Tandon TM100-1 Service manual

OEM
OPERATING AND SERVICE MANUAL
TM-100-1 AND -2 DISK DRIVES
48 TRACKS PER INCH
I an aD n CORPORATION
20320 PRAIRIE STREET
CHATSWORTH, CA
91311
TELEPHONE [phone]
TWX 910 493 5965 ©COPYRIGHT 1981 TANDON CORPORATION

The information contained in this document is the property
of Tandon Corporation.
It may not be duplicated in full or part
by any person without prior written approval.
The material
in this document is provided for informational
purposes, and is subject to change by Tandon Corporation.

Section
Number Title of Section
TABLE OF CONTENTS
Page
Number
SECTION I- INTRODUCTION TO THE TM-100-1 AND -2 DISK DRIVES, 48 TPI
1.
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
1.10
1.10.1
1.11
1. 11.1
1.11.2
1.11.3
1.12
1.13
1.14
1.15
1.16
1.16.1
1.16.2
1.16.3
1.16.4
1.16.5
1.16.6
1.16.6.1
1.17
1.17.1
1.17.2
1.18
1.18.1
1.18.2
1.19
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-1
Purpose of The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Physical Description of The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Functional Description of The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Diskettes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Mechanical and Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Interface Circuit Specifications
........................................ ..... 1-2
Uncrating The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Physical Checkout of The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Interface Connections .................................................... 1-4
Chassis Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Isolated Ground
...... . . ...... ........ .. . ................................ 1-5
Mounting The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Dust Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Cooling System Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Diskette Care, Handling, and Storage
.............................. ... .. . .... 1-6
Write Protect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
-6
Operation of The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
Organization of The Disk Drive .
...... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Components of The Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Index Pulse
........................................ . ................... 1-7
Write Protect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1- 7
Track 00 Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Spindle Drive System
......................... . ......................... . 1-7
Positioner Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Data Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Data Recording . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Interface Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-11
Interface Connector Pin Assignments, J1 / P1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Power Connector Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Option Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Input Line Terminations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Drive Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
Power Save Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
SECTION II -MAINTENANCE CHECKS AND ADJUSTMENTS
2. Introduction . .. ....... .... ..... . .... ....... ... : . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1 Drive Motor Checks and Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1.1 Long-Term Drive Motor Speed Checks and Adjustment ..................... .... . 2-1
2.1 .2 Instantaneous Speed Variation Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.2 Cats Eye Alignment Check and Adjustment
................................... 2-3
2.2.1 CE Alignment Ctieck . . .. ... .................... . .... . . . ........ . .... ..... 2-3
2.2.2 Head Adjustment
....... .... . .. ... . ......... . ............................ 2-6

Section
Number Title of Section
TABLE OF CONTENTS
Page
Number
SECTION II -MAINTENANCE CHECKS AND ADJUSTMENTS
2.2.3 Track 00 Stop Adjustment .. ......... .. . ... . ............ . .................. 2-6
2.3 Index Checks and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
2.3.1 Index Checks
........ . .. . .. ..... .. . .......... . ... . ......... ............ 2-8
2.3.2 Index Adjustment
............................... .... ............. . ...... 2-9
2.4 Compliance Check and Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9
2.4.1 Compliance Check
.................................................. . ... 2-9
2.4.2 Compliance Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-11
2.5 Write Protect Switch Adjustment Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
SECTION Ill -PRINTED CIRCUIT BOARD OPERATION
3.
3.1
3.2
3.3
3.3.1
3.3.1.1
3.3.1 .2
3.3.1.3
3.3.1.4
3.3.1.5
3.3.1.6
3.3.2
3.3.2.1
3.3.2.2
3.3.2.3
3.3.2.4
3.4
3.4.1
Introduction
................. ..... .. . . . ............... . .. . ...... ... .. ... 3-1
Explanation of Symbols and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Physical Description of The Logic PCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Interface Electronics Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Input Control Lines .
...... . . .. .... ............. . .................. .. . .. .. 3-4
Select Lines (NDS0-NDS3)
.............. . ............. ... ................. 3-5
Drive Motor Enable
(N MOTOR ON) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Direction and Step Lines (DIR)
(N STEP) ........ . . .......................... 3-7
Write Enable
(N WRITE ENABLE) .......................................... 3-9
Write Data
(N WRITE DATA) ..... ... .. ...... ............... . .............. 3-9
Side Select N SIDE SELECT)
............................................. 3-10
Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
Index
(N INDEX/SECTOR) ................................. ...... ........ 3-13
Track 00
(N TRK 00) ............ ....................... .. .. . . .. . ... ..... 3-14
Write Protect
(N WRITE PROTECT) ... .................. . ............... ... 3-14
Read Data
(N READ DATA) ..................................... . .. ....... 3-15
Physical Description of The Servo PCBA . .
..... . ... .... .. .. .................. 3-18
Input Control Lines
.. .................. ... .. ............................. 3-18
SECTION IV-TROUBLESHOOTING GUIDE
4.
4.1
4.2
4.3
4.4
4.5
4.6
~ntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-1
Not Ready and/or No Index ................. . ...... ........... ............. 4-2
Will Not Seek or Restore . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Will Not Write . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Will Not Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Front Panel LED Inoperative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
No Track 00 Indication
............ .. ........................... . .. ........ 4-3
SECTION V - REPLACEMENT PROCEDURES
5.
5.1
Introduction ................................................. ... . . . . .... 5-1
Drive Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
ii

