Acorn BBC Micro
In 1980, the BBC was grappling with questions about the United Kingdom's digital future. Officials at the British public broadcaster watched with concern as American companies dominated the microcomputer market. Available machines either cost a fortune or offered laughably limited capabilities. Faced with this situation, the BBC decided to take matters into its own hands and launched an ambitious project: to create a personal computer that would accompany its educational programming.
The specifications established by the BBC reflected this educational ambition. The machine would need to incorporate the BASIC language, feature a proper keyboard worthy of the name, display color graphics, and accept extensions such as teletext. Above all, its price would need to remain within reach of schools and motivated individuals. A considerable technical and commercial challenge.
The tender issued in late 1980 attracted several candidates. Among them was Acorn Computers, a small Cambridge company working on a prototype called Proton. This machine impressed the BBC evaluators, who favored it over the Sinclair ZX-81, still in gestation. Acorn won the contract and officially renamed its prototype the "BBC Microcomputer".
The collaboration between Acorn's engineers and the BBC's teams proved fruitful. The initial prototype underwent numerous improvements that far exceeded the original specifications. ICL and Cleartone handled manufacturing. The architecture was based on the 6502A processor clocked at 2 MHz, a reliable and proven chip. Two specialized integrated circuits completed the package: one handled graphics, the other serial interfaces.
Two versions were released simultaneously in early 1982. Model A sold for £235 with 16 KB of RAM, while Model B cost £335 for 32 KB. The latter featured more connectivity: serial and parallel interfaces, an 8-bit user port, analog inputs, and an expansion bus. One technical innovation deserves mention: the "Tube" interface, which allowed connection of a second processor.
The integrated BASIC was surprisingly rich. Similar in philosophy to Microsoft BASIC, it distinguished itself through numerous specific extensions. The operating system and BASIC occupied 32 KB of ROM, a generous allocation. The professional keyboard featured 64 keys arranged in the QWERTY standard, complemented by 10 programmable function keys.
Graphics performance constituted a major asset. Eight different modes allowed mixing of text and high-resolution graphics as needed. Mode 7, teletext-compatible, produced color graphics while consuming only one kilobyte of memory. A sound chip generated three simultaneous notes and various effects, with sophisticated software control of sound envelopes.
Extensibility set the BBC Micro apart from its competitors. Interfaces for floppy disk drives and Econet networking were integrated directly on the motherboard. A speech synthesis option, developed with Richard Baker, the BBC's star presenter, could pronounce approximately 150 pre-programmed words. Prestel and teletext adapters, planned for spring 1982, opened the way for program downloads.
The expansion possibilities appealed to advanced users. A second 6502 processor, a Z-80 for running CP/M, or a 16-bit National 16032 processor capable of addressing 16 MB of memory could be connected via the Tube interface. Dedicated monitors completed the range: a monochrome model at £105 and a color model at £288.
The BBC commissioned professional applications: word processor, spreadsheet, domestic database, computer-aided design. Third-party publishers developed educational and entertainment software. A comprehensive user manual accompanied each machine, along with a cassette of 16 demonstration programs.
A few flaws marred the picture. The plastic case lacked durability. The 32 KB of user memory sometimes proved insufficient, with the operating system consuming up to 8 KB. In high-resolution graphics mode, only 2 KB remained available. Teletext mode sometimes displayed erroneous characters due to its specific character set. No cassette cable was supplied with the machine.
These minor defects did not detract from the product's overall excellence. Display quality was impressive: 80 characters per line remained perfectly legible on a standard black-and-white television thanks to a specially designed font. Teletext mode offered one of the best visual renderings of its generation.
The BBC Micro surpassed most Japanese and American productions of the era through its technical richness and modularity. Commercial success followed: 100,000 units were planned for the first year. This achievement resulted from the meeting of Acorn's technical expertise and the BBC's educational vision.
The machine became the standard educational tool in British schools during the 1980s. It introduced an entire generation to computing and fostered a national digital culture. The experience Acorn gained in processor design would later lead to the ARM architecture, present in virtually all modern mobile devices on the planet.