Launched in 1981 to coincide with a computer literacy drive by the BBC, the Model A was the cheaper of Acorn's two machines at £299. The machine's high cost was compensated for by very impressive expansion possibilities including disc drives, a second processor and network capabilities (Econet).
The Acorn BBC model A was the successor of the Acorn Atom was originally known called the Acorn Proton. It was a very popular computer in the UK and was widely used in schools, but it didn't have great success elsewhere (even though it did have great features, it was too expensive).
This computer got its name because in 1980, the BBC decided to start a computer literacy television series. The network realized that, with more powerful and increasingly inexpensive microcomputers, it would soon be possible to create them with enough computing power to offer their owners personal hands-on experience with microcomputers at an affordable price.
The BBC considered the NewBrain computer and rejected it. Acorn and Sinclair Research, along with other companies, then submitted designs, and Acorn won. The BBC Micro was then used almost universally in British schools from its birth into the 90's.
It was followed in 1982 by the Acorn BBC model B. The Model B had the same features but had 32 KB RAM (expandable to 64K). One of its most popular peripherals was the "Torch" floppy disk unit, a 5.25" floppy disk drive with a Z80 which allowed the BBC to use CP/M software. Acorn also made a cheaper version of the BBC (fewer connectors & video modes) called Acorn Electron.
In March 1981 we knew the BBC were interested in Acorn. Hermann Hauser told us that the BBC were coming five days before they arrived but we didn't even have a machine.
There was a huge gap between what the BBC wanted and what we had planned to build. Their technical specification was basically a Z80 (processor) machine running CP/M (an operating sytem). What they contracted from Acorn was a 6502 (processor) machine running a proprietary operating system.
The other legacy which keeps coming back to me is that a generation of people cut their computing teeth on the BBC Micro so I still meet people who say they did their first computing on the Beeb.
One very interesting complaint that I have from lots of computer science departments now is that people don't learn how to programme at school anymore. When they use PCs they don't programme them. When they used BBC Micro they programmed them themselves because it was so simple to write in BBC Basic.
It's hard to say if we would have specified a computer similar to the BBC Micro if we had not been approached by the BBC.
In the BBC Model B+ the Intel 8271 Disc Controller was replaced by a Western Digital WD1770. Acorn also produced and 1770 Disc Interface Upgrade kit to upgrade BBC Micros. With the 1770 Disc interface fitted, the BBC Micro could be upgraded with the Advanced Disc Filing System ROM (see also Winchester Disc System).