacy Project 1980–1989 |url=https://clp.bbcrewind.co.uk/ |access-date=2023-08-21 |website=BBC Computer Literacy Project |language=en}}</ref>

[[File:Hermann Hauser playing Blurp 2012.jpg|thumb|Acorn co-founder [[Hermann Hauser]] playing a game on a Master in 2012]]

In March 2008, the creators of the BBC Micro met at the [[Science Museum, London|Science Museum]] in London. There was to be an exhibition about the computer and its legacy during 2009.<ref name="bbc creators reunite" />

The UK [[National Museum of Computing]] at [[Bletchley Park]] uses BBC Micros as part of a scheme to educate school children about computer programming.<ref>{{cite news |last=Ward |first=Mark |title=Tech Know: BBC Micros used in retro programming class |work=BBC News |date=25 August 2010 |url=https://www.bbc.co.uk/news/technology-10951040 |access-date=25 August 2010 |archive-url= https://web.archive.org/web/20100826041939/http://www.bbc.co.uk/news/technology-10951040 |archive-date=26 August 2010 |url-status=live}}</ref>

In March 2012, the BBC and Acorn teams responsible for the BBC Micro and Computer Literacy Project met for a 30th anniversary party, entitled "Beeb@30". This was held at [[Arm Ltd.|Arm]]'s offices in Cambridge and was co-hosted by the [[Centre for Computing History]].<ref>{{cite web |url=http://www.computinghistory.org.uk/news/18405/30-Years-of-the-BBC-Micro-Celebration-Event-at-ARM/ |title=30 Years of the BBC Micro – Celebration Event at ARM – Computing History|website=www.computinghistory.org.uk|access-date=15 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20180415190420/http://www.computinghistory.org.uk/news/18405/30-Years-of-the-BBC-Micro-Celebration-Event-at-ARM/ |archive-date=15 April 2018}}</ref>

=== Continued development and support ===
Long after the "venerable old Beeb"<ref name="acornuser 1999xmas">{{cite magazine |url=http://audio22.archive.org/details/Acorn_User_Issue_215_1999_IDG_Media_GB_christmas_edition |title=Internet portal launched |magazine=Acorn User |date=December 1999 |access-date=16 August 2013 |issue=215 |pages=7 |url-status=live |archive-url=https://web.archive.org/web/20140414120931/http://audio22.archive.org/details/Acorn_User_Issue_215_1999_IDG_Media_GB_christmas_edition |archive-date=14 April 2014}}</ref> was superseded, additional hardware and software has been developed. Such developments have included Sprow's 1999 [[zip (file format)|zip]] [[data compression|compression]] utility and a [[read-only memory|ROM]] [[Y2K bugfix]] for the [[BBC Master]].<ref name="acornuser 1999xmas" />
{{Clear}}

There are also a number of websites still supporting both hardware and software development for the BBC Micros and Acorn in general.<ref>{{cite web |url=http://www.retrosoftware.co.uk/wiki/index.php/Main_Page |title=Retrosoftware|website=www.retrosoftware.co.uk|access-date=15 April 2018}}</ref><ref>{{cite web |url=http://stardot.org.uk/forums/ |title=stardot.org.uk – Index page |website=stardot.org.uk |access-date=15 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20170916054836/http://www.stardot.org.uk/forums/ |archive-date=16 September 2017}}</ref>

