Tandy 1400LT - Table of Contents

CONTENTS
PART 1 .
1.1 .
1.2 .
1.3 .
1.4 .
PART II .
11.1 .
11.2 .
11.3 .
11.4 .
11.5 .
11.6 .
11.7 .
11.8 .
11.9 .
11.10 .
11-1 1 .
11-1 2 .
11.13 .
INTRODUCTION ................................................................................................ 1-1
System Overview ................................................................................................... 1-2
External View
.......................................................................................................... 1-2
Internal View
........................................................................................................... 1-4
Hardware Specifications
...................................................................................... 1-7
DISASSEMBLY I NSTR UCTlO NS .............................................................. 2-1
Top Case
................................................................................................................. 2-1
Battery Cover and Rear Cover
.......................................................................... 2-3
LCD Frame. Buttons. and LCD
........................................................................... 2-3
LED PCB and Keyboard
....................................................................................... 2-6
Battery Pack
........................................................................................................... 2-7
Base Frame
............................................................................................................. 2-7
Power Source PCB. Power Source PCB Cover and Power Source
FDD Cable. Expansion Bus Cable. Modem Cable and Memory Cable
..... 2-11
Contrast Knob
........................................................................................................ 2-12
Speaker
.................................................................................................................... 2-12
Main PCB. Keyboard Shield Plate. Rear Panel and Rear Panel Cover
..... 2-13
Pedestals. Handle and Bottom Case
................................................................ 2-14
FDD
........................................................................................................................... 2-9
PCB BOX
................................................................................................................... 2-10
PART 111 . PREVENTIVE MAINTENANCE ................................................................ 3-1
111.1 . To Clean the Body and LCD Display ................................................................ 3-1
111.2
. RTC (Real Time Clock) Frequency Adjustment ............................................. 3-1
111.3
. LCDC Frequency Adjustment ............................................................................. 3-1
PART IV . THEORY OF OPERATION ......................................................................... 4-1
IV-1 . General ..................................................................................................................... 4-1
IV.2
. Block Diagram ........................................................................................................ 4-2
IV.3
. Description of Block Diagram ............................................................................ 4-3
IV.5
. Clock Generator (Custom IC) ............................................................................. 4-4
IV.7
. RAM Control Circuit .............................................................................................. 4-8
IV.8
. MEMORY Card Specification .............................................................................. 4-10
IV.9
. ROM Control Circuit .............................................................................................. 4-11
IV.10
. I/O Address Map ................................................................................................... 4-12
IV.4
. CPU ........................................................................................................................... 4-4
IV.6
. MEMORY MAP ........................................................................................................ 4-7