Control Data Corporation BR8 SERIES Owner's manual

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~ c:\ CONTI\.OL DATA
\!:I r:!I CORPOR{\TION
CONTROL DATA ®
FLEXIBLE DISK DRIVE
GENERAL DESCRIPTION
OPERATION
INSTALLATION AND CHECKOUT
THEORY OF OPERATION
DIAGRAMS
MAINTENANCE
MAINTENANCE AIDS
PARTS DATA
WIRE LISTS
MAGNETIC PE~PHER(\LS INC.
I';:ll::\ a subsidiary of
\:=J r:J CONTRPl DATA CORfORATION
HARDWARE MAINTENANCE MANUAL
77834769

f\~·es~
R E V
R
TABLE OF CONTENTS
E
DATE
SHEETS AFFECTED
V
W 79 PF
Mav23
ii
Y
ii,
iv
01978, 1979
Magnetic Peripherals Inc.
ii
I a I 0
1 2 3
L A A
L A A
~
- FDD FSM
N R E C 0 R D
MANUAL/SECTION REVISION STATUS
CHANGE
4 5 6 7
E U W A
E Y Y A
8 9 10
11
12
AUTHORITY
K A
PI 21165
K A
PL 21174
Address comments concerning this manual to:
Technical Publications
Magnetic Peripherals Inc.
4000 Northwest 39th Expressway
Oklahoma City, Oklahoma 73112
or use the enclosed user comment sheet.
Printed in the United States of America
All Rights Reserved
77834769-Y
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PREFACE
This manual provides the information needed to install, operate and maintain the
Control Data Corporation Flexible Disk Drive (FDD) and is intended to support
customer engineers who requii.~e detailed information about the Flexible Disk Drive's
operation.
The total content of the manual is comprised of two publications, each having a unique
pUblication number, and is contained in one volume. The Manual's publication number
(77834769) is that of the front matter, sections one through seven, and section
nine. This number should be used when making reference to the Flexible Disk Drive
Hardware Reference Maintenance Manual. Section VIII, Parts Data, is identified by the
unique pUblication number 77834771.
This manual applies to several models of the FDD. A configurator sheet is provided
on the following page which describes each FDD configuration that this manual will
support. Refer to the eqUipment nameplate located on the right hand sIde of the unit
(as viewed from the front) to determine the appropriate Top Mechanical Assembly
(TMA) and Model numbers. Then use the Configurator sheet as a starting point to
establish the maintenance level for the device.
77834769 -D
'iii

FLEXIBLE DISK DRIVE CONFIGURATOR SHEET
•
P V
0 D
W C
E
R V
R A
C
E
MAGNETIC PEI\IPHER..ALS INC
CS~~~~~~~rV~\A l()~'OR ... AIIU~
+5 & +24 AT J7
+5 & +24 AT I/O Jl
240, lit
220, 1 It
120
10'
10
100
10'
WRITE SPLICE ADJ. (See Table 6-2)
CIRCUIT BD. CONFIG. (See Table_5_-1t
o"AISY-CHAIN
INTERFACE
- ----
STANDARD INTERFACE
- - ----
--
TMA NO.
MODEL NO
75744001
BR803A
X 506
002
BR803B
X 506
003
BR803C
X 506
004
BR803D
X 506
005
BR803E
X 502
006
BR803F
X 502
007
BR803G
X
502
008
BR803H
X 502
009
010
011
012
013
BR803N
X 503
014
BR803P
X 503
015 BR803R
X 503
016
"BR803S
X 503
017
BR803J X 502
018
BR803K
X
502
019
BR803L
X
513
020
BR803M
X
513
021
BR8A3C
X 502
022
BR8A3D
X 502
023 BR8A3E
X 502
024
BR8A3F
X 502
025
BR8A2A X 505
026 BR803T
X 503
027
028
BR8A3A
X 501
029
0))
BR8A2B
X 505
031 BR8A2C
X 505
032
BR8A2D
X
505
033
BR8A2E
X 505
034
BR8A2F
X 506
035 BR8A2G 510
036 BR8A2H
X 506
037
BR8A2J
X 505
038 BR8A2K
X
509
039
BR8A2L
X
507
iv
--
-- --
------
----
--
-- --
----
-- -- --
- ---
-- ----
-- -- -- ----
603
X
603
X
603 X
603
X
603
X
603
X
603 X
603 X
602
X
602
X
602
X
602 X
603
603
603
. X
603
X
603
X
603
X
603 X
603 X
603
X
603
603
X
603
X
603 X
603
603
X
603
X
603
X
603 X
603 X
603
X
603
X
--
-- --
--
-- --
- - --
--
- -
--
--
--- - --
------
---- --
--
----
- - -- --TMA
NO.