== Specifications ==
{| class="wikitable" style="text-align:center;"
! style="width:8em;" |
! style="width:22%;" | Model A
! style="width:22%;" | Model B
! style="width:22%;" | Model B+64
! style="width:22%;" | Model B+128
|-
| [[Central processing unit|Processor]]
| colspan="2" | [[MOS Technology 6502A]] @ 2&nbsp;[[megahertz|MHz]]
| colspan="2" | [[Rockwell Semiconductor]] 6512A @ 2&nbsp;MHz
|-
| [[Random-access memory|RAM]]
| 16&nbsp;KB
| 32&nbsp;KB
| 64&nbsp;KB composed of 32&nbsp;KB standard memory, 20&nbsp;KB video (''[[Shadow RAM (Acorn)|Shadow]]'') memory and 12&nbsp;KB extended (''special Sideways'') memory.
| 128&nbsp;KB composed of 32&nbsp;KB standard memory, 20&nbsp;KB video (''Shadow'') memory and 76&nbsp;KB extended (''Sideways'') memory.
|-
| [[Read-only memory|ROM]]
| colspan="2" | 32&nbsp;KB of ROM composed of a 16&nbsp;KB [[Acorn MOS|MOS]] (Machine Operating System) chip, and 16&nbsp;KB read-only paged space defaulting to the [[BBC BASIC programming language|BBC BASIC]] chip. Four paged 16&nbsp;KB ROM sockets standard, expandable to 16.
| colspan="2" | 48&nbsp;KB of ROM composed of 16&nbsp;KB MOS, 16&nbsp;KB [[Disk Filing System|DFS]], and 16&nbsp;KB read-only paged space defaulting to the BBC BASIC.
|-
| [[computer keyboard|Keyboard]]
| colspan="4" | Full-travel keyboard with a top row of ten red-orange [[function key]]s ƒ0–ƒ9. These generated [[text semigraphics]] when pressed with CTRL or SHIFT, and could be programmed with keyboard macros. The arrow keys and BREAK could also serve as function keys. Links on the keyboard PCB allowed users to select the behaviour of Shift+Break, and Display Mode on Power-up/Break. At least two slightly different keyboards were used during the life of the Model B; both had the same layout, but one had a slightly higher profile on each key.
|-
| Display
| As Model B except RGB (optional upgrade, soldering required).
| colspan="3" | 6-pin [[DIN connector|DIN]] digital RGB connector +5&nbsp;V/0&nbsp;V, 1&nbsp;V p-p composite colour or monochrome video (link S39) and built-in [[UHF]] ([[PAL]]) [[RF modulator]].
|-
| [[Graphics]]
| As Model B, but Modes 0, 1, 2, and 3 not available due to lack of memory.
| colspan="3" | Configurable graphics in Modes 0–6 (see table below) based on the [[Motorola 6845]] [[Video Display Controller|CRT controller]] or Mode 7, a special [[Teletext]] mode, based a [[Mullard]] [[Mullard SAA5050|SAA5050]] Teletext chip and only taking 1&nbsp;KB of RAM.
|-
| Sound
| colspan="4" | Four independent sound channels (one noise and three melodic) using the [[Texas Instruments]] [[Texas Instruments SN76489|SN76489]] [[sound chip]]. Phoneme-based speech synthesis using the Texas Instruments [[Texas Instruments LPC Speech Chips|TMS5220]] with a custom Acorn ROM (the "PHROM", a [[TMS6100]]) of [[Kenneth Kendall]]'s voice (optional).
|-
| [[magnetic tape data storage|Tape storage]]
| colspan="4" | [[Cassette tape#Data recording|Tape]] interface (with a relay operated motor control, controlled via 2 pins on a circular 7-pin [[DIN connector]]), using the CUTS [Computer Users' Tape Standard] variation of the [[Kansas City standard]] data encoding scheme operating at 1200 or 300 baud.
|-
| [[Disk storage]]
| colspan="2" | Optional [[floppy disk]] interface based initially on the Intel 8271 controller and later on the [[WD1770]], also requiring the installation of the [[Disc Filing System]] (DFS) ROM (and of soldered connector on Model A). ([[5.25-inch floppy disk|{{Fraction|5|1|4}}-inch]] floppy drive usually used) – Densities: Single-Sided, Single Density[SS/SD], Single-Sided, Double-Density[SS/DD], Double-Sided, Single-Density[DS/SD] and Double-Sided, Double-Density[DS/DD].
