Tandy 2000 Service Manual page 4

Tandy@
Model
zfigg
Service
Manual
Table Of
Contents
Introduction
Specifications
....,
7
.1
Physical
Characteristics
7
.2
System
Operating
Characteristics
7
.3
Peripheral
Interfaces
7
.4
Optional
Features
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2
2
2
2
2
3
3
3
3
3
3
.1
.1
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.2
.3
7.1.1
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.L.2
7.1.3
7
.L.4
7
.L.4
7
.L.4
7
.L.4
7.1.5
7
.L.6
7
.L.7
7.1.8
7.1.9
General
Disassenbly,/assenbly
.....
........
Main
Unit
.1 Power Supp1y orrro
.2
Disk Drives
Keyboard
Assembly
Display
Unit
9
9
Lg
11
L2
13
39
39
39
41
42
43
43
q/ Adjustments
.
15
4.L
Power
Supply
15
4.2
PLL
Adjustment
15
4.3
Video
Adjustment..
15
S/
Cabling
Diagram,/Pinout
Connections
17
5
Troubleshooting
Procedures
6.
I
Power Supply
6.2
Other
Components
7/
Theory
of
Operation
Block
Diagram
7
.L Main Logic
Board
CPU
44
Bus
Interface ...:.
Sfi
video System
58
.1
Video
System
Theory
Of
Operation
69
.2
Address
Control Register
63
.3
Character
Attributes Byte
64
Character
Generator
66
Boot ROM/Interrupt
Controller
68
Clock/Pr,r,
72
timing
and
Control Circuits
77
.1
l'lemory
Control Overview
77
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