Section
Number Title of Section
TABLE OF CONTENTS
SECTION V - REPLACEMENT PROCEDURES
Page
Number
5.2 Logic PCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
5.3 Servo PCBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
5.4 Cone Lever Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5.5 Cone
Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
5.6 Activity
LED Assembly ................................................... 5-12
5.7 Front Panel
............................................................ 5-14
5.8 Guide Rail
... . . ...................................... ....... ... . ....... 5-17
5.9 Index Assembly
....... . ... ... ........................................... 5-19
5.10 Drive Motor Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22
5.11 Track 00 Switch Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
5.12 Write Protect Switch Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-27
5.13 Upper
Arm Assembly (Single-Sided Drives Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-30
5.14 Module Assembly
....................................................... 5-32
5.15 Spindle Asssembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-34
5.16 Latch Plate Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
APPENDIX I- PCB SCHEMATICS AND ASSEMBLY DRAWINGS ..................... 1-1
APPENDIX II -TIMING REQUIREMENTS ........................................... 11-1
APPENDIX Ill- MASTER SPARE PARTS LIST ................................... . . 111-1
iii

FIGURES
Figure
Number Title of Figure
LIST OF ILLUSTRATIONS
Page
Number
SECTION I-INTRODUCTION TO THE TM-100-1 AND-2 DISK DRIVES, 48 TPI
1-1
1-2
1-3
1-4
1-5
1-6
TM-100 Disk Drive Mounting Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
TM-100 Disk Drive Functional Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
FM Recording Magnetization Profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
Write Operation Timing Diagram
.. . ... ... ... ............ .................... 1-1 O
Read Timing Diagram .................................................... 1-11
Logic Printed Circuit Board Assembly ..... ..... ..... . . . . . ... ..... ............ 1-13
SECTION II -MAINTENANCE CHECKS AND ADJUSTMENTS
2-1 Bottom View of The TM-100 Disk Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2-2 Location of
R4 Speed Control Pot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2-3 ISV Pulse Pattern
....................... .... . ...... .. . .... ... .. .. . .... . . 2-3
2-4 Hub Center Line
and Track Locations . .... . . .. .... ................. ... ... .... 2-4
2-5 Cats
Eye Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
2-6 Head Module Retaining
and Cam Screws .... ... . .. . . ... ... .. .. .. . . . . ..... . .. . 2-6
2-7 Track
00 Stop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
2-8 Index-to-Data Pulse . .
... . . .... ...... ... . . .. ........ ..... . ...... ......... 2-8
2-9 Index Sensor's Retaining Screw
and Adjustment ............................... 2-10
2-10 Upper
Arm and Nuts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
2-11
Write Protect Switch Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
SECTION Ill-PRINTED CIRCUIT BOARD OPERATION
3-1 Log ic PCBA . ........................ . . . .......................... . ... .. 3-1
3-2 Interface Configuration ................................................... 3-3
3-3 Select Lines Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
3-4 Drive Motor Enable Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
3-5 Direction
and Step Lines Schematic Diagram . . .. . . .... . ... .. . . ....... .. ..... . . 3-8
3-6 Write Data Circuit Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-1 O
3-7 Write Data Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
3-8 Side Select Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12
3-9 Index Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13
3-1 O Waveform at Test Point 7 (Soft Sectored) . ................... ........... . ..... 3-13
3-11 Track 00 Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14
3-12 Write Protect Schematic Diagram
... .... . .. ........................... . ..... 3-15
3-13 Read Data Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16
3-14 Read Circuit Block Diagr
am . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
3-15 Servo PCBA
........ ..... .. .. .. ...... . . ... . .. . . ... . . . .. ...... ... . .. . ... 3-18
3-16 Servo Board Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19
iv