| colspan="2" | [[Floppy-disk controller]] based on the [[Western Digital]] [[WD1770]] controller and [[Disk Filing System|DFS]] ROM as standard (except ANB51, ANB52<ref name="chriswhy-models">{{Cite web |last=Whytehead |first=Chris |title=Chris's Acorns: BBC Microcomputers |url=http://acorn.chriswhy.co.uk/Computers/BBCMicros.html |access-date=30 November 2010 |url-status=live |archive-url=https://web.archive.org/web/20101125115416/http://acorn.chriswhy.co.uk/Computers/BBCMicros.html |archive-date=25 November 2010}}</ref><ref name="beebmaster-serials">{{Cite web |last=Wolstenholme |first=Ian |title=Beebmaster – Beebhelp – Acorn Serial Numbers |url=http://www.beebmaster.co.uk/BeebHelp/SerialNumbers.html |date=1 September 2010 |access-date=30 November 2010 |url-status=live |archive-url=https://web.archive.org/web/20110116142647/http://www.beebmaster.co.uk/BeebHelp/SerialNumbers.html |archive-date=16 January 2011}}</ref>).
|-
| [[Hard disk drive|Hard-disk storage]]
| None
| colspan="3" | Additional [[Advanced Disc Filing System|ADFS]] ROM required, external drive unit connected to the ''1&nbsp;MHz Bus'' interface.<ref>{{cite magazine |last=Burton |first=Robin |date=May 1993 |title=512 Forum |magazine=BEEBUG |volume=12 |issue=1 |pages=36–40}}</ref> (''Winchester'' Hard disc drives with 5&nbsp;MB, 10&nbsp;MB or 20&nbsp;MB capacities. Maximum of 512&nbsp;MB per drive, up to four drives).
|-
| Serial interface
| Optional upgrade, soldering required.
| colspan="3" | 5-pin 'domino'-[[DIN connector|DIN]] [[RS-423]] serial port.
|-
| Parallel interface
| Optional upgrade, soldering required.
| colspan="3" | 26-pin [[Insulation-displacement connector|IDC]] [[Centronics]]-compatible parallel port.
|-
| User port
| Optional upgrade, soldering required.
| colspan="3" | 20-pin IDC "user port" with 8 general purpose digital I/O pins and two special/trigger sensitive digital pins used for control purposes (for e.g. a ''turtle'' when using the [[Logo (programming language)|Logo]] programming language).
|-
| Analogue interface
| Optional upgrade, soldering required.
| colspan="3" | [[D-subminiature|DA15]] socket with four 8/12 bit analogue inputs based on μPD7002 IC (suitable for two [[joystick]]s), two inputs suitable for pushbuttons and an input for a [[light pen]].
|-
| 1&nbsp;MHz bus
| Optional upgrade, soldering required.
| colspan="3" | 34-pin IDC connector for generic expansion on a "daisy-chain" (used for connecting hard disks, sound synthesisers etc.).
|-
| The [[Tube (BBC Micro)|Tube]]
| Optional upgrade, soldering required.
| colspan="3" | 40-pin IDC connector for external second CPU. Options included a second [[MOS Technology 6502|6502]], a [[Zilog Z80]], the [[BBC Cheese Wedge#ARM Evaluation System|ARM Evaluation System]], or a [[National Semiconductor 32016]] (the latter was either branded "BBC Microcomputer System – 32016 Second Processor" or "Acorn Computer – Cambridge Co-Processor"), other vendors added 6809, 6800, 68000 and 68008. A 10&nbsp;MHz 80186 co-processor from a BBC Master can be connected through a co-processor adapter to a BBC Micro, thus enjoying a limited degree of PC compatibility.
|-
| [[Computer network|Network]]
| colspan="4" | Optional (standard on US model), [[Econet]] large-scale low-cost networking system @ 100&nbsp;kbit/s using the [[Motorola]] 68B54.
|-
| Secondary power output
| colspan="4" | Power supply for external disk drives, 6 pins:<br>0&nbsp;V, 0&nbsp;V, +5&nbsp;V&nbsp;DC&nbsp;@&nbsp;1.25&nbsp;A, +12&nbsp;V&nbsp;DC&nbsp;@&nbsp;1.25&nbsp;A, NC, 5&nbsp;V&nbsp;DC&nbsp;@&nbsp;75&nbsp;mA
|}

