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TRS-80 Model II
Technical reference manual
Tandy TRS-80 Model II Technical Reference Manual
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Also See for TRS-80 Model II
:
Owner manual & programming manual
(104 pages)
,
Service manual
(60 pages)
,
Owner's manual
(16 pages)
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Table Of Contents
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Contents
Table of Contents
Troubleshooting
Bookmarks
Table of Contents
An Overview
Table of Contents
List of Illustrations
System Description
Introduction
Video Display Console
Case
Chassis
Keyboard Unit
Peripheral Interfaces
Floppy Disk Controller Card
Memory Card
Block Diagram
Power Distribution Block Diagram
Power Distribution Schematic
Troubleshooting/Replacement
Bootstrap Sequence
Detailed Troubleshooting Instructions
Software Diagnostics
Sync Signals
Replacement Procedures
System Disassembly
Video Display and Video Board
Disk Drive
Keyboard
Fan
Replacement Parts List
CPU Module
Functional Specifications
Theory of Operation
Decoding Logic
Port Address Allocation
Bus Steering Logic
Wait State Generation Logic
Manual and Power on Reset Logic
System Clock Generation Logic
Interrupt Priority Logic
EIA Buffers
Connector J1 Signal Descriptions
CPU Module Parts List
Floppy Disk Controller
Bus Interface Logic
PIO Interface Logic
Floppy Disk Controller IC
Processor Interface
Floppy Disk Interface
Head Positioning
Disk Read Operations
Stepping Rates
Disk Write Operations
FDC and FDD Interface Logic
Recording Codes
Self-Clocking Codes
Read Clock Recovery Logic
Clock Recovery Block Diagram
Write Compensation
Interacting Clock / Data Pulses
Write Compensation Logic
Jumper Options
BIT Allocation
J1 Signal Descriptions
Floppy Disk Controller Parts List
Video/Keyboard Interface
High Speed Timing
Cathode Ray Tube Controller
CRT Control
Refresh Memory/Character Generator Addressing
Other Pins
Character Dot Pattern
Multiplexers
Ram/Video RAM Select Logic
Video Board Select Logic
Port Addressing
Other Blocks
Keyboard Timing Diagram
Connector J2 Signal Descriptions
Connector J3 Signal Descriptions
Video/Keyboard Interface Board Parts List
Memory Board
Video Monitor
Troubleshooting Guide
Video Amplifier
Horizontal Driver
Horizontal Output Transformer
Vertical Deflection
Horizontal Drive Signal
Preliminary Checkout
Cathode Ray Tube
Monitor Circuit Card
General Servicing Precautions
Video Wiring Harness
Video Monitor Parts List
Floppy Disk Drive
Jumper Configuration
Disk Termination
Disk Drive Mechanical Parts List
Power Supply
No Output
Load Board Values
Test Lay out
Output Connector
Operating Characteristics
Card Cage and Motherboard
Card Cage and Motherboard Parts List
Keyboard Internal Cable
Keyboard External Cable
Keyboard Parts List
Serial Interface Connections
Parallel Interface
Parallel Interface - Signal Descriptions
Disk Expansion Connector
Rear View
Disk Expansion Unit
Troubleshooting - Disk System
AC or DC Power Failures
Operational Failures
Read or Write Error
Disk Expansion Unit Wiring Diagram
Parts List
Disk Drive Electrical Parts List
Illustrated Parts Breakdown
Case Assembly Parts List
Case Assembly
Chassis Assembly Parts List
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See also:
Service Manual
,
Operating Manual
Table of
Contents
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Table of Contents
Troubleshooting
Troubleshooting/replacement
18
Bootstrap sequence
20
Troubleshooting guide
111
Troubleshooting - disk system
172
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