Acorn BBC Micro Model A

The Acorn BBC Micro Model A was the lower-cost entry model created for the BBC Computer Literacy Project. Its 16KB RAM and omitted interface circuitry reduced the price, while retaining the 2 MHz 6502 and BBC BASIC environment.

Most Model A machines were later upgraded toward Model B specification, making unmodified examples comparatively uncommon.

Notable Features

• MOS Technology 6502A at 2 MHz forms the centre of the system.
• The standard memory and storage configuration was 16KB RAM and Cassette interface; optional floppy upgrade.
• Its principal display arrangement was Television or composite video monitor.

Historical Significance

• Most Model A machines were later upgraded toward Model B specification, making unmodified examples comparatively uncommon.
• This page represents a distinct Acorn model rather than a regional, memory-only or bundled-software variation.

Collector’s Notes

• Original keyboards, power supplies, manuals, expansion cards and storage hardware materially improve a surviving system.
• Internal revisions and dealer-installed upgrades mean an individual machine should be checked against its serial label and fitted hardware.

Specifications

Technical Information
Name	Acorn BBC Micro Model A
Manufacturer	Acorn Computers
Launched	Tuesday, December 1, 1981
Discontinued	1983
Launch Price	£235
Country	United Kingdom
CPU	MOS Technology 6502A at 2 MHz
Units Sold
Operating System	BBC Micro MOS with BBC BASIC
I/O	UHF, composite, cassette and expansion sockets; many Model B interfaces omitted
Keyboard	Integrated 74-key keyboard with ten function keys
Storage	Cassette interface; optional floppy upgrade
Sound	Texas Instruments SN76489; three tone channels plus noise
Graphics	Reduced set of BBC display modes because only 16KB RAM was fitted
Display	Television or composite video monitor
ROM	32KB MOS and BBC BASIC ROM; sideways ROM expansion
RAM	16KB RAM
CPU Speed	2 MHz