Radio Shack TRS-80 III - Page 5

SECTION
NUMBER
TABLE OF CONTENTS (Cont'd)
PAGE
NUMBER
fiGURE
NUMBER
final Check .
Disk Controller Board Parts
list .
Servo Board Parts
list {Non-linear} .
Servo Board Parts
list {linear} .
Illustrated Parts Catalog Parts
list .
LIST OF ILLUSTRATIONS
TITLE
SECTION 1- INTRODUCTION
111
112
116
117
119
PAGE
NUMBER
1
2
3
4
4
5A
5B
5C
50
5E
5F
5G
5H
5J
5K
1
2
2
3
TRS-80 Model III Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
SECTION
III - CPU CIRCUIT BOARD
CPU Timing Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Video Timing
Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
10
Bus Timing Diagram ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
CPU Printed Circuit Board - Component Side . . . . . . . . . . . . . . . . . . . .. 23
CPU Printed Circuit Board - Circuit Side ., . . . . . . . . . . . . . . . . . . . . .. 24
Model
III CPU Schematic Diagram -
Video and Horizontal Sync Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
Model III CPU Schematic Diagram - Processor Section. . . . . . . . . . . . . .. 32
Model
III CPU Schematic Diagram - RAM Section. . . . . . . . . . . . . . . . .. 33
Model
III CPU Schematic Diagram -
Address Decoding Section 34
Model
III CPU Schematic Diagram - Video Section 35
Model
III CPU Schematic Diagram - Keyboard Section. . . . . . . . . . . . . .. 36
Model
III CPU Schematic Diagram-
Cassette Interface Section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 37
Model
III CPU Schematic Diagram --
line Printer and Real Time Clock Section .. . . . . . . . . . . . . . . . . . . . . . 38
Model II I
CPU Schematic Diagram - I/O Bus Section . . . . . . .. 39
Model
III CPU Schematic Diagram -
RS-232C Interface and FDC Interface
Connections. . . . . . . . . . . . . . . .. 40
SECTION
IV - FLOPPY DISK INTERFACE
FDC Board
to CPU Board Signal Description . . . . . . . . . . . . . . . . . . . . . . 46
Floppy Disk Interface PC Board - Component Side .. , . . . . . . . . . . . . .. 47
Floppy Disk Interface
PC Board - Circuit Side 48
Model
III Floppy Disk Interface Schematic . . . . . . . . . . . . . . . . . . . . . .. 61