Osborne 1 Technical Manual
The Osborne 1 Technical Manual is Osborne Computer Corporation's technical reference for the Osborne 1, part number 2F00153-01, copyright 1982. The hosted scan has 589 PDF pages and a text layer. It covers the hardware, the monitor ROM and BIOS, and the theory of operation, with schematics and Osborne's own parts lists for the main logic board and the disk electronics board, followed by the manufacturers' data sheets and ROM and BIOS listings.
Contents
[edit | edit source]From the manual's contents pages:
- 1.0 Perspective, 1: introduction, power on, variations in design (board, ROM and BIOS revisions)
- 2.0 Logic board and CPU, 3: board revisions and layout, central processor
- 3.0 Memory scheme, 7: memory banks, CP/M memory allocation, memory-mapped I/O, access time
- 4.0 Interface design, 13: IEEE-488 (pinouts, use as a parallel port), RS-232, modem, baud rate
- 5.0 Video, 23: display, video memory, character generation, block graphics, video signals and timing
- 6.0 Power specifications, 31: the Astec supply, mains voltage switching, power board layout
- 7.0 Disk drives, 33: drives used, disk interface board revisions, controller and connector pinout, BIOS disk addressing, disk format
- 8.0 Keyboard, 41
- 9.0 Assembly and disassembly, 45: original and blue-case bezel, chassis and monitor, logic board, power supply, drives, power panel
- 10.0 Software, 63: ROM and BIOS revisions, monitor ROM, BDOS calls, BIOS routines
- 11.0 Theory of operation, 71
- 12.0 Schematics, 85: main logic board, and disk electronics board from 105
- Appendices: A, Z80 instruction set, 113; B, 6821 PIA, 121; C, 6850 ACIA, 135; D, MB8877A disk controller, 147; E, Osborne 1 system specifications, 161
- ROM and BIOS listings for versions 1.3 and 1.4
The Detached Lists of Materials are bound with the schematics: the Main Logic PCB Assembly, LM# 3A10063-06 (PDF pages 125 to 127), and the Disk Electronics PCB Assembly, LM# 3A03004-00, revision J, 22 June 1982 (PDF pages 132 and 133). Each gives the Osborne part number, quantity, description and reference designators of every part.
What this manual does not contain
[edit | edit source]- No parts list for the power supply or the monitor. Astec's component list for the AC8151 supply and Motorola's parts list for the MD1000-190 monitor are in the appendices of the Osborne Field Service Manual.
- No fault trees. Those are in chapter 7 of the Field Service Manual.
- The schematics are for the multilayer main logic board. The earlier board's drawing 1A2011-00 revision E is hosted separately as File:Osborne 1 Schematics 1A2011-00 Rev E.pdf.
- The text layer is unreliable on the schematic and parts-list pages; read values from the page images.
Pages that cite this document
[edit | edit source]- Osborne 1: CPU, memory, video, disk format, power supply ratings and fuse, board revisions
- Osborne 1 Capacitor Replacement Guide: the logic board and disk electronics board capacitor lists
- Osborne 1 Troubleshooting Guide: the logic board device map, ROM diagnostics, revisions
- Osborne 1 General Maintenance: mains voltage selection, supply ratings, drives
Download: Osborne 1 Technical Manual.pdf