X 75744041
X 042
X 043
X 044
X 045
X 046
X 047
X 048
049
050
051
052
X 053
X 054
X
055
X
056
X X 057
X X
058
X 059
X
060
X
061
X
062
X 063
X 064
X 065
X X
066
067
X
068
0,S9
X 070
X 071
X X
072
X 073
X 074
075
X
076
X 077
X 078
X 079
TOP MECHANICAL ASSEMBLY NO. (TMA)
MODEL NO. (BR8XXX)
AC POWER REQUIRED (ON UNITS LABELED 50/60 Hz·
CHECK CONFIGURATION OF PULLEY FOR
FREQUENCY) •
EQUIPMENT
STATUS NUMBER
UNIT SERIAL NO.
MODEL NO
BR8A2N
X
505
603
BR8ASA
X 508
603
BR8ASB
X 508
603
BR8A2W
X 501
603
BR8A2Y X
501
603
BR8A6B X
506
603
BR803U X
506
603
BR8A2S
X 510
603
BR8A2T
X
510
603
BR8A2U
X
512
603
BR8A2V
X
507
603
BR8A2Z
X
505
603
BR8A3G X 504
601
BR8A3H X 504
601
X 509 603
BR8ASC
X 508 603
BR8ASD
X
511
603
X
X X
X X
X X
X X
X X
X
X
X X
X
X X
X X
X
77834769-Y
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X
X
X
X
X
X
X
X
X
X
X
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TABLE OF CONTENTS
SECTION
PAGE
I GENERAL DESCRIPTION
1. 1 INTRODUCTION •• • • • • • • • • • • • • • • • • • • • • • • • • •• 1-1
1. 2 PURPOSE AND USE OF EQUIPMENT •••••••• • • • • • • 1-1
1.3 PRODUCT DESCRIPTION ••••••••••••••••••••••• 1-1
1.3. 1 Physical Description ••••••••••••••••••• 1-2
1. 3. 2 Electrical Description •••••••••••••••••• 1-2
1. 3. 3 Performance Characteristics ••••••••••••• 1-2
II OPERATION
2.1
2.2
2.3
2.4
INTRODUCTION •••••••••••••••••••••••••••••
OPERATING INSTRUCTIONS ••••••••••••••••••••
2. 2. 1 Flexible Diskette Loading ••••••••••••••••
2.2. 2 Flexible Diskette Removal •••••••••••••••
ERROR RECOVERY ••••••••• • • • • • • • • • • • • • • • • • •
2. 3. 1 Seek Error • • • • • • • • •••••••• • • • • • • • • • •
2. 3. 2 Write' Error •••••••••••••••••••••••• • •
2. 3. 3 Read Error • • • • • • • • • • • • • • • • • • • • • • • • • •
DISKETTE HANDLING RECOMMENDATIONS ••••••••••
2-1
2-1
2-1
2-1
2-1
2-1
2-1 .
2-2
2-2
III INSTALLATION AND CHECKOUT
3.1
3.2
3.3
3.4
3.5
3.6
INTRODUCTION •••••••••••••••••••••••••••••
UNPACKING ...............................