FIGURES
Figure
Number Title of Figure
LIST OF ILLUSTRATIONS
Page
Number
SECTION V - REPLACEMENT PROCEDURES
5-1 Drive Belt and Pulleys .................................................... 5-2
5-2 Logic PCBA Connectors
and Mounting Screws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
5-3 Servo PCBA Connectors, Mounting Screws,
and Spacers ........................ 5-4
5-4 Cone Lever Assembly Harnessing
and Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
5-5 Cone Lever Assembly Harnessing, Mounting,
and Stepper Motor Cables ............ 5-7
5-6 Cone Lever Assembly Cable Harness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
5- 7 Cone Shaft and E-Ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
5-8 Cone's Component Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-1 0
5-9 Activity LED Assembly Cable Harnessing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
5-10 Activity LED Assembly Retaining Collar
and LED Grommet ............. ... ... .... 5-13
5-11 Front Panel Bushings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
5-12 Activity LED Assembly Retaining Collar
and Grommet . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-15
5-13 Front Panel Mounting Screws
.............................................. 5-15
5-14 Front Panel Bushings
and Locating Tabs ..................................... 5-17
5-15 Index Emitter Sensor Harnessing
and Mounting ................................ 5-19
5-16 Index Detector Sensor Mounting Screw
and Cable .............................. 5-20
5-17 Index Emitter
and Index Detector Sensor Cables and Bundle ............. ......... 5-20
5-18 Drive Motor Assembly Harnessing
and Mounting .......................... . .... 5-22
5-19 Drive Motor Assembly Pulley . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
5-20 Track
00 Switch Assembly Cable Harnessing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
5-21 Track 00 Switch Assembly E-Rings and Adjustment Screw ....................... 5-25
5-22 Track
00 Switch Assembly Mounting Screw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
5-23 Write Protect Switch Assembly
Arm and Adjustment Screw . . . . . . . . . . . . . . . . . . . . . . . 5-27
5-24 Write Protect Switch Assembly Mounting Screw
and Connector P8 . . . . . . . . . . . . . . . . . 5-28
5-25 Write Protect Switch Assembly Cable Harnessing
.............................. 5-28
5-26 Nuts for Upper
Arm and Spring Retainer ...................................... 5-30
5-27 Upper Arm Assembly Parts
................................. ... ............ 5-31
5-28 Felt Pad on Upper Arm ...................................... . ............ 5-31
5-29 Module Assembly Parts ....... . .......... .. ... . ........................... 5-32
5-30 Spindle Assembly Mounting Screw, Washer,
and Pulley ......................... 5-34
5-31 Spindle Assembly Retainer and Hex Head Screws .............................. 5-35
5-32 Latch Plate Assembly Mounting Screws
and Latch Inhibitor . . . . . . . . . . . . . . . . . . . . . . . 5-37
TABLES
Table
Number Title of Table Page
Number
SECTION I- INTRODUCTION TO THE TM-100-1 AND-2 DISK DRIVES
1-1
1-2
1-3
Mechanical
and Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Interface Connector
Pin Assignments, J1 / P1 ........................... . ...... 1-12
Power Connector
Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
V

TABLES
Table
Number Title of Table
LIST OF ILLUSTRATIONS
Page
Number
SECTION Ill -PRINTED CIRCUIT BOARD OPERATION
3-1
3-2
3-3
3-4
Symbols and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Interface Connector Pin Assignments,
J1 / P1 .................................. 3-4
PowerConnector Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Stepper Logic Truth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
vi

