Archimedes 300 Series Service Manual Component Level Supplement
The Archimedes 300 Series Service Manual Component Level Supplement is Acorn Computers' component-level companion to the Archimedes 300 Series Service Manual for the A305 and A310: part number 0476,145, issue 1, October 1988, 55 pages.[1] It adds the main PCB parts list, a longer system description, component-level fault-finding and test ROM procedures.
Contents
[edit | edit source]Page numbers are from the supplement's contents list.[2]
- 1. Introduction, p. 5
- 2. System description, p. 6: memory maps, IOC registers and interrupts, sound, the keyboard protocol and key mapping
- 3. Upgrades, p. 25
- 4. Fault-finding information, p. 28: basic checks; main PCB faults (video failure, system failure, unstable or scrolling display, corrupted display, colours incorrect or missing); peripheral faults (keyboard and mouse, floppy drive, printer, serial port, audio, configuration and real-time clock), p. 34; hard disc, podules, keyboard, audio; test ROMs, with a main memory test (p. 36) and a repetitive reset test (p. 37)
- 5. Appendices, p. 39: parts lists (p. 41), production and field changes (p. 45), and circuit diagrams of the hard disc podule (p. 49), MIDI podule (p. 51), Econet module (p. 53) and 2-way backplane (p. 55)
What it settles
[edit | edit source]| Part | Position | Acorn part no. |
|---|---|---|
| ARM (2 µm) | IC43 | 2201,365 |
| MEMC | IC45 | 2201,366 |
| VIDC 1A | IC17 | 2201,367 |
| IOC | IC21 | 2201,368 |
| Programmed PAL 16L8A | IC44 | 0276,032 |
| Arthur 1.2 ROMs | IC24-IC27 | 0277,022 to 0277,025 |
| 1772 floppy disc controller | IC47 | 0701,772 |
| 65C51 serial controller | IC9 | 0706,552 |
| PCF8583 clock and CMOS RAM | IC16 | 0708,583 |
| 4464 DRAM, 120 ns, 64K × 4 (16 off) | IC69-IC76, IC78-IC85 | 0704,105 |
| Tantalum 4.7 µF 10 V | C40 and the 18 positions marked 'B' | 0610,005 |
| Tantalum 10 µF 10 V | C14, C20, C35, C36, C52 | 0610,010 |
| Tantalum 100 µF 16 V | C37, C38, C39 | 0611,101 |
| Aluminium electrolytic, 16 V radial | C50 | 0635,221 |
| Decoupling 33/47 nF | 18 positions 'Z' (0.2 in) and 39 positions 'A' (axial) | 0680,002 and 0680,100 |
C50 is the only aluminium electrolytic on the main board. Its value is printed as "220p" in this copy; the Archimedes 440 Service Manual lists the same part number, 0635,221, as 220 µF 16 V.[3][4] The other lists give the PSU as part 0176,002, "55W 240V PSU", the battery holder as 0176,009, and the two AA cells as 0817,005, alkaline, 1.5 V, 2 Ah.[3]
The fault-finding section names parts. A dead system means changing in turn the ARM (IC43), MEMC (IC45), IOC (IC21) and VIDC (IC17) before tracing further. If the CMOS RAM loses its settings and the clock fails, IC16 pin 8 should read about 2.8 V with the computer off; if it does not, inspect PL11, D3 and the cells, each of which should be above 1.4 V. If the clock does not run or runs inaccurately, check crystal XL3; TP1 gives access to its signal.[5]
What it does not contain
[edit | edit source]The main PCB circuit diagram is in the module-level manual (PDF pp. 124-125). The PSU appears only as a module. Some designators are not in the parts list, for example C30, C34 and C41-C48. The PDF's text was produced by OCR (OmniPage), and values can carry recognition errors, as with C50.[3]
Pages that cite this document
[edit | edit source]- Acorn Archimedes A305 and Acorn Archimedes A310
- Acorn Archimedes A440
- Archimedes 300 Series Service Manual
Download: Archimedes 300 Series Service Manual Component Level Supplement.pdf (0.6 MB)
References
[edit | edit source]- ↑ Acorn Computers, High Performance Computer Systems 300 Series Service Manual Component Level Supplement, part 0476,145, issue 1, October 1988, cover and copyright page (PDF pp. 1-2). Hosted as File:Archimedes 300 Series Service Manual Component Level Supplement.pdf.
- ↑ 300 Series Component Level Supplement, Contents (PDF p. 3).
- ↑ 3.0 3.1 3.2 3.3 300 Series Component Level Supplement, section 5.1, Parts Lists, pp. 40-44 (PDF pp. 40-44).
- ↑ Acorn Computers, Archimedes 440 Service Manual, part 0476,155, section 7.1, Parts Lists, p. 58 (PDF p. 92). Hosted as File:Archimedes 440 Service Manual.pdf.
- ↑ 300 Series Component Level Supplement, section 4, Fault-finding information, pp. 32-34 (PDF pp. 32-34).