INST ALLA TI ON •••••••••••••••••••••••••••••
CABLING AND CONNECTIONS •••••••••••••••••••
3.4. 1 Input/ Output Cable •••••••••••••••••••••
3. 4. 2 DC Power Connection • • • ••••••••••••••••
3.4. 3 AC Power Connection •••••••••••••••••••
ENVIRONMENT •••••••••••••••••••••••••••••
INITIAL CHECKOUT ••••••••••• • ••• • • • • • • • • • • •
3.6.1
Operating Frequency. • • • • • • • • • • • • • • • • • • •
3-1
3-1
3-1
3-1
3-1
3-2
3-2
3-2
3-2
3-3
JV THEORY OF OPERATION
4. 1 INTRODUCTION. • • • • • • • • • • • • • • • • • • • • • • • • • • •• 4-1
4.2 GENERA L DESCRIPTION • • • • • • • • • • • • • • • • • • • • • •• 4-1
4.3 FUNCTIONAL DESCRIPTION •••••••••••••••••••• 4-3
4.3. 1 Control Logic • • • • • • • • • • • • • • • • • • • • • • •• 4-3
4.3.2 Write and Fault Logic. • • • • • • • • • • • • • • • • •• 4-6
4.3.3 Read Logic • • • • • • • • • • • • • • • • • • • • • • • • •• 4-6
4.3.4 Disk Drive • • • • • • • • • • • • • • • • • • • • • • • • •• 4-7
4.3.5 Read/Write Head ••••••••••• I •••• • • • • • •• 4-7
77834769-A
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SECTION
PAGE
4.4 CONTROL AND DATA LINE CHARACTER1S.TICS • • • • • • •• 4-7
4.4.1 Logic Levels ••••••••••••••••••••••••• 4-7
4.4.2 Transmitter Characteristics ••••••••••••••• 4-7
4.4.3 Line Receiver Characteristics ••••••••••••• 4-7
4.4.4 Control and Data Line Functions. • • • • • • • • • • •• 4-8
V DIAGRAMS
5.1 INTRODUCTION. • • • • • • • • • • • • • • • • • • • • • • • • • • • •• 5-1
VI MAINTENANCE
vi
6.1
6.2
6.3
6.4
6.5
6.6
6.7
INTRODUCTION ..............................
MAINTENANCE TOOLS •••••••••••••••••••••••••
PREVENTIVE MAINTENANCE.' ••••.••••••••••••••••
HEAD CLEANING •••••••••••••••••••••••••••••
TROUBLESHOOTING •••••••••••••••••••••••••••
6. 5. 1 DC Voltage and Signal Check • • • • • • • • • • • • • • •
6.5.2 Diskette Not Rotating •••••• ' •••••••••••••
6• 5. 3 Ready Signal Mis s ing •••••••••••••••••••
6.5.4 Drive Not Responding to Commands ••••••••••
6.5.5 Index Pulse Missing •••••••••••••••••••••
6. 5. 6 Head Not Loading ••••••••••••••••••••••
6. 5. 7 Read/Write. Head not Stepping ••••••••••••
6.5. 8 NO ,Track "00" Indicator ••••••••••••••••
6.5.9 Read Errors ••••••••••••••••••••••••••
6.5.10 Write Errors ••••••.•••••••••••••••••••
6.5.11 Write Protect Inoperative •••••••••••••.•••
ADJUSTMENT PROCEDURES •••••• ••••••••••••••
6.6.1 Carriage-Stop Adjustment •••••••••••• ' ••••
6.6.2 Burst to .Index Check and Adjustment ••••••••••
6.6.3 Actuator Alignment (Diskette) ••••••••••••••
6.6.4 Push Rod Travel Adjustment. •••••••••••••••
6.6.5 Door Interlock Switch Adjustment. ' •••••••••••
6.6.6 Disk Load Bail Adjustment ••••••••••••••••
6.6. 7 Spindle and Cone Adjustment •••••••••••••
6.6.8 Write Protect Assembly Adjustment ••••••••••
6.6. 9 Track "00" Switch Adjustment ••••••••••••••
REMOVAL AND REPLACEMENT PROCEDURES ••••• ' •••
6. 7. 1 Printed Circuit Board (PWA) •••••••••••••••
6.7.2 Actuator Assembly •••••••••••••••••••••
6. 7.3 Drive Motor Assembly • • • • • • • • • • • • • • • • • • •
6. 7.4 Head Load Pad Replacement •••••••••••••••
6. 7.5 Solenoid Replacement and Tang Adjustment •••••
6. 7.6 Carriage arid/or Stepper Motor Replacement •••••
6-1
6-1
6-1
6-1
6-2
6-2
6-5
6-6
6-7
6-8
6-9
6.-10
6-12
6-13
6-15
6-17
6-18
6-18
6-19.2
6-21
6-22
6-23
6-24
6-25
6-26
6-26
6-27
6-27
6-27
6-29
6-29
6-29
6-31
77834769-,H

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SECTION .