SECTION I
INTRODUCTION TO THE TM-100-1 AND -2 DISK DRIVES, 48 TPI
1. INTRODUCTION
This section contains a description of the physical and functional specifications for the TM-100-1 and -2 disk
drives, 48 tracks per inch (TPI), manufactured by Tandon Corporation.
1.1 PURPOSE OF THE DISK DRIVE
The diskdrive is a"mini"diskmemorydesignedfor random accessdataentry, storage, and retrieval applications.
These applications typically are intelligentterminal controllers, microcomputers, word processing systems, data
communications systems, error logging, microprogram loading, and point-of-sale terminals.
The disk drive is capable of recording and reading digital data, using FM, MFM, M2FM or GCR techniques.
1.2 PHYSICAL DESCRIPTION OF THE DISK DRIVE
The disk drive can be mounted
in anyvertical or horizontal plane. However, when mounted horizontally, the logic
circuit board must be up.
The spindle is belt driven by a DC motorwith
an integral tachometer. The servo control circuit, suitably sized pul-
leys, and the tachometer control the speed ofthe spindle. The Read/Write, double-sided head assembly is posi-
tioned by means of a stepper motor, split band, and a suitably sized pulley.
The Read/Write/Erase head assembly is aglass-bondedferrite/ceramicstructure. It has a life in excessof20,000
hours.
For diskette loading, operator access is provided via a slot which is located at the front of the unit.
The electroniccomponents ofthe diskdrive are mounted on two Printed Circuit Board Assemblies (PCBA's), one
of which (logic) is located above the chassis, the other of which (servo) is mounted at the rear of the unit. Power
and interface signals are routed through connectors that plug directly into the logic PCBA.
1.3 FUNCTIONAL DESCRIPTION OF THE DISK DRIVE
The disk drive is fully self-contained. It requires no operator intervention during normal operation. The disk drive
consists of a Spindle Drive system, a Head Positioning system, and a Read/Write/Erase system.
The TM-100-1 is a single-sided disk drive. The TM-100-2 is a double-sided disk drive. The only difference be-
tween the two units is the number of heads in the disk drive. The Logic PCB is identical in both models.
When the front door is opened, access is provided for the insertion of a diskette.The diskette is accurately posi-
tioned by plastic guides and by the front latch inhibitor. The in /out location is ensured by the backstop.
Closing the front dooractivates the cone/clamp system, resulting in centering of the diskette and clamping of the
diskette to the drive hub. The drive hub is driven at a constant speed of 300 rpm by a servo-controlled DC motor.
The magnetic head is loaded into contact with the recording medium whenever the front door is closed.
1-1

The magnetichead is positioned overthe desired trackbymeans ofa steppermotor/band assemblyand its asso-
ciated electronics. This positioner employs a one-step rotation to cause a one-track linear movement. When a
write-protected diskette is inserted into the disk drive, the Write Protect sensor disables the write electronics of
the diskdrive, and a Write Protect output signal is applied to the interface.
When performing a write operation, a 0.33 mm (0.013-inch) (nominal) datatrack is recorded. Then, this track is
tunnel erased to 0.30 (0.012 inch) (nominal).
Data recovery electronics include a low-level read amplifier, adifferentiator, azero crossing detector, and digitiz-
ing circuits.
No datadecoding ability is provided in the basic disk drive.
The disk drive is also supplied with the following sensor systems:
1. A Track00 switch thatsenseswhen the Head/Carriageassemblyis positioned atTrack00.
2. The Index sensor, which consists of a LED light source and phototransistor, is positioned
such that a digital signal is generated when
an index hole is detected. The Indexsensoris a
high resolution device that can distinguish holes placed close together, i.e., index sector
holes
in a hard-sectored diskette.
3. The Write Protect sensordisables the diskdrive write electronics whenever a write-protect
tab is applied to the diskette (see Section 1.13).
1.4 DISKETTES
The disk drive uses a standard 133.4 mm (5.25 inch) diskette. Diskettes are available with a single index hole or
with index and sector holes.
Single index hole diskettes are used when sector information is pre-recorded on the diskette. Multiple index hole
diskettes provide sector pulses by means of the Index sensor and electronics.
1.5 MECHANICAL AND ELECTRICAL SPECIFICATIONS
The mechanical and electrical specifications of the disk drive are listed
in Table 1-1.
1.6 INTERFACE CIRCUIT SPECIFICATIONS
The interface circuits are designed so that a disconnected wire results in a false signal.
Levels:
True = +0.4 V (maximum)
False = +2.4 V (minimum)
1.7 UNCRATING THE DISK DRIVE
The disk drive is shipped in a protective container which, when bulk packaged, minimizes the possibilityofdam-
age during shipment. The following procedure is the recommended method for uncrating the disk drive.
1. Place the shipping container on a flat work surface.
1-2

