Josh at 08:47, 19 July 2026

2026-07-19T08:47:03Z

← Older revision		Revision as of 09:47, 19 July 2026
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	\| model = AGB22, AGB23, AGB33		\| model = AGB22, AGB23, AGB33
	}}		}}
	The '''Acorn Archimedes A3020''' is an all-in-one 32-bit computer that [[Acorn Computers]] announced in August 1992 and shipped from September 1992. It was the education member of a three-machine range built around the ARM250 processor, sold alongside the home-market [[Acorn Archimedes A3010\|A3010]] and the three-box [[Acorn Archimedes A4000\|A4000]].<ref name="chris">Whytehead, Chris. [https://chrisacorns.computinghistory.org.uk/Computers/A3020.html "Acorn A3020"], Chris's Acorns / The Centre for Computing History.</ref><ref name="arcwiki">[https://arcwiki.org.uk/index.php/A3020 "A3020"], Arc Wiki.</ref>		The '''Acorn Archimedes A3020''' is an all-in-one 32-bit computer that Acorn Computers announced in August 1992 and shipped from September 1992. It was the education member of a three-machine range built around the ARM250 processor, sold alongside the home-market [[Acorn Archimedes A3010\|A3010]] and the three-box [[Acorn Archimedes A4000\|A4000]].<ref name="chris">Whytehead, Chris. [https://chrisacorns.computinghistory.org.uk/Computers/A3020.html "Acorn A3020"], Chris's Acorns / The Centre for Computing History.</ref><ref name="arcwiki">[https://arcwiki.org.uk/index.php/A3020 "A3020"], Arc Wiki.</ref>

	The A3020 replaced the [[Acorn Archimedes A3000\|A3000]] in schools. It kept the A3000's integrated-keyboard format but added a faster processor, an on-board IDE interface for a fitted hard disc, and a dedicated network socket for classroom use.<ref name="chris" />		The A3020 replaced the [[Acorn Archimedes A3000\|A3000]] in schools. It kept the A3000's integrated-keyboard format but added a faster processor, an on-board IDE interface for a fitted hard disc, and a dedicated network socket for classroom use.<ref name="chris" />

Josh: Add dimensions/weight to infobox (fix leading whitespace)

2026-07-18T13:50:18Z

Add dimensions/weight to infobox (fix leading whitespace)

← Older revision		Revision as of 14:50, 18 July 2026
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	\| display = Analogue RGB, 15-pin VGA-type connector		\| display = Analogue RGB, 15-pin VGA-type connector
	\| sound = 8-channel, 8-bit logarithmic (VIDC1a)		\| sound = 8-channel, 8-bit logarithmic (VIDC1a)
			\| dimensions = 479 mm × 267 mm × 73 mm
			\| weight = approx. 4 kg
	\| os = RISC OS 3.11		\| os = RISC OS 3.11
	\| predecessor = [[Acorn Archimedes A3000]]		\| predecessor = [[Acorn Archimedes A3000]]

Josh: Create Acorn Archimedes A3010/A3020 page set (researched, cited)

2026-07-18T13:44:11Z

Create Acorn Archimedes A3010/A3020 page set (researched, cited)

New page

{{Infobox computer
| name = Acorn Archimedes A3020
| image = [[File:Acorn Archimedes A3020.jpg|250px]]
| caption = Acorn Archimedes A3020 with colour monitor
| manufacturer = Acorn Computers Ltd
| type = Personal computer (education)
| release date = September 1992
| discontinued = 1995
| price = From £749 ex VAT (2 MB, floppy) with monitor
| cpu = ARM250 @ 12 MHz
| memory = 2 MB RAM (expandable to 4 MB)
| storage = 3.5" floppy (1.6 MB); optional 2.5" IDE hard disc
| display = Analogue RGB, 15-pin VGA-type connector
| sound = 8-channel, 8-bit logarithmic (VIDC1a)
| os = RISC OS 3.11
| predecessor = [[Acorn Archimedes A3000]]
| successor = [[Acorn A7000]]
| codename = Heron E
| model = AGB22, AGB23, AGB33
}}
The '''Acorn Archimedes A3020''' is an all-in-one 32-bit computer that [[Acorn Computers]] announced in August 1992 and shipped from September 1992. It was the education member of a three-machine range built around the ARM250 processor, sold alongside the home-market [[Acorn Archimedes A3010|A3010]] and the three-box [[Acorn Archimedes A4000|A4000]].<ref name="chris">Whytehead, Chris. [https://chrisacorns.computinghistory.org.uk/Computers/A3020.html "Acorn A3020"], Chris's Acorns / The Centre for Computing History.</ref><ref name="arcwiki">[https://arcwiki.org.uk/index.php/A3020 "A3020"], Arc Wiki.</ref>

