BBC Micro

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One of the most durable of the 80s home computers, the BBC Micro was devised by Acorn Computers for the BBC, as a home computer. In the late 70s, there were internal discussions at the BBC about a computer-literacy project; the eventual decision was to produce a suitable computer to accompany a television series. Acorn Computers had been working on a successor to the Acorn Atom computer, which would have been named the Proton, and they eventually got the contract to produce the new computer, to be called the "BBC Microcomputer".

The machine was released in early 1982. The machine was wildly popular in the UK; as with Sinclair's ZX Spectrum, also released around that time, demand greatly exceeded supply and for some months there were long delays before customers received the machines they had ordered. A brief attempt to market the machine in the United States failed, due largely to the dominance of the Apple II. The success of the machine in the UK was largely due to its acceptance as an "educational" computer - the vast majority of UK schools used BBC micros to teach computer literacy and information technology skills.

The CPU was a 6502A 8-bit microprocessor that ran at 2MHz. A new version of BASIC, with a number of extensions to cover hardware features of the machine was allocated 32K of ROM. The machine had a typewriter-style keyboard, rather than the membrane or rubber keys found in many home machines of that time. Video output was to a television or via a RGB socket to a monitor. As was fairly standard at that time, programs were saved and loaded from cassette tapes.

The video display could be switched between 8 different video modes, with varying resolutions and numbers of colours available:

ModeResolutionTextColoursMemory used
0640 by 25680 by 32220K
1320 by 25640 by 32420K
2160 by 25620 by 321620K
3 - 80 by 25216K
4320 by 25640 by 32210K
5160 by 25620 by 32410K
6 - 40 by 2528K
7teletext40 by 2516 1K

The "Beeb", as it soon became known by its users, initally came in two models; the Model A at 235 UK pounds, and the Model B at 335 UK pounds. The Model A had 16K of user RAM; the Model B had 32 K of user RAM, and included a number of extra I/O interfaces: A Serial and parallel printer port, and 8-bit I/O port, four analogue inputs and an expansion connector that enabled other hardware to be connected. There was also an interface called the Tube, that allowed a second processor to be added (This was soon used in third-party add-ons, including a Zilog Z80 board and disk drive that allowed the BBC machine to run CP/M programs.)

Large numbers of games were written including the first version of the classic Elite, and a wide range of add-ons and expansions were available, as the machine had provision for floppy disk drives and networking hardware to be added; there were also sockets for the addition of extra ROM to the system.

Even today, (October 2001) thanks to its ready expandability and I/O functions, there are still numbers of BBCs in use, and a community of dedicated users finding new things to do with the old hardware.

A cut-down version of the BBC Micro, intended more for game playing was the Acorn Electron; games were wriiten specially for the Electron's more limited hardware, but they could also be run on the BBC.