TABLE 1-1
MECHANICAL AND ELECTRICAL SPECIFICATIONS
Media
Dimensions
Height
Width
Length
Weight
Temperature (Exclusiveof Media)
Operating
Nonoperating
Relative Humidity(Exclusive of Media)
Operating
Nonoperating
Head Settling Time
Error Rates (Maximum)
Soft Read
Hard Read
Head Life
MediaLife
DiskSpeed
lnstantaneou~ Speed Variation
Start/StopTime
Transfer Rate
Bits Per Disk (Unformatted)
Recording Modes (Typical)
Power
1-3
Industry-Standard5.25"diskette
85.85 mm (3.38 inches)
149.1 mm (5.87 inches)
203.2 mm (8.00 inches)
1.45 Kg (3.2 pounds)
10°Cto 44°C (50°Fto
11 2°F)
-40°C to
71 °C (-40°Fto 160°F)
20%to 80% (Noncondensing)
5%to 95% (Noncondensing)
15 msec (LastTrackAddressed)
1per 109 bits (Recoverable)
1per 10
12
bits (Nonrecoverable)
20,000 Hours (Normal Use)
3.6x 106 Passes PerTrack
300 rpm ± 1.5%(Long Term)
±3%
250/150 msec (Maximum)
FM: 125,000BPS
MFM: 250,000 BPS
2 Million (FM)
FM ,MFM, MMFM
+ 12VDC ±0.6VDC @ 900mA
(Average Maximum)
+5 VDC ± 0.25 VDC @600 mA
(Average Maximum) with 100 mv
P/P Ripple

2. Remove the upper half of the inner container.
3. Remove the disk drive from the lower half of the inner container.
4. Check the model number and top assembly description against the packing slip.
5. Examine the contents of the shipping container for possible damage.
6. Notify the carrier immediately if any damage is noted.
1.8 PHYSICAL CHECKOUT
OF THE DISK DRIVE
Before applying powerto the diskdrive, the following inspection procedure should be performed:
1. Remove the plastic bag.
2. Remove the cable harness from the door latch of
+he disk drive.
3. Check that the front latch opens and closes. Note that when the door is opened, the head
arm raises.
4. Ensure that the front panel is secure.
5. Manually rotate the drive hub. The drive hub should rotate freely.
6. Check that the PCBA's are secure.
7. Check that the connectors are firmly seated.
8. Check for debris or foreign material between the heads.
9. Notify the carrier immediately if any damage is noted.
1.9 INTERFACE CONNECTIONS
Signal connections forthe diskdrive are madevia a user-supplied 34-pin, flat ribbon connector(3M Part Number
3463-0001 or equivalent). This connector mates directly with the PCBA connector at the rear of the disk drive.
The DC power connector is a four-pin connector (Amp Mate-N-Lok Part Number1-480424-0), which mates with
the connector on the logic PCBA at the top rear of the disk drive.
The signal connector harness should be ofthe flat ribbon ortwisted pairtype, have a maximum length often (10)
feet, and have a 22-to-24 gauge conductor compatible with the connector that is to be used.
Power connections should be made with 18-AWG cable (minimum).
In addition, the PCBA-mounted, DC power
connector is keyed.
1.1 O CHASSIS GROUND
To ensure proper operation of the diskdrive, the chassis should beconnected to earth ground. A 3/16-inch male
QC lug, located at the rear of the chassis, is provided to facilitate this connection.
1-4

1.10.1 Isolated Ground
The power return of the disk drive is connected to the drive chassis. If a particular application does not require
this, the mounting screw nearthe middle ofthe servo PCB may be replaced with a nylon screw. This isolatesthe
power return from the chassis ground.
1.11 MOUNTING THE DISK DRIVE
The disk drive has been designed such that it can be mounted
in any plane, i.e.: upright, horizontal, or vertical.
The only restriction is that the logic PCBAside ofthe chassis must be uppermost when the diskdrive is mounted
horizontally. Eight (8) 6-32 tapped holes are provided for mounting: two (2)
on each side and four (4) on the bot-
tom ofthe housing (see Figure 1-1).
BOTTOM
MOUNTING ;---......__
HOLES (2) \ --....._ +
---1
BOTTOM VIEW
FOUR (4) MOUNTING HOLES
ON UNIT FARSIDE (BOTTOM).
No. 6-32 UNC-28 x .31 DP.
.06~ -
,L,' ...
I . L .J
BOTTOM
MOUNTING
HOLES (2)
•:
1. 25 -- ► 1
,-- .86
.. J_j SERVO P.C.B.A.
+~
SIDE
MOUNTING
HOLE
1
3 .1 2
I
+---
l-3 . 38-
SIDE
MOUNTING
HOLE
SIDE VIEW
Figure 1-1
TM-100 Disk Drive Mounting Configuration
1.11.1 Hardware
The disk drive is manufactured with certain cricital internal alignments that must be maintained. Hence, it is im-
portant that the mounting hardware does not introduce significant stress on the disk drive.
1-5