=== Display modes ===
Like the [[IBM Personal Computer|IBM PC]] with the contemporary [[Color Graphics Adapter]], the video output of the BBC Micro could be switched by software between a number of [[Computer display standard|display modes]]. These varied between 20 and 40-column text suitable for a domestic TV and 80-column text best viewed with a high-quality RGB-connected monitor; the latter mode was often too blurred to view when using a domestic TV via the UHF output. The variety of modes offered applications a flexible compromise between colour depth, resolution and memory economy. In the first models, the OS and applications were left with the RAM left over from the display mode.

Mode 7 was a [[Teletext]] mode, extremely economical on memory and an original requirement due to the BBC's own use of broadcast teletext (Ceefax). It also made the computer useful as a [[Prestel]] terminal. The teletext characters were generated using an [[Mullard SAA5050|SAA5050]] chip, for use with monitors and TV sets without a Teletext receiver. Mode 7 used only 1&nbsp;KB for video RAM by storing each character as its ASCII code, rather than its bitmap image as was needed for the other modes.

[[File:BBC Micro Ceefax (4752596631).jpg|thumb|Micro and Ceefax]]

Modes 0 to 6 could display colours from a logical palette of sixteen: the eight basic colours at the vertices of the [[RGB color model|RGB colour cube]] and eight flashing colours made by alternating the basic colour with its inverse. The palette could be freely reprogrammed without touching display memory. Modes 3 and 6 were special text-only modes that used less RAM by reducing the number of text rows and inserting blank scan lines below each row. Mode 6 was the smallest, allocating 8&nbsp;KB as video memory. Modes 0 to 6 could show [[diacritic]]s and other user defined characters. All modes except mode 7 supported [[bitmapped graphics]], but graphics commands such as DRAW and PLOT had no effect in the text-only modes.

The BBC B+ and the later Master provided 'shadow modes', where the 1–20&nbsp;KB frame buffer was stored in an alternative RAM bank, freeing the main memory for user programs. This feature was requested by setting bit 7 of the mode variable, i.e. by requesting modes 128–135.

{| class="wikitable"
!rowspan="2" |Graphics mode
!colspan="2" |Resolution (X×Y)
!rowspan="2" |Hardware<br />colours
!colspan="2" |Video RAM
!rowspan="2" |Type
|-
! style="text-align:center;" |Char cells
! style="text-align:center;" |Pixels
! style="text-align:center;" |used<br />(KB)
! style="text-align:center;" |map<br />(hexadecimal)
|-
| style="text-align:center;" |0
| style="text-align:center;" |80 × 32
| style="text-align:center;" |640 × 256
| style="text-align:right;" |2
| style="text-align:right;" |20
| style="text-align:center;" |{{mono|3000-7FFF}}
|Graphics
|-
| style="text-align:center;" |1
| style="text-align:center;" |40 × 32
| style="text-align:center;" |320 × 256
| style="text-align:right;" |4
| style="text-align:right;" |20
| style="text-align:center;" |{{mono|3000-7FFF}}
|Graphics
|-
| style="text-align:center;" |2
| style="text-align:center;" |20 × 32
| style="text-align:center;" |160 × 256
| style="text-align:right;" |8
| style="text-align:right;" |20
| style="text-align:center;" |{{mono|3000-7FFF}}
|Graphics
|-
| style="text-align:center;" |3
| style="text-align:center;" |80 × 25
| style="text-align:center;" |640 × 200
| style="text-align:right;" |2
| style="text-align:right;" |16
| style="text-align:center;" |{{mono|4000-7FFF}}
|Text
|-
| style="text-align:center;" |4
| style="text-align:center;" |40 × 32
| style="text-align:center;" |320 × 256
| style="text-align:right;" |2
| style="text-align:right;" |10
| style="text-align:center;" |{{mono|5800-7FFF}}
|Graphics
|-
| style="text-align:center;" |5
| style="text-align:center;" |20 × 32
| style="text-align:center;" |160 × 256
| style="text-align:right;" |4
| style="text-align:right;" |10
| style="text-align:center;" |{{mono|5800-7FFF}}
|Graphics
|-
| style="text-align:center;" |6
| style="text-align:center;" |40 × 25
| style="text-align:center;" |320 × 200
| style="text-align:right;" |2
| style="text-align:right;" |8
| style="text-align:center;" |{{mono|6000-7FFF}}
|Text
|-
| style="text-align:center;" |7 (Teletext)
| style="text-align:center;" |40 × 25
| style="text-align:center;" |480 × 500<ref>[http://www-uxsup.csx.cam.ac.uk/~bjh21/BBCdata/SAA5050.pdf Reference Data Sheet:SAA5050 Series] {{Webarchive |url=https://web.archive.org/web/20160303193433/http://www-uxsup.csx.cam.ac.uk/~bjh21/BBCdata/SAA5050.pdf |date=3 March 2016}}, ''Teletext Character Generator'', July 1982, Mullard.</ref>
| style="text-align:right;" |8
| style="text-align:right;" |1
| style="text-align:center;" |{{mono|7C00-7FFF}}
|Text
|}

