Lessons from Discarded Computer Architectures - History of Computing: Learning from the Past - page 198

Lessons from Discarded Computer Architectures
Andrew E. Fluck
University of Tasmania
Locked Bag 1307, Launceston, Tasmania, 7250, Australia
[e-mail]
Abstract. The BBC microcomputer was one of several nationally produced
which were superseded by the International Business Machines (IBM) Personal
Computer (PC). This reflected the results of both an international market com-
petition and rivalry between different US processor manufacturers. Along with
the hardware, valuable software and supporting educational ideologies were
discarded. As we make choices about technological innovation, to what degree
are we selecting potential efficacy or responding to marketing hype?
Keywords: BBC microcomputer, IBM Personal Computer, Apple II, computer
hardware, operating systems.
1 Introduction
The BBC microcomputer was an 8-bit machine based on the Motorola 6502 proces-
sor. It made a huge impact in British schools, putting predecessors into the shade of
its colour graphics. Its successor, the Archimedes was almost as successful, but ran
into the juggernaut of the IBM PC - and the rest is history. Almost.
2 The BBC Microcomputer - A Withered Branch
In 1979-80 the British Broadcasting Company (BBC) started the BBC Computer Lit-
eracy Project and put out a tender for a microcomputer to accompany the television
series The Computer Programme. Acorn was a firm started by two former Sinclair
employees, marketing director Chris Curry and researcher Hermann Hauser. Their
firm won the tender in April 1981 and released the BBC Microcomputer later that
year. The large keyboard unit connected to a conventional television, which became
the screen for the computer. Based on the 8-bit Motorola 6502 processor, the initial
model had 16k bytes of RAM, and cost GBP 299. Backup storage was initially to cas-
sette tape, with floppy disks (5¼”) coming later. Notably the computer had many in-
terfaces, including networking (CDMA econet), a serial RS-423 port, analog input
(for joysticks etc.), parallel input/output user port Centronix printer port, RGB, com-
posite video and TV outputs. The operating system was in read-only memory (ROM),
and this contained a BASIC interpreter. Additional language ROMS could be in-
stalled to give extra functionality. One such language was Micro PROLOG which was