Acorn Archimedes
From Free net encyclopedia
Plugwash (Talk | contribs)
/* A new range and a laptop */
Next diff →
Current revision
The Acorn Archimedes was Acorn Computers Ltd's first general purpose home computer based on their own 32-bit ARM RISC CPU, and spawned a family of very capable machines with various options.
Contents |
Description; Early models
The first models were released in June 1987, as the 300 and 400 series. The machines differed primarily in that the 400 series included more expansion slots (four instead of two) and a ST506 controller for an internal hard drive. Both models included the Arthur OS (later versions to be called RISC OS, see below), BBC BASIC and an emulator for Acorn's earlier BBC Micro, and were mounted in two-part cases with a small central unit, monitor on top, and a separate keyboard and three-button mouse. All models featured onboard 8 channel stereo sound and were capable of 256 colour screenmodes.
Four models were initially released with different amounts of memory, the A305, A310, A410 and A440. The 300 and 400 were followed by a number of machines with minor changes and upgrades:
- (A500 - 4 MB RAM, Archimedes development machine, never sold [1])
- A305 - 512 KB RAM
- A310 - 1 MB RAM
- A410 - 1 MB RAM
- A420 - 2 MB RAM, 20 MB hard disk
- A440 - 4 MB RAM, 40 MB hard disk
- (A4xx/1 editions with improved memory controller)
- A540 - 4 MB RAM, ARM 3 processor, 100 MB hard Disk
- (A680 and M4 - 8 MB RAM, RISC iX development machines, never sold)
- R140 - 4 MB RAM, 52 MB hard disk, RISC iX UNIX workstation
- R260 - 8 MB RAM, ARM 3 processor, 100 MB hard disk, RISC iX UNIX workstation
- R225 - 4 MB RAM, ARM 3 processor, RISC iX UNIX network computer
The A3000 and A5000
Work began on a successor to the Arthur OS, initially named Arthur 2, but with the release of the Hollywood movie of the same name it was renamed to RISC OS 2. Along with it, a number of new machines were introduced as well, and in May 1989 the 300 series was phased out in favor of the new Acorn A3000. The earlier models were capable of being upgraded to RISC OS 2 by replacing the ROM chips which contained the Operating System.
Unlike the previous Archimedes models, the A3000 came in a single-part case similar to the Amiga 500 and Atari ST computers, with the keyboard attached to the main unit. This kind of housing consumes a lot of desktop space, a problem that Acorn tried to overcome by offering a monitor stand that could be attached to the base unit. The new model only sported a single expansion slot. Unlike the 300 series, the 400 series was kept in production.
The other new model, the A5000, came in a newly designed two-part case that looked more conventional than the housings of its predecessors. It featured the new 25 MHz ARM3 processor, while the A3000 was still equipped with an 8 MHz ARM2. The A3000 ran RISC OS 2, while the A5000 ran the new RISC OS 3.0. It came with 2 or 4 MB of RAM, compared to the A3000's 1 MB, and featured either a 40 MB or an 80 MB hard drive. Its video capabilities were enhanced as well and the A5000 could comfortably display VGA resolutions of up to 800 × 600 pixels. It was the first Archimedes to feature a High Density capable floppy disc drive as standard and could read and write various formats, including DOS and Atari discs. A later version of the A5000 was available, featuring a 33 MHz ARM3, 4 or 8 MB of RAM, an 80 or 120 MB hard drive and a revised OS, namely RISC OS 3.10.
As previously, earlier machines were capable of being upgraded to the new RISC OS 3, as well as the ARM3 CPU. Via a third party upgrade, earlier models could benefit from equal video performance to the A5000.
A new range and a laptop
In 1992, a new range was produced, using the ARM250 microcontroller, an ARM2 processor with integrated memory and video controllers, performing better thanks to an increase in clock frequency, and running RISC OS 3.10. The A30x0 series had a one-piece design, similar to the A3000 but far smaller, while the A4000 looked like a slightly slimmer A5000. The A3010 model was intended to be a home computing machine, featuring a TV modulator and joystick ports, while the A3020 targeted the home office and educational markets, featuring a built-in 2.5" hard drive. Technically, the A4000 was almost identical to the A3020, only differing in memory and hard disk size, and, of course, looks.
Also in 1992, Acorn also introduced a laptop computer called A4 that featured an ARM3 processor like the A5000, even though it had a slightly lower clock speed, and a LCD screen capable of displaying a maximum resolution of 640 × 480 pixels in 16 levels of grey. However, it did feature a monitor port which offered the same display capabilities as an A5000. Curiously, it did not have a specific built-in pointing device, so users had to resort to the cursor keys or a conventional Acorn three-button mouse.
The A7000, despite its name being reminiscent of the Archimedes naming conventions, was actually a low-end Risc PC – the line of RISC OS computers that succeeded the Archimedes in 1994.
Significance and impact
The Archimedes was one of the most powerful home computers available during the late 1980s and early 1990s; its main CPU was faster than the stock 68000s found in the more popular Atari ST and Commodore Amiga machines.
Despite a technical edge having been fully realised upon the release of RISC OS 2 in 1989, the Archimedes only ever met a moderate success, becoming very much a 'minority' platform outside of niche markets (not unlike the Apple Macintosh). The education markets of the UK, Ireland and Australasia were among the platform's most dominant zones of importance, along with specialised professional work such as radio, medical and train station management and music publishing. The success of the Archimedes in British schools was due partly to the Computers for Schools scheme organised by the Tesco supermarket chain in association with Acorn, and most students/pupils in the aforementioned countries in the early 90s will have seen/used an Archimedes.
The platform was very unusual in that it was and still is largely unknown outside of a handful of countries where most of its sales occurred. Very few people in Asia or the USA have ever heard of the Archimedes.
By the early 1990s however, the UK educational market which had been Acorn's perennial "cash cow" was beginning to turn away from the Archimedes. Many schools (particularly in Scotland for example) were then turning to the Macintosh. Meanwhile, the IBM Compatible PC was gradually aligning itself as a potential contender with its increasing functionality as a multimedia computer, made possible by developments such as the Intel 486 processor.
See also
- BBC Micro predecessor
- Risc PC The next generation Archimedes
- Acorn Computers Ltd
External links
- Acorn Archimedes site
- arcem machine emulator released under the GNU GPL
- Archie Archimedes emulator (link broken)
- RedSquirrel ARM machine emulator
- Virtual Acorn - commercial Archimedes / RISC OS emulation package
- Acorn Archimedes memories
- Acorn Archimedes Emulator related site
- Castle Technology - Acorn's Hardware successor, producing the next generation RISC OS machines
- RISC OS Ltd - continuing the development of the RISC OS operating system
| List of Acorn Computers microcomputers |
|---|
|
Microcomputer System | Atom | BBC Micro (aka Proton) | Electron | Communicator | Business Computer | BBC Master | Archimedes range | Risc PC | Network Computer | Set-Top Box | Phoebe |