=== Optional extras ===
A speech synthesis upgrade based on the Texas Instruments [[TMS5220]] featured sampled words spoken by BBC newscaster [[Kenneth Kendall]].<ref name="acornuser198210">{{cite magazine |url=https://archive.org/details/AcornUser003-Oct82/page/n30/mode/1up |title=The BBC Micro Speaks |magazine=Acorn User |date=October 1982 |access-date=30 October 2020 |pages=27–29}}</ref> This speech system was standard on the US model where it had an American vocabulary. The Computer Concepts Speech ROM also made use of the TMS5220 speech processor but not the speech ROMs, instead driving the speech processor directly.<ref name="acornuser198604">{{cite magazine |url=https://archive.org/details/AcornUser045-Apr86/page/n181/mode/2up |title=Technical Talk |magazine=Acorn User |last1=Phillips |first1=Martin |date=April 1986 |access-date=30 October 2020 |pages=180–181, 183}}</ref> The speech upgrade sold poorly and was largely superseded by [[Superior Software]]'s software-based synthesiser using the standard sound hardware.

The speech upgrade also added two empty sockets next to the keyboard, intended for 16&nbsp;KB serial ROM cartridges containing either extra speech phoneme data beyond that held in the speech paged ROM or general software accessed through the ROM Filing System. The original plan was that some games would be released on cartridges, but due to the limited sales of the speech upgrade combined with economic and other viability concerns,<ref name="acornuser198405">{{cite magazine |url=https://archive.org/details/AcornUser022-May84/page/n8/mode/1up |title=No cartridge boon for Beeb |magazine=Acorn User |date=May 1984 |access-date=29 September 2020 |pages=7}}</ref> little or no software was ever produced for these sockets. The cut-out space next to the keyboard (nicknamed the "ashtray") was more commonly used to install other upgrades, such as a ZIF socket for conventional paged ROMs.{{citation needed |date=August 2020}}

== Use in the entertainment industry ==
The [[BBC Domesday Project]], a pioneering multimedia experiment, was based on a modified version of the BBC Micro's successor, the [[BBC Master]].

Musician [[Vince Clarke]], of the British synth pop bands [[Depeche Mode]], [[Yazoo (band)|Yazoo]], and [[Erasure (duo)|Erasure]], used a BBC Micro (and later a [[BBC Master]]) with the UMI [[music sequencer]] to compose many hits.<ref name="Acorn User 1988-06">{{cite magazine |title=Erasure's Big Hit |magazine=Acorn User |date=1 June 1988}}</ref> In music videos from the 1980s featuring Vince Clarke, a BBC Micro is often present or provides text and graphics such as a clip for Erasure's "[[Oh l'amour]]". The musical group [[Queen (band)|Queen]] used the UMI Music Sequencer on their record ''[[A Kind of Magic]]''. The UMI is also mentioned in the CD booklet. Other bands who have used the BBC Micro for making music are [[A-ha]] and the reggae band [[Steel Pulse]]. Paul Ridout is credited as "UMI programmer" on [[The Cars|Cars]]' bassist/vocalist [[Benjamin Orr]]'s 1986 solo album, [[The Lace (Benjamin Orr album)|The Lace]]. Other UMI users included [[Blancmange (band)|Blancmange]], [[Alan Parsons]], and [[Robert John "Mutt" Lange|Mutt Lange]].<ref>{{cite magazine |title=UMI-2B |url=http://www.muzines.co.uk/articles/umi-2b/1197 |magazine=Sound On Sound |date=November 1985 |pages=24–32 |issn=0951-6816 |oclc=925234032}}</ref> [[Black Uhuru]] used the Envelope Generator from SYSTEM software (Sheffield) running on a BBC Micro, to create some of the electro-dub sounds on Try It ([[Anthem (Black Uhuru album)|Anthem]] album 1983).

The BBC Micro was used extensively to provide graphics and sound effects for many early 1980s BBC TV shows. These included, notably, series 3 and 4 of ''[[The Adventure Game]]'';<ref>{{cite web |url=https://www.youtube.com/watch?v=QX-cNDr9RLs |title=The Adventure Game S03E03, Part 3, Adam Tandy, Sandra Dickinson, Chris Serle – YouTube|website=[[YouTube]] |date=11 June 2010|access-date=2016-06-24 |url-status=live |archive-url=https://web.archive.org/web/20170325010422/https://www.youtube.com/watch?v=QX-cNDr9RLs |archive-date=25 March 2017}}</ref> the children's quiz game "First Class" (where the onscreen scoreboard was provided by a BBC Micro nicknamed "Eugene"); and numerous 1980s episodes of ''[[Doctor Who]]'' including "[[Castrovalva (Doctor Who)|Castrovalva]]", "[[The Five Doctors]]", and "[[The Twin Dilemma]]".

