Service manual

Service Manual
Contents
About this manual vi
Part 1 - System description 1-1
Introduction 1-1
General 1-1
System timing 1-2
The I/O system 1-3
The sound system 1-9
The keyboard and mouse 1-10
Floppy disc drive 1-14
Power supply 1-15
Hard disc drive 1-15
Main PCB Links 1-17
Plugs 1-18
Sockets 1-18
Internal expansion 1-19
Part 2 - Interface cards 2-1
Ethernet interface 2-1
Overview 2-1
Ethernet I expansion card 2-1
Ethernet II expansion card 2-13
SCSI interface 2-18
Part 3 - Disassembly and assembly 3-1
Introduction 3-1
Removing the top cover 3-1
Removing the SCSI podule 3-1
Removing cables 3-2
Removing the backplane 3-2
Removing the RAM and ARM cards 3-2
Removing the main PCB 3-2
Removing the front moulding assembly 3-2
Removing the floppy disc drive 3-2
Removing the hard disc drive 3-2
Removing the power supply unit 3-2
Main unit assembly 3-3
Keyboard 3-3
Mouse 3-3
Contents Issue 2, June 1991
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