The A3020 replaced the [[Acorn Archimedes A3000|A3000]] in schools. It kept the A3000's integrated-keyboard format but added a faster processor, an on-board IDE interface for a fitted hard disc, and a dedicated network socket for classroom use.<ref name="chris" />

== Positioning ==

Acorn aimed the A3020 at primary and middle schools. It shipped in the traditional BBC-beige case with red function keys, and every unit carried an on-board IDE controller so that a machine could be supplied floppy-only or with an internal hard disc.<ref name="chris" /> A rear network socket allowed the A3020 to work peer-to-peer or as a station on a client/server network without using the internal expansion slot.<ref name="netif">[https://chrisacorns.computinghistory.org.uk/docs/Acorn/DN/Acorn_A3020A4000NwIfSpecIss1.pdf "A3020/A4000 Network Interface Specification"], Acorn Computers Ltd.</ref>

Launch prices, quoted with a colour monitor and excluding VAT, were £749 for the 2 MB floppy-only model and £899 for the 2 MB machine with a 60 MB hard disc.<ref name="arcwiki" /><ref name="mcmordie">[https://www.mcmordie.co.uk/acornhistory/a3ka4k.shtml "A3010, A3020 and A4000"], Acorn history pages.</ref>

== Processor ==

The A3020 uses the '''ARM250''' clocked at 12 MHz. The ARM250 was Acorn's first ARM system-on-chip: it integrates onto one die the four devices that were separate on the [[Acorn Archimedes A3000|A3000]] — an ARM2-class processor core, the MEMC1a memory controller, the VIDC1a video and sound controller, and the IOC input/output controller.<ref name="wp">[https://en.wikipedia.org/wiki/Acorn_Archimedes "Acorn Archimedes"], Wikipedia.</ref> The core is cacheless (ARM2-class), so the A3020 delivers roughly 7 MIPS — about the same as the A3000's discrete chipset would at 12 MHz, but well short of the ARM3-based [[Acorn Archimedes A5000|A5000]].<ref name="wp" /><ref name="chris" />

Running the memory at 12 MHz with 80 ns DRAM, against the A3000's 8 MHz and 125 ns parts, gives the machine its performance step over its predecessor.<ref name="chris" /><ref name="wp" /> A Chips & Technologies '''82C711''' peripheral controller provides the IDE, floppy, serial and parallel interfaces in a single support chip.<ref name="82c711">[https://arcwiki.org.uk/index.php/82C711 "82C711"], Arc Wiki.</ref>

== Memory and firmware ==

The A3020 ships with 2 MB of RAM and accepts a 2 MB upgrade board fitted into the on-board ZIP DRAM sockets, reached through a hole in the RF shield, for a 4 MB maximum.<ref name="chris" /><ref name="arcwiki" /> RISC OS is held in 2 MB of ROM (two devices); production machines carry RISC OS 3.11, with some early units on 3.10.<ref name="chris" /><ref name="riscos">[https://en.wikipedia.org/wiki/History_of_RISC_OS "History of RISC OS"], Wikipedia.</ref>

== Storage ==

The floppy drive is a 3.5-inch high-density unit, formatted to 1.6 MB under the ADFS "F" format and driven by the 82C711.<ref name="trm">[[Acorn A3010, A3020 and A4000 Technical Reference Manual]], Acorn Computers Ltd — hosted on this wiki.</ref> The on-board IDE interface, terminating at connector PL1, supports one internal 2.5-inch drive; launch machines used a 60 MB unit, and an 80 MB education variant followed.<ref name="chris" /><ref name="trm" /> This on-board IDE is one of the main differences from the A3000, which had no built-in hard-disc support.<ref name="wp" />

== Ports and expansion ==

The rear panel carries, from left to right, a parallel printer port, a serial port, a network socket, a mouse port, a headphone socket and the analogue RGB video output, with the power switch at the right.<ref name="chris" /> The video connector is a 15-pin VGA-style socket carrying analogue RGB, the same connector used by the [[Acorn Archimedes A5000|A5000]]; the A3020 has no TV modulator.<ref name="videospec">[https://chrisacorns.computinghistory.org.uk/docs/Acorn/Tech/Acorn_A3xA4xVideoSpec.pdf "A3xx/A4xx Video Specification"], Acorn Computers Ltd.</ref>

Internally the machine has one mini-podule expansion slot, mechanically compatible with A3000 upgrade cards, plus a separate network-interface slot that takes an Econet or Ethernet module and feeds the rear network socket.<ref name="trm" /><ref name="netif" /> Econet is not fitted as standard.<ref name="chris" /> The A3020 has no joystick ports; the network connector occupies the position used for the joystick ports on the A3010.<ref name="trm" />