Any mounting scheme in which the disk drive is part ofthe structural integrity ofthe enclosure maycause equip-
ment operating problems and should be avoided.
Mounting schemes should allow for adjustable brackets or incorporate resilient members to accommodate
tolerances.
1.11.2 Dust Cover
The design of an enclosure should incorporate a means to preventcontamination from loose
items- e.g., dust,
lint, paper chad -since the disk drive does not have a dust cover.
1.11.3 Cooling System Requirements
Heat dissipation from a single disk drive is normally 15 watts
(51 Btu/Hr.) under high line conditions. When the
diskdrive
is mounted so thatthe components have accessto thefree flow of air, normal convection cooling allows
operation over the specified temperature range.
When the diskdrive is mounted
in aconfined environment, airflow must be provided tomaintain specified airtem-
peratures
in the vicinity of the motors, the PCBA's, and the diskette.
1.12 DISKETTE CARE, HANDLING, AND STORAGE
It is importantthatthe diskette be cared for, handled, and stored properlyso thatthe integrityofthe recorded data
is maintained. Adamagedorcontaminated diskettecan impairorpreventrecoveryofdata, and can result
in dam-
age to the Read/Write heads
of the disk drive.
The following list contains information on how the diskette can optimally be cared for, handled, and stored.
1. Keep the diskette away from magnetic fields.
2. Do not touch the precision surface of the diskette with fingers.
3. Insert the diskette carefully into the disk drive until the backstop is encountered.
4. Do not bend orfold the diskette.
5. Put the diskette into its jacket when it is not in use.
6. Store the diskette at temperatures between 10°c and 52°C or 50°F and 125°F.
1.13 WRITE PROTECT
The diskdrive
is equipped with a Write Protect Switch Assembly. This sensoroperates in conjunction with a dis-
kette that has a slot cut
in the protective jacket.
When the slot
is covered with a self-adhesive tab, the diskette is write protected. The slot must be uncovered to
write on the diskette.
1.14 OPERATION OF THE DISK DRIVE
The diskdrive consists ofthe mechanical and electrical components necessaryto record and to read digital data
on a diskette. User-provided DC power at +12 V and +5 V
is required for operation of the disk drive.
1-6

1.15 ORGANIZATION OF THE DISK DRIVE
All electrical subassemblies
in the disk drive are constructed with leads that terminate in 4- to 5-pin connectors,
enabling the individual assemblies to be removed.
The magnetic heads are connected to the PCBA via cables that terminate
in 5-pin female connectors and their
associated male sockets, which are located in close proximity to the Read/Write data electronics.
Interface signals and power are ;Jrovided via connectors at the rear of the disk drive.
1.16 COMPONENTS
OF THE DISK DRIVE
The disk drive consists of seven (7) functional groups:
1. Index Pulse Shaper
2. Write Protect Sensor .
3. Track 00 Sensor
4. Spindle Drive Control
5. Carriage Position Control
6. Write/Erase Control
7. Read Amplifier and Digitizer
Figure 1-2 is a functional block diagram of the diskdrive. It should be referred to
in conjunction with the following
sections. The data
in the ensuing figures is primarily represented in simplified form.
1.16.1 Index Pulse
An index pulse is provided to the usersystem via the Index Pulse interface line.The index circuitry consists of an
Index LED, an Index Photo Transistor,and a Pulse Shaping Network.As the index hole
in thedisk passes the In-
dex LED/Photo Transistor combination, light from the LED strikes the Index Photo Transistor, causing it to con-
duct. The signal from the Index PhotoTransistoris passed to the Pulse Shaping Network, which producesa pulse
for each hole detected. This pulse is presented to the user on the Index Pulse Interface line.
1.16.2 Write Protect
A Write Protect signal is provided to the user's system via the Write Protect interface line. The Write Protect cir-
cuitry consists of a Write Protect sensor and circuitry that routes the signal that is produced.
When a write protecteddiskette is inserted in thediskdrive,the sensoris activated andthe logicdisablesthewrite
electronics and supplies the status signal to the interface.
1.16.3 Track 00 Switch
The level on the Track 00 interface line is a function of the position of the magnetic head assembly. When the
head is positioned atTrack 00 and the stepper motor is atthe home position, a true (low) level signal is generated
at the interface.
1.16.4 Spindle Drive System
The Spindle Drive system consists of a spindle assembly driven through a drive belt by a DC motor/tachometer
combination.
1-7

