Acorn A3010, A3020 and A4000 Service Manual
The Acorn A3010, A3020 and A4000 Module Level Service Manual is Acorn's dealer service manual for the Acorn Archimedes A3010, Acorn Archimedes A3020 and Acorn Archimedes A4000, part number 0494,059, ISBN 1 85250 109 X, Issue 1. The title page says September 1993; the contents and appendix footers say October 1993. All three machines use the ARM250, so Acorn covered them in one manual. The hosted scan has 42 pages and a searchable text layer.
Contents
[edit | edit source]Acorn's contents list, with printed page numbers:
- About this manual, p. v
- Part 1, Fault diagnosis and repair, p. 1-1: test equipment required 1-1, checking a "dead" computer 1-1 (action if PSU fails 1-3, action if main PCB fails 1-3, what to do next 1-4), checking a partly working computer 1-4, before the tests 1-5
- Part 2, Disassembly and assembly, p. 2-1: A3010/A3020 (top cover, keyboard, metal safety case, floppy drive, hard disc, speaker, PCB) 2-1; A4000 (top cover, speaker, drive tray, PCB, front moulding, PSU, floppy drive, hard disc) 2-3; main unit assembly 2-4
- Appendix A, mouse test jig template, p. A-1
- Appendix B, serial port loopback plug, p. B-1
- Appendix C, earth continuity testing, p. C-1, with separate procedures for the A4000 and the A3010/A3020
- Appendix D, DC insulation testing for class 1 equipment (UK only), p. D-1
- Appendix E, software testing, p. E-1: the ARM250 Dealer Test Disc (part 0294,825) functional tests for audio, battery-backed RAM, disc interface, external ports, hard disc, hardware check, IDE interface, joystick, keyboard and mouse, memory, real time, UHF modulator and video, each with the action to take on failure
- Appendix F, tools for software testing, p. F-1: backing up the test disc, validating the test equipment, creating a test IDE hard disc, saving and restoring the customer's CMOS RAM settings
What it settles
[edit | edit source]- Power supply faults (pp. 1-2 to 1-3). The +5 V rail feeds the main PCB, floppy drive and hard disc; +12 V feeds pin 12 of the video connector SK1 (for a SCART TV) and, on the A4000, the hard disc. For a suspected thermal shutdown on the A3010 and A3020, Acorn checks the internal fuse FS1 and then the continuity of the primary circuit, which should read about 4 Ω; an open primary means the transformer's internal thermal fuse has probably blown, and the board goes back for repair. A flowchart for complete supply failure on these two machines is Figure 1-2 (p. 1-6). The mains plug fuse is 3 A on the A3010 and A3020 (Figure 1-2) and 5 A on the A4000, and on the A4000 a supply that runs for a while and then cuts out has made a controlled thermal shutdown caused by a failed part inside the PSU.
- Checks before returning a main PCB (p. 1-3): ROMs in the right sockets with no lifted pins, the ROM links LK10, LK11, LK12 and LK14, the DRAM size links, socketed parts correctly oriented, and loose debris. The manual names the DRAM size links as LK23 and LK24, which are the A5000's numbers; the Technical Reference Manual links table (p. 1-20) gives LK20-LK22 on the A3010 and LK31 and LK32 on the A3020 and A4000.
- The power-on self-test (p. 1-3): a soft reset skips it; after power-on the screen colour changes as the test runs, faults are signalled by blinking the floppy drive LED, and a pass takes 2 to 12 seconds depending on memory. The POST sets a 15 kHz mode, so a VGA or multisync monitor shows an unsynchronised picture during it.
What this manual does not contain
[edit | edit source]Acorn wrote it for service centres that replace modules; boards needing component-level repair went to an Acorn Central Service Workshop (p. v). It has no circuit diagrams, parts lists or component values; those are in the Acorn A3010, A3020 and A4000 Technical Reference Manual. It does not document the power supply internally and gives no upgrade fitting instructions.
Pages that cite this document
[edit | edit source]- Acorn Archimedes A3010, Acorn Archimedes A3010 Maintenance Guide, Acorn Archimedes A3010 Troubleshooting Guide, Acorn Archimedes A3010 Capacitor Guide
- Acorn Archimedes A3020, Acorn Archimedes A3020 Maintenance Guide, Acorn Archimedes A3020 Troubleshooting Guide, Acorn Archimedes A3020 Capacitor Guide
- Acorn Archimedes A4000, Acorn Archimedes A4000 Maintenance Guide, Acorn Archimedes A4000 Troubleshooting Guide, Acorn Archimedes A4000 Capacitor Guide