== Case and power ==

The A3020 is a single-box machine with the computer built into a sloping keyboard case, roughly 479 × 267 mm and 73 mm high, weighing about 4 kg.<ref name="chm">[https://www.computerhistory.org/collections/catalog/102743327 "Acorn A3010 (shared case)"], Computer History Museum catalogue.</ref> The mains power supply is built onto the main PCB rather than being a removable module, and the service documentation records two supply rails, +5 V and +12 V; the +12 V rail also appears on pin 12 of the video connector for SCART switching.<ref name="sm">[[Acorn A3010, A3020 and A4000 Service Manual]], Acorn Computers Ltd — hosted on this wiki.</ref>

== Differences from the A3010 and A4000 ==

All three 1992 machines share essentially the same main-board design.<ref name="wp" /> The A3020 differs from its siblings as follows:

{| class="wikitable styled-table" style="width:90%; text-align:left;"
! Feature !! A3020 (education) !! A3010 (home) !! A4000 (professional)
|-
| Case || Single box, beige, red keys || Single box, grey, green keys || Three box, separate keyboard
|-
| Hard disc || On-board IDE, optional 2.5" drive || None fitted || On-board IDE, 3.5" drive standard
|-
| Network socket || Yes || No || Yes
|-
| TV modulator || No || Yes || No
|-
| Joystick ports || No || Two (9-pin) || No
|-
| RAM as sold || 2 MB || 1 MB (base) || 2 MB
|}

Sources: Chris's Acorns and Wikipedia.<ref name="chris" /><ref name="wp" />

== Circuit diagrams and PCB ==

The A3020 main board is part 0194,500, codenamed "Heron E". Acorn documented the machine at module level in the [[Acorn A3010, A3020 and A4000 Service Manual|Service Manual]]; the component-level circuit diagrams are in the [[Acorn A3010, A3020 and A4000 Technical Reference Manual|Technical Reference Manual]], both hosted on this wiki.

{| class="wikitable styled-table" style="width:80%; text-align:center;"
! Main PCB !! Circuit diagram (sheet 1 of 3)
|-
| [[File:Acorn Archimedes A3020 motherboard.jpg|400px]] || [[File:Acorn Archimedes A3020 circuit diagram (1 of 3).png|400px]]
|-
! Circuit diagram (sheet 2 of 3) !! Circuit diagram (sheet 3 of 3)
|-
| [[File:Acorn Archimedes A3020 circuit diagram (2 of 3).png|400px]] || [[File:Acorn Archimedes A3020 circuit diagram (3 of 3).png|400px]]
|-
! PCB assembly (designators) !!  
|-
| [[File:Acorn Archimedes A3020 PCB assembly.png|400px]] ||  
|}

== Discontinuation ==

Acorn ceased A3020 production in 1995, with remaining stock sold into 1996; the machine did not conform to newly introduced European electrical regulations.<ref name="arcwiki" /><ref name="wp" /> Its role passed to the [[Acorn A7000]].

== General maintenance ==
{{Main|Acorn Archimedes A3020 Maintenance Guide}}

The dominant maintenance job on any surviving A3020 is dealing with the soldered NiCd backup battery, which leaks and corrodes the board around it. The on-board mains PSU and the ageing 2.5-inch hard disc are the other priorities. See the [[Acorn Archimedes A3020 Maintenance Guide]].

== Troubleshooting ==
{{Main|Acorn Archimedes A3020 Troubleshooting Guide}}

Most faults trace to battery corrosion, the on-board PSU, or a monitor-type mismatch that produces no picture on an otherwise healthy machine. Because the ARM250 integrates the processor, memory, video and I/O controllers, a fault inside it is a whole-device replacement. See the [[Acorn Archimedes A3020 Troubleshooting Guide]].

== Capacitor guide ==
{{Main|Acorn Archimedes A3020 Capacitor Guide}}

The A3020 board is mostly leaded electrolytics with a small number of surface-mount aluminium electrolytics, and is not a routine "recap" machine; the battery, not the capacitors, is the usual source of corrosion. See the [[Acorn Archimedes A3020 Capacitor Guide]].

== See also ==

* [[Acorn Archimedes A3010]] — home-market sibling
* [[Acorn Archimedes A4000]] — three-box sibling
* [[Acorn Archimedes A3000]] — predecessor
* [[Acorn Archimedes A5000]] — ARM3 flagship of the same era

== References ==

<references />

{{Navbox-AcornComputers}}

[[Category:Acorn Computers]]
[[Category:1992 Computers]]

Acorn Archimedes A3020 - Revision history

Josh at 08:47, 19 July 2026

Josh: Add dimensions/weight to infobox (fix leading whitespace)

Josh: Create Acorn Archimedes A3010/A3020 page set (researched, cited)