The BBC Master 128 was released in January 1986, as a replacement for the highly successful BBC Micro range. It used the same basic architecture as the earlier system, and was backward compatible with it, but contained many enhancements and improvements. The BBC Master was based on the 8-bit 65C02 processor, a later revision of the 6502A used in the earlier Acorn systems, and was provided with four times the memory, 128 Kb. To allow existing peripherals to be used with the new system, it came with the same range of interfaces as the BBC Model B, including the Tube and the user port. Two cartridge slots, similar to those provided with the Plus 1, were also added to the system, as well as a numeric keypad. It could also be used with the Acorn Econet network system, and contained a space inside the case intended for an internal modem.
In addition to the hardware improvements, there were numerous software improvements. The operating system was enhanced, and additional software was provided in ROM, including an updated version of BBC BASIC (BBC BASIC IV) and Acorn's wordprocessor and spreadsheet, View and Viewsheet. The existing Disc Filing System (DFS), originally supplied with the BBC Model B, was supplemented by an updated version of the Advanced Disc Filing System (ADFS), originally supplied with the Electron's Plus 3, allowing better use to be made of 3.5" discs. (DFS was traditionally used with 5.25" discs.)
The BBC Master was released in a number of different varients. As well as the BBC Master 128, the Master Compact, Master ET, Master 512 and Master Turbo models were also released. The Master Compact (released in September 1986) was a standard BBC Master 128 fitted in to a three-box case along the same lines as the later Archimedes, with an integral 3.5" disc drive and lacking some of the interfaces (although an add-on was available which provided some of the missing interfaces). The Master ET was a Master 128 provided with an Econet interface, but without the disc drive and printer interfaces, and was intended as a network terminal. The Master 512 was a standard Master 128 with an internal 80186 coprocessor system, and 512 Kb of memory, running DOS. Finally, the Master Turbo was a BBC Master 128 with an internal 65C02 second procesor.
The basic BBC Master 128 sold for £499, and the Master Compact sold for £599. The BBC Master and its varients proved to be almost as popular as the original BBC Micro - by 1989 over 200,000 Master 128s and 70,000 Master Compacts had been sold.
In my opinion, one of the most interesting applications of the BBC Master was in connection with the BBC Domesday Project. The hardware, consisting of a specially enhanced BBC Master Turbo (the enhancement consisting of an internal SCSI interface and a Videodisc Filing System ROM) fitted with a laser disc player and trackerball, released in November 1986, was used to display facts about modern life in the U.K. Schools and members of the public all over Great Britain contributed to the project, by compiling information about their local area.
While Acorn was developing and marketing the BBC Master, the PC world was moving on from 8-bit processors to the 16-bit 80x86-class chips. Acorn had already realised that sooner or later the 6502 chip, and all 8- and 16-bit chips, would eventually become obsolete, and had already started developing their own 32-bit chip - the Acorn RISC Machine, or ARM.
Next: The start of the revival - The ARM and the Archimedes (1986 to 1988).
I currently have two of the Domesday laserdisc players without controlling BBC Masters and I'm looking to trade one of them for a controlling Master. If anyone can help, please get in touch with me via the contact link at the bottom of this page. Thanks.
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