The servo electronics required for speed control are associated with the spindle drive motor.
The control circuitry also includes a current limiter and interface control line. When the Drive Motor Enable inter-
face line is true, the drive motor is allowed to come up to speed. When the current through the drive motor ex-
ceeds 1.3 ampere, the current limit circuitry disables the motor drive.
#'INDEX
.. EMITTER
O.C. STEPPER MOTO
INDEX
/~ • / Ce1!
PULSE PULSE SHAPING
~:., r-c,-"
NETWORK
A
I BAND DRIVE AND
he: HEAD ASSEMBLY
WRITE
~
PROTECT
WRITE
bETECTOA D. C. DRIVE
PROTECT
~~
SWITCH
TRACK
~
00
TRACK e8
SWITCH
..
DRIVE
MOTOR
ENABLE
SPINDLE DRIVE
-
INTERFACE
CONTROL
CONTROL
•
DIRECTION POSITION
ER
STEP
CONTROL
t WAITE
BUSY
WRITE
WRITE /ERASE
DATA
CURRENT SOURCE
ANO WAVEFORM
GENERATOR
WAITE ENABLE
SIDE SELECT
READ DATA
READ AMPLIFIER
AND DIGITIZER
Figure 1-2
TM-100 Disk Drive Functional Block Diagram
1.16.5 Positioner Control
The Head Positioning system utilizes afour-phase steppermotordrive,which changes one phase foreach track
advancement ofthe Read/Write carriage. In addition to the logic necessaryfor motion control, a gate is provided
which inhibits positioner motion during a write operation.
1.16.6 Data Electronics
Information can be recorded on thediskettebyusing adouble-frequencycode. Figure 1-3illustratesthe magneti-
zation profiles in each bit cell for the number sequence shown for FM recording.
The erase gaps provide a guard band on either side of the recorded track. This provides flexibility in track posi-
tioning.
All signals required to control the data electronics are provided bythe user system and are shown
in the TM-100
diskdrive functional block diagram (see Figure 1-2). These control signals are:
1. Select
2. Write Enable
1-8

3. Write Data
4. Side Select
The Read Data composite signal is sent to the user system via the interface.
-H BIT C ELL
~
I I 0 0
I I
BIT PATTERN i I
I I
NWAITEDATA I I i
I I I I : :
I I I I I I I I I I I I I
I I I I I I I I I I I I I :
M n 1 m n , v-r, p
MAGNETIZATION ' ~ I
_], u~~I I I : ~~c
I I I 1 1 : : : : i I : I I :
1 I I I I I I I I I I I I I I
MAGNETIC ELEMENTS . ;::;.l<::::),~~-Aff
N,~00Llis0s€NSDGJ
I I I . I I I I I I I I I I '
I I I I I ·I I i I I : I I I :
I I I I I I I I I I I I I I I
I I I I I I I I I I I I I I I
Figure 1-3
FM Recording Magnetization Profiles
1.16.6.1 Data Recording
The write electronics consist of a Write Current Source, a Write Waveform Generator, an Erase Current Source,
the Trim Erase Control Logic, and the Head Select Logic (see Figure 1-2).
The read/write winding on the magnetic head is center-tapped. During a write operation, current from the Write
Current Source flows in alternate halves of the winding, under control of the Write Waveform Generator.
The conditions required for recording, i.e., unit ready, must be established by the user system, as follows:
1. Drive speed stabilization occurs 250 msec after the drive motor is started.
2. Subsequent to any step operation, the positioner must be allowed to settle. This requires
20 msec after the last step pulse is initiated, i.e., 5 msec for the step motion and 15 msec
for settling.
3. The foregoing operations can be overlapped, if required.
Figure 1-4 illustratesthe timing diagram for a write operation.Att= 0, when the unitis ready, the Write Enable in-
terface line goes true. This enables the Write Current Source.
The Trim Erase control goestrue 390 msec afterthe Write Enable interface line since thetrim erasegaps are
be-
hind the read/write gap. It should be noted that this value is optimized between the requirements at Track 00 and
at Track 39, so thatthe effect of the trim erase gaps on previous information is minimized.
Figure 1-4 shows the information on the Write Data interface line and the outputofthe Write Waveform Genera-
tor, which toggles on the leading edge of every Write Data pulse.
Notethat a minimum of 4 usecand a maximum of8 usecbetween Write Enablegoing true and thefirstWrite Data
pulse is only required if faithful reproduction of the first Write Data Transition is significant.
At the end of recording, at least one additional pulse on the Write Data line must be inserted afterthe last signifi-
cant Write Data pulse to avoid excessive peak shift effects.
1-9

