--- title: Acorn Computer Archimedes A4000 categories: - Computers types: - Professional Computer origins: - United Kingdom years: - '1992' cpus: - ARM 250 32 bit RISC params: name: Archimedes A4000 image: /media/museum/photos/acorn_a4000_running_s1.jpg company: /companies/acorn-computer company_name: Acorn Computer specs: - label: NAME value: Archimedes A4000 - label: MANUFACTURER value: Acorn Computer - label: TYPE value: Professional Computer - label: ORIGIN value: United Kingdom - label: YEAR value: september 1992 - label: BUILT IN LANGUAGE value: BBC BASIC - label: KEYBOARD value: Full-stroke PC 102 keys style - label: CPU value: ARM 250 32 bit RISC - label: SPEED value: 12 MHz - label: CO-PROCESSOR value: MEMC (memory), VIDC (Video and Sound), IOC (I/O) - label: RAM value: 2 to 4 MB - label: ROM value: 2 MB - label: TEXT MODES value: Up to 132 columns x 32 rows - label: GRAPHIC MODES value: VGA video output. Several graphic modes. Among them 640 x 256 or 512 pixels - label: COLORS value: Palette of 4096 colours - label: SOUND value: 8 voices synthesizer - label: I/O PORTS value: Centronics, RS423, VGA, 1 expansion slot (same as A3000, A3010 and A3020) - label: BUILT IN MEDIA value: One 3.5'' FDD, 0 to 210 MB HDD - label: OS value: RISC OS 3.11 - label: POWER SUPPLY value: Built-in power supply unit - label: PRICE value: Approx. £800 tabs: - photos - hardware - emulators - links - docs forum_thread: 692 photos: - title: LARGE VIEW subtitle: '' text: '' image: /media/museum/photos/acorn_a4000_running_s2.jpg - title: 'MAIN UNIT #1' subtitle: '' text: '' image: /media/museum/photos/acorn_a4000_system_s2.jpg - title: 'MAIN UNIT #2' subtitle: '' text: '' image: /media/museum/photos/acorn_a4000_system_s3.jpg - title: 'MAIN UNIT #3' subtitle: '' text: '' image: /media/museum/photos/acorn_a4000_frontview_s1.jpg - title: CASE subtitle: '' text: The A4000 case was a slim down version of the A5000's image: /media/museum/photos/acorn_a4000_a5000case_s1.jpg - title: REAR PANEL subtitle: '' text: |- From left to right: • AC Power in/out sockets\ • Keyboard mini din connector\ • Parallel printer DB25 connector\ • Serial RS232 DB9 connector\ • Optional Econet DB15 connector\ • Stereo sound output jack\ • Standard DB15 video output\ • The Midi card provides Midi Thru, Midi in, Midi out and User port connectors. image: /media/museum/photos/acorn_a4000_rearcon_s1.jpg - title: OPENED subtitle: '' text: Note the clipped hard disk and floppy disk drive and the Midi expansion card. image: /media/museum/photos/acorn_a4000_opened_s1.jpg - title: MOTHERBOARD subtitle: '' text: |- **(1)** ARM 250 CPU\ **(2)** Expansion connectors\ **(3)** RISC OS 3.11 ROMs\ **(4)** Video and I/O custom chipset\ **(5)** 4 MB RAM chips (2 MB standard + 2 MB in DIP ICs)\ **(6)** FDD and HDD connectors. image: /media/museum/photos/acorn_a4000_mainboard_s1.jpg hardware: - title: 486 CARD subtitle: '' text: Allowed Archimedes series computers to run 32-bit PC-DOS software. It was delivered with a manual, a driver disk and PC-DOS 6.3 image: /media/museum/hardware/acorn_a39000_486card_1.jpg - title: GRAPHICS ACCELERATOR subtitle: '' text: |- Graphics accelerator card (called "ColourCard") for A3000, Archimedes and A5000.\ Company : Computer Concepts\ Enhanced potential for Archimedes series including 15-bit desktop modes (i.e. 800\*600 @ 256 colours). Thanks to **Chris Syntichakis** image: /media/museum/hardware/acorn_a5000_colorcard_1.jpg - title: CUMANA SCSI CARD subtitle: '' text: |- 16-bit SCSI-1 card\ Company: Cumana.