Acorn System 4

The Acorn System 4 was a higher-capacity professional version of the modular 6502 computer, normally equipped with more memory and floppy storage than the System 3. Its card cage could be tailored for laboratory, education and business use.

It demonstrated Acorn’s move from kit computers toward complete professional systems while retaining the adaptable Eurocard bus.

Notable Features

• MOS Technology 6502 at 1 MHz forms the centre of the system.
• The standard memory and storage configuration was Typically 32KB; configurable through Eurocard memory boards and One or two 5.25-inch floppy drives.
• Its principal display arrangement was External monitor.

Historical Significance

• It demonstrated Acorn’s move from kit computers toward complete professional systems while retaining the adaptable Eurocard bus.
• 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 System 4
Manufacturer	Acorn Computers
Launched	Tuesday, January 1, 1980
Launch Price	£1525
Country	United Kingdom
CPU	MOS Technology 6502 at 1 MHz
Units Sold
Operating System	Acorn DOS and BASIC
I/O	Eurocard expansion, floppy, video, printer, serial and user I/O according to configuration
Keyboard	Integrated full-size keyboard
Storage	One or two 5.25-inch floppy drives
Sound	Optional sound through expansion hardware
Graphics	Text and graphics through the fitted Acorn video card
Display	External monitor
ROM	Monitor, BASIC and Acorn DOS ROMs
RAM	Typically 32KB; configurable through Eurocard memory boards
CPU Speed	1 MHz