PAGE
6. 8 FREQUENY CONVERSION ••••••••••••••••••••••• 6-31
6.8.1 Operating Frequencies Conversion Procedure. • •• 6-31
VII MAINTENANCE AIDS
7.1 INTRODUCTION •••••••••••••••••••••••••••••• 7-1
7.2 PHYSICAL DESCRIPTION (Logic) •••••••••••••••••• 7-1
7.3 USE OF RELATIVE LEVEL INDICATORS. • • • • • • • • • • •• 7-1
7.4 INTEGRA TED CIRCUITS •••••••••••••••••••••••• 7-1·
VIII PARTS DA TA
8.1
8.2
8.3
8.4
8.5
8.6
INTRODUCTION ..............................
ILLUSTRATIONS ••••••••••••••••• " •••••••••••••
PARTS LISTS ••••••••••••••••••••••••••••••••
TOP MECHANICAL AND ASSEMBLY LOCATOR •••••••••
8.4.1 Top Mechanical Assembly (TMA) •••••••••••••
REPLACEMENT PARTS •••••••• ' •••••••••••••••••
PARTS LIST INSTRUCTIONS ••••••••••••••••••••••
8.6. 1 lllustration Parts Lists •••••••••••••••••••
8.6.2 Top-Down Assembly/Component Parts List •••••
8.6.3 Cross Reference Index •••••••••••• , ••••••
8. 6•4 Sheet Number Referencing ••••••••••••••••
IX WillE LISTS
8-1
8-1
8-1
8-1
8-1
8-1
8-10
8-10
8-10
8-10
8-10
9. 1 INTRODUCTION. • • • • • • • • • • • • • • • • • • • • • • • • • • • •• 9-1
9.2 UPPER HARNESS ASSEMBLIES. • • • • • • • • • • • • • • • • • •• 9-1
9.3 LOWER HARNESS ASSEMBLY •••••••• '. • • • • • • • • • •• 9-1
9.4 STEPPER MOTOR •••••••••••••••••••••••••••• 9-1
9.5 WRITE PROTECT • • • • • • • • • • • • • • • • • • • • • • • • • • • •• 9-1
77834769-A
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LIST OF ILLUSTRATIONS
C~
FIGURE,
TITLE
PAGE
2-1
Diskette Installation
2-2
3-1
AC Cable Assembly
3-3
4-1 Functional Block Diagram
4-5
5-1 Timing
5-2
5-2
Schematics
5-4
5-3
Assembly and Parts List
5-10
6-1
-Head Load and Door Interlock Switch
6-3
6-2 Differential Read Signal for Entire Track
6-4
6-3 Differential Read Signal for Portion of
Outer Track 6-4
6-4
Write Data, Write F/F Output, and Head Write
Voltage for Outer Track 6-4
6-5 Base and Chassis Support Assembly
6-19
6-6 Carriage-Stop Adjustment 6-19.1
6-6a
Plastic Carriage-Stop and Stop-Gauge Assemblies
6-19.1
6-6b
Metal Carriage-Stop Assembly 6-19.1
6-7
Write Splice Bit to Index Timing 6-20
C~~
6-8 Head Alignment Amplitude 6-22
6-9 Chassis Base Assembly 6-23
6-10
Disk Load Solenoid 6-24
6-11 Spindle and Cone 6-25
6:"'12
Base Casting Assembly
6-28
6-13
Head Load Pad Replacement Illustration
6-30
6-14 Solenoid Adjustment 6-31
6-15
Drive Pulley Reversal 6-32
7-1
Inversion Conventions
7-1
7-2
Integrated Circuit 7-2
7-3
Schematic Symbols 7-2
LIST OF TABLES
TABLE
TITLE
PAGE
4-1 Phase Sequence of Stepper Motor 4-3
4-2 Input/ Output Lines
4-8
5-1
PWA Configurator 5-1
6-1
Flowchart Reference
6-2
('
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GENERAL DESCRIPTION
1.1 INTRODUCTION
The Flexible Disk Drive (FDD) is a compact, portable, random access, data storage
device that interfaces with a central processor via a control unit. Input/Output
data and control signals are transmitted by means of an r/o cable.