\ There are an external port for scanners/CD-ROM etc. and 2 internal ports for SCSI and Floptical drives. Thanks to **Chris Syntichakis** image: /media/museum/hardware/acorn_a5000_scsicard_1.jpg - title: SERIAL CARD subtitle: '' text: |- From Atomwide's site:\ High speed serial card featuring three ports, each in the shape of a standard 9-pin ‘D’ plug. Each port on the card is capable of running at up to 460,800 bits per second, and employs a 16-byte FIFO buffer to reduce loading on the host computer’s processor, so improving communications reliability. All serial cards are standard single-width podules, and are fully compatible with Atomwide 6 and 8-slot RiscPC backplanes. image: /media/museum/hardware/acorn_a5000_serialcard_1.jpg - title: MIDI CARD subtitle: '' text: Allowed Archimedes systems to interact with any midi sound device. image: /media/museum/hardware/acorn_a4000_midicard_s1.jpg emulators: - title: Arculator url: http://b-em.bbcmicro.com/arculator/ platform: Windows text: An excellent Windows-based Archimedes emulator, plays many games and has simple usage. - title: Red Squirrel url: http://www.red-squirrel.org/ platform: Windows text: An Emulator of Arm based Acorn machines for Windows 98/ME/2000/XP - title: Virtual Acorn url: http://www.virtualacorn.co.uk/ platform: Windows text: Excellent but commercial software - £30 - title: ARCHIE url: http://www.geocities.com/siliconvalley/campus/5427/ platform: Multiplatform text: Archie is an emulation of the Acorn Archimedes hardware (A3xx/A4xx/A3xxx) for DOS/Windows links: - title: Web Wiz CAPTCHA url: http://www.webwizcaptcha.com text: '' docs: - title: TOM'S ARCHIMEDES DOCS (INTERNAL HARDWARE) url: http://b-em.bbcmicro.com/arculator/index.html cover: /media/museum/docs/couvs/vide.gif text: |- [**TOM'S ARCHIMEDES DOCS (INTERNAL HARDWARE)**](http://b-em.bbcmicro.com/arculator/index.html)written by Tom Mowalker  compiled/archived by Tom Mowalker\  type of document : HTML\  source : [Arculator](http://b-em.bbcmicro.com/arculator/index.html) related: - /museum/acorn-computer-a4 - /museum/acorn-computer-archimedes - /museum/acorn-computer-archimedes-a3000 - /museum/acorn-computer-archimedes-a3010 - /museum/acorn-computer-archimedes-a3020 - /museum/acorn-computer-archimedes-a5000 - /museum/acorn-computer-archimedes-a7000 oc_id: 709 source: url: https://web.archive.org/web/20230202014543/http://www.old-computers.com/museum/computer.asp?c=709 date: '2023-02-02' --- The Acorn A4000 was a slightly cheaper cut down [A5000](/museum/acorn-computer-archimedes-a5000/), with a shorter case, one expansion slot and an ARM250 processor. Curiously, the machine had its floppy and hard drive fixed to the chassis with a wire clip which meant these could be quickly replaced without tools, whereas replacing the hard disk on the A5000 was a more fiddly operation requiring the expansion slot plane and the whole chassis holding the drives to be removed. Many of the features (ARM250, VGA screen modes, RISC OS 3) of this model were implemented into the lower end A3010 and A3020 computers. The keyboard was a much cheaper type more similar to a generic PC unit. A rare 486 PC emulator on a card was available, similar cards became popular on the later RISC PC models. Information supplied by **Jonathan Hayward**