Tandy 1000 Technical Reference Manual

Tandy 1000
TABLE OF CONTENTS
Technical Reference Manual
Title Page
SECI'ION 3 THEORY OF OPERATION ••••••.••...•••••.••••.•..•.•..••.••...... 300
3-1 CONSTRUCI'ION AND FUNCI'ION •..••...•••••....•••..•••..•.•.•.•...•••. 301
3-1-1 General Block Diagram ••.•••.•..••....•••••.•..•..•••••.. •••·••·• 301
3-1-2 Mechanical Section ...•••..•..•..•.•.......•.•.••.•..•••..••••.•. 302
3-2 CIRCUIT DESCRIPTIONS ...•.••.••...••.•.•.•.•.•.•••.•..•..••.•....•. 307
3-2-1 Read write Circuit ...•..•••..•.••...•••.•.•.........•• ·····•·••· 307
3-2-2 Control Circuit ...........••...••...•..••...•.•....•..• ·••···•·· 315
3-2-3 Servo Circuit •.............•...•.....•......••........•• ••·····• 320
3-3 FUNCTION OF TEST POINTS AND VARIABLE RESISTORS ....•........•...••. 321
3-3-1 Function of Test Points .....•..••.....••....•••....•...••••....• 322
3-3-2 Function of Variable Resistors •.•••.••.••••.•.•.•••.•••..•.•.••• 329
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Tandy 1000 Specifications

General

Processor	Intel 8088
Processor Speed	4.77 MHz
RAM	128 KB (expandable to 640 KB)
Operating System	MS-DOS 2.11
Manufacturer	Tandy Corporation
Release Year	1984
Storage	Single or double 5.25" floppy disk drive (360 KB), optional hard drive
Sound	Tandy 3-voice sound
Ports	Parallel, Serial
Graphics	CGA (Color Graphics Adapter)
Graphics Modes	320x200, 640x200