1.2 PURPOSE AND USE OF EQUIPMENT
Data, in the form of magnetized bits, is written on, or read from the tracks of a rotating
diskette. The FDD uses a single, flexible, removable diskette (one recording surface)
enclosed in a sealed jacket. The unit is capable of hard-sector or soft-sector (missing
clock) format operation, but the missing clock must be recovered externally (from the
FDD).
1.3 PRODUCT DESCRI PTI ON
The major FDD components are the spindle, disk drive motor, read/write head,
stepping motor, track indexing device, and printed circuit board.
The options include Write Protect, Data/Clock Separation, Power Reduction, Sector
Separation, Unit Select, Ready, Door Unlock, Write Fault, and Hour Meter.
All FDD components are mounted on a base assembly. The front panel has a spring
loaded door through which the'diskette is installed. The door is mechanically linked
to the disk loading mechanism and the head load interlock switch; therefore, when the
door is closed the Read/Write head may be loaded on the diskette in preparation for the
transfer of data.
Standard Models Versus Daisy-Chain Models - Throughout this manual certain features
and operation of the Flexible Disk Drive are described in terms of the manner in which
the FDD is designed to be connected to its controller, either standard or daisy chain.
Standard models are designed to be connected to their associated controller in star
fashion wherein each FDD unit has its own complete umbilical cable connection to the
controller, with no interconnection between FDD units. Standard FDD model units
are always in a ready state for reading or writing operation after initial preparation
and turn on.
Daisy-chain models are designed so that one to four FDD units may be connected
seria.lly to a common contro.ller. The controller continously monitors the operational
readiness of each FDD in its chain and commands and controls the reading and writing
operation of any selected FDD unit in its chain.
77834769-U
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1

1.3.1 PHYSICAL DESCRlPTION
The physical dimensions for the equipment are as follows:
Height
Width
Depth
Weight
4.97 inches (126. 2mm)
8.78 inches (223.0mm)
14.24 inches (361.7mm)
12 lbs. (5.44 kgm)
1 .3.2 ELECTRICAL DESCRIPTION
The electrical specifications for the equipment are as follows:
• DC Power Source (Supplied by HOf;;t Equipment)
Without Stepper-Power Reduction
+24 Volts (± 10%) @ 1.·3 A Typical
+ 5 Volts (± 5%) @ O. 8 A Typical
With Stepper-Power Reduction
r 1. 3A Typical, Stepping
+24V
(±10%) @{O. 3A Typical, Not Stepping
+ 5V (:!: 5%) @ 1.0 A Typical, Not St~pping
• A. C. Power Source - Refer to the FDD configurator or FDD nameplate
to determine A. C. Power requirements.
1 .3.3 PERFORMANC.E CHARACTERISTICS
The equipment specifications for the FDD are as follows:
1-2
• ACCESSING TIME
Maximum Access Time
Maximum One-Track Access Time
A verage Access Time
• RECORDING
770 ms
20 ms
263 ms
Mode
Density (nominal) Double
Freq. MFM
1836 B.PI(72.3 BPmm) 3672 BPI (144.6 BPmm) Outer Tracl(
3268 BPl(128.7 BPmm) 6536 BPI (257.3 BPmm) Inner Tract(
Data Transfer Rate
Bits/Byte
Bits/Track
Tracks
Sectors
• DATA CAPACITY
Bytes/Track
Bits/Track
Bits/Diskette
249, 984 bits/sec
8
41,664
77
Format Determined
5,208
41,664
3,208, 128
-----.-- .. -----.--- - ...
499, 968 bits/sec
8
83,328
77
Format Determined
10,416
83,328
6,416,25'6
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