BBC Master Series Documentation
Acorn documents for the BBC Master series. The service manual has its own page, BBC Master Series Service Manual. The Master Compact's service manual is on BBC Master Compact Service Manual, and the Turbo co-processor's user guide on Acorn 65C102 Co-Processor User Guide.
Master series technical drawings
[edit | edit source]File:Acorn BBC Master Series Technical Drawings.pdf joins six Acorn engineering drawings, scanned at 300 dpi, into one six-page PDF. The service manual reproduces the same drawings on A4 at a much lower resolution; these are the ones to read component values from.
| PDF page | Drawing | Number |
|---|---|---|
| 1 | Master 128 main PCB circuit diagram, sheet 1 of 2 (CPU, memory controller, ROMs, DRAMs, video, UHF modulator, cartridge sockets, internal Tube connector) | 0143,000/C |
| 2 | Master 128 main PCB circuit diagram, sheet 2 of 2 (disc, printer, user port, 1 MHz bus, Tube, keyboard encoder, 146818 clock, sound, serial, cassette, analogue port, Econet socket, supply input filters) | 0143,000/C |
| 3 | Keyboard (plain) "Project B" PCB circuit diagram, sheet 10 of 10 | 0143,201/T |
| 4 | Master Series 128 and E.T. final assembly | Number not legible on the scan |
| 5 | EPROM cartridge circuit diagram | A2/0143,040/C |
| 6 | 80186 co-processor circuit diagram (the Master 512 board) | 0143,200/C |
The drawings carry no power supply diagram and no circuit for the 65C102 co-processor or the Econet module. The revision box on the main board drawing runs from issue D (23 July 1985, redrawn on two sheets) and E (13 September 1985) to issue 1 (24 October 1985, AMR E075) and issue 2 (10 February 1986, ECO E107).
Download: Acorn BBC Master Series Technical Drawings.pdf
Hardware specification
[edit | edit source]File:Acorn BBC Master Series Hardware Specification.pdf is an undated 50-page Acorn document with an OCR text layer; Chris's Acorns lists it as February 1986. It brings together four items:
| Pages | Section |
|---|---|
| 1–16 | Hardware specification: core machine, memory map, internal and external I/O (the same text as section 5 of the service manual) |
| 17–33 | The Master 128 Repair Guide ("What to do if..."), an earlier and shorter form of the service manual's fault finding, with checks such as listening for a ticking power supply and the CTRL G beep test |
| 34–45 | 65C102 co-processor user guide: fitting, configuration, memory, HiBASIC, HiEDIT and the BUFFER utility |
| 46–49 | Fitting an ECONET module: support posts, SK5 and SK6, the ANFS ROM in IC27, links LK18 and LK19 |
| 50 | Additional information relating to Master Repair Guide: four field fixes (loss of configuration, mode 7 break-up, crashes when warm, no composite colour) |
It has no parts list, circuit diagram or power supply data. The field fixes on page 50 are not in the service manual and are the source for the table on BBC Master 128 Troubleshooting Guide#Acorn's field fixes.
Download: Acorn BBC Master Series Hardware Specification.pdf
Master series battery unit leaflets
[edit | edit source]Acorn's leaflet Master Series Battery Unit, part number 0443,900, replaces page 242 of the Master Welcome Guide. Two issues are hosted:
- Issue 1, January 1987 (2 pages, retyped text): Masters "are now fitted with a 4.5V battery unit instead of one 3.0V lithium cell"; old-style (holder on a metal plate, two screws, between the main board and the supply) and new-style (three shrink-wrapped cells beside the keyboard) units; black lead to the north pin of PL8 and red to the centre pin.
- Issue 3, May 1993 (4 pages): the same procedure, with battery life of about a year, an instruction to replace the batteries at least every 18 months to avoid leakage damage, and the statement that the PL8 connector may go either way round provided it covers all three pins.
Neither leaflet names the cell chemistry; both say the lithium handling warnings in the Welcome Guide generally apply.
Master AIV documents
[edit | edit source]- The BBC Master AIV User Guide, part number 0461,001, issue 1, October 1986 (78 PDF pages, OCR text): unpacking and connecting the AIV system; switching on with SHIFT, Q, CTRL and BREAK; a fault-finding checklist (printed pp. 4–6); the Domesday Project; the Video Filing System and its commands; video mixing modes; trackerball commands; programming notes; the SCSI interface.
- Special Instructions for Replacing Batteries on the BBC Master AIV Computer, part number 0461,004, issue 1, October 1986 (2 pages): three 1.5 V cells in a nest under the computer near the auxiliary power outlet, behind a cover with one large-headed screw; the holder is made for Duracell MN1500 cells. Scanned by BeebMaster; this copy has handwritten notes by an earlier owner.
Other documents
[edit | edit source]- File:Acorn 65C102 Internal Co-Processor Schematic (Simon Inns).pdf: Simon Inns's five-sheet redraw (2019, CC BY-SA 4.0) of the 65C102 co-processor board used in the Master Turbo and Master AIV. It is a modern reconstruction, not an Acorn drawing; Acorn's own documents give no circuit for this board.
- File:Acorn Master 512 leaflet Open Up to the World of MS-DOS (APP110).pdf: Acorn's four-page leaflet APP110 for the Master 512 upgrade.
What these documents do not contain
[edit | edit source]- A circuit diagram, parts list or ratings for the Master power supply. Neither the service manual nor any of these documents has one.
- A parts list for the Econet module or the co-processor boards.
Pages that cite these documents
[edit | edit source]- BBC Master 128, BBC Master 128 Maintenance Guide, BBC Master 128 Troubleshooting Guide and BBC Master 128 Capacitor Replacement Guide: circuit diagram, field fixes, battery leaflets, Econet fitting
- BBC Master 512: the 80186 co-processor circuit diagram and leaflet APP110
- BBC Master AIV: the AIV user guide and battery instructions
- BBC Master ET: the final assembly drawing