WAITE ENABLE
TRIM ERASE
INTERNAL
WAITE BUSY
NWAITEDATA
WAITE
WAVEFORM
GENERATOR
NOTE1
r
I
I
390 ~ secs- L+-- 800 ~
I
I W I usec s I
I
~ I " r
_____ 1 __ .., _____________ i_ ... ~
S !
NOTE 2
I
I
I
I
WRITE CURRENT~k----N,
I I I
- --- I --- - ·- 7~-- ....-
NOTE~
NOTES, 1. t • 0 • 250 MILLISECONDS AFTER DRIVE MOTOR
STARTS
OR 20 MILLISECONDS AFTER LAST STEP
PULSE, 'WHICHEVER IS THE LATEST TIME
Figure 1-4
1 _---r I
I I
I I
I I
2. UNSYNCHRONIZED
3. 8.5 MA PEAK TO PEAK
4. 4 u SECONDS MINIMUM, 8 u SECONDS MA XIMUM
Write Operation Timing Diagram
The duration ofa write operation is fromthetruegoing edgeof Write Enabletothe false going edgeofTrim Erase.
This is indicated by the internal Write Busy waveform shown (see Figure 1-4).
The Read electronics consist of:
1. Read Switch/Side Select
2. Read Amplifier
3. Filter
4. Differentiator
5. Comparator and Digitizer
The Read switch is used to isolate the Read Amplifier from the voltage excursion acrossthe magnetic head dur-
ing a Write operation. The side select is used to enable one of the Read/Write/Erase heads.
The disk drive must be in a ready condition before reading can begin. As with the data recording operation, this
ready condition must be established
by the user system. In addition tothe requirements established in this sec-
tion, a 100usec delay must existfrom the trailing edgeofthe Trim Erase signal to allowthe Read Amplifierto set-
tle after the transient caused by the Read switch returning to the Read mode.
The outputsignal from the Read/Write head is amplified bya Read Amplifier and filtered bya linearphasefilterto ·
remove noise (see Figure 1-5).The linear output from the filter is passed tothe Differentiator, which generates a
waveform whose zero crossovers correspond tothe peaks ofthe Read signal. Then,thissignal is fed tothe Com-
parator and the Digitizer circuitry.
1-10

LINEAR OUTPUT FROM FILTER
OUTPUT FROM
DIFFERENTIATOR
READ DATA INTERFACE
NOTES: t z O z250 MILLISECONDS AFTER DRIVE MOTOR STARTS, t
OR 20 MILLISECONDS AFTER STEP COMMAND, OR t z O
100 u SECONDS AFTER TERMINATION OF WRITE
BUSY, WHICHEVER IS THE LATEST TIME
Figure 1-5
Read Timing Diagram
The Comparatorand the Digitizercircuitry generate a 1usec Read Datapulse, corresponding to each peakofthe
Read signal. Then, the Composite Read Data signal is sent to the user system via the Read Data interface line.
1.17 INTERFACEELECTRONICS
All interface signals are TTL-compatible. Logic true (low) is +0.4V (maximum); logic false (high) is +2.4V (mini-
mum). The maximum interface cable length is ten (10) feet.
It is recommendedthatthe interfacecable be flat ribbon cable, having a characteristicimpedenceof100ohms,or
equivalent twisted pairs.
1.17.1 Interface Connector Pin Assignments,
J1 / P1
The interface connector pin assignments, J1 /P1, are listed in Table 1-2.
1.17.2 Power Connector Pin Assignments
The power connector pin assignments are listed
in Table 1-3.
1.18
1.18.1
OPTION SELECT
Input Line Terminations
The disk drive has the capability of terminating the following input lines:
1. Motor On
2. Direction Select
3. Step
4. Write Data
1-11

TABLE 1-2
INTERFACE CONNECTOR PIN ASSIGNMENTS,
J1 / P1
CONTROLLER-TO-DISKDRIVE
Ground Signal Mnemonic Description
1 2 ConnectorClamp . -
3 4 Spare
5 6
Select3
(NDS3)
""
9 10 Select 0 (NDS0) /
11
12 Select 1 (NDS1)
13 14 Select2
(NDS2)
15 16 Drive MotorEnable
(NMOTORON)
17 18 Direction (DIR)
19 20 Step
(N STEP)
21 22 Write Data (N WRITE DATA)
23 24 WriteGate
(N WRITE ENABLE)
31
32 Side Select
(N SIDE SELECT)
33 34 ConnectorClamp
DISK DRIVE-TO-CONTROLLER
Ground Signal Mnemonic Description
7 8 Index (N INDEX / SECTOR)
25 26 Track 00
(NTRK00)
27 28 Write Protect
(N WRITE PROTECT)
29 30 Read Data
(N READ DAT A)
1-12