== Legacy ==
In 2013, NESTA released a [https://www.nesta.org.uk/report/the-legacy-of-bbc-micro/ report into the legacy of The BBC Micro], looking at the history and impact of the machine and The BBC Computer Literacy project. In June 2018, the BBC released its archives of the ''Computer Literacy Project''.<ref>{{Cite news |url=https://www.bbc.co.uk/news/technology-44628869 |title=BBC releases computer history archive |date=27 June 2018 |work=BBC News|access-date=2018-06-27|language=en-GB}}</ref><ref>{{Cite web |url=https://clp.bbcrewind.co.uk/ |title=BBC Computer Literacy Project Archive|website=clp.bbcrewind.co.uk|language=en|access-date=2024-01-29}}</ref>

The BBC Micro had a lasting technological impact on the education market by introducing an informal educational standard around the hardware and software technologies employed by the range, particularly the use of BBC BASIC, and by establishing a considerable investment by schools in software for the machine. Consequently, manufacturers of rival systems such as [[IBM PC compatible]]s (and almost-compatibles such as the [[RM Nimbus]]), the [[Apple Inc.|Apple]] [[Macintosh]], [[Commodore International|Commodore]] [[Amiga]], and Acorn as manufacturer of the BBC Micro's successor, the Archimedes, were compelled to provide a degree of compatibility with the large number of machines already deployed in schools.<ref name="acornuser198911_auntie">{{cite magazine |last=Futcher |first=Dave |date=November 1989 |url=https://archive.org/details/AcornUser088-Nov89/page/n129/mode/2up |title=Aping Auntie |magazine=Acorn User |access-date=7 May 2021 |pages=128–129, 131}}</ref>

== See also ==
{{Portal|BBC|1980s}}
* [[Acorn Electron]]
* [[Acorn Archimedes]]
* [[BBC Computer Literacy Project 2012]]
* [[BBC Master]]
* [[Raspberry Pi]]
* [[RiscPC]]
* [[Micro Bit]] – modern successor to the project
* TV
** ''[[Micro Men]]'' – BBC documentary drama
** ''[[Micro Live]]'' – BBC television programme
** ''[[Making the Most of the Micro]]'' – BBC television programme
* Magazines
** ''[[BEEBUG]]'' – user group magazine
** (BBC) ''[[Acorn User]]''
** ''[[The Micro User]]'' (also known as ''Acorn Computing'')
* [[NDR computer]]
* [[WDR computer]]

== References ==
{{Reflist}}

== External links ==
{{subject bar|auto=y|d=y|Technology}}
* [http://beebwiki.mdfs.net/ BeebWiki] – BBC Micro Wiki
* [https://web.archive.org/web/20140416090147/http://lowendmac.com/orchard/07/0228.html Acorn and the BBC Micro: From education to obscurity] (archived)
* [https://web.archive.org/web/20190322233256/http://www.computinghistory.org.uk/det/182/Acorn-BBC-Micro-Model-B/ The Acorn BBC Micro @ The Centre for Computing History]
* [http://www.bbcmicronews.co.uk/ BBC Micro connected to the Internet converting RSS headline feeds from the BBC News site into audio] {{Webarchive |url=https://web.archive.org/web/20201028014834/http://www.bbcmicronews.co.uk/ |date=28 October 2020}}
* [https://bbcmicro.co.uk/ BBC Micro Game Archive]
* [http://chrisacorns.computinghistory.org.uk/Computers.html#BBCMicro BBC Microcomputers]
* [http://vimeo.com/23537869 Video of a BBC computer show from 1985] via [[Vimeo]]
* [http://central.kaserver5.org/Kasoft/Typeset/BBC/Contents.html The BBC Microcomputer User Guide]
* [https://bbc.godbolt.org/ JavaScript based BBC Micro emulator] – [https://bbcmic.ro/ with sample programs to run]
<!-- * [http://www.nvg.ntnu.no/bbc/history.php3 History of the BBC Micro and related Acorn computers] – "The BBC Lives!" ''(NB: elderly page, several follow-on links dead)''-->

{{BBC Computer Literacy Project}}
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