NEC D2246 Maintance Manual
D2246
8-INCH
WINCHESTER
DISK
DRIVE
MAINTENANCE
GUIDE
NEe
NEe
Information
Systems,
Inc.
819-000080-5001
Rev.
00
12-83
LIABILITY
DISCLAIMER
NEC
Information Systems, Inc. (NECIS) products are warranted in accordance with the
terms
of
the applicable NEC Information Systems, Inc.
product
specification. Product
performance
is
affected by system configuration, software, the application, customer
data,
and
operator control
of
the system among other factors. While NECIS products are
considered to be compatible with most systems, the
product
functional implementation
by customers
of
the product may vary.
Therefore, the suitability
of a product
for a specific application must be determined by
the customer and
is
not
warranted by NECIS.
This manual
is
as complete
and
factual as possible
at
the time
of
printing; however, the
information in this manual may have been updated since
that
time. NEC Information
Systems, Inc. reserves the right
to
change the functions, features,
or
specifications
of
its
products
at
any time, without notice.
NEC
Information Systems, Inc. has prepared this document for use by NECIS
employees
and
customers. The information contained herein
is
the property
of
NECIS
and
shall not be reproduced without prior written approval from
NEelS.
First Printing - December
1983
Copyright
1983
NEC Information Systems, Inc.
5 Militia Drive
Lexington, MA
02173
Printed in U.S.A.
Contents
Chapter 1 System Overview
1.1
D2246 System
1.2 Disk Circuitry
1.3
Power
1.4 Features
1.5
Related
1.6 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.7
Options...........................................................
Chapter 2 Installation Procedures
2.1
Unpacking/Repacking
2.2 Terminating
2.3
Jumper
2.4 Switch
Cabinet/Rack
2.5
2.6 Cable Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.7 Lock
Requirements.
1.4.1 Enhanced Seek Time
1.4.2 Rapid
Compact
1.4.3
1.4.4 Simplified
1.4.5 Design Reliability. . . . . . . . . . . . . . . . . . . . .
1.4.6
Standard
1.4.7
Safety.......................................................
1.4.8 System Configuration Flexibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Document.
Requirements.
Settings.
2.4.1 Installation Switch Assembly
Control
2.4.2
2.4.3 Sector Select Switch
2.6.1 Interface Cables
2.6.2 System
Power Cable
2.6.3
Control
Design.
.....................................................
..........................................................
Data
Mounting
Interfaces
Resistors.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mode Switch
Installation
Ground
Assembly
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..........................................
Transfer
Maintenance.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.................................................
Rate.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
...........................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
...........................................
..............................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
...................................
Assembly.
Assembly.
...........................................
..............................................
Cable
.........................................
....
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
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..
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Page
1-1
1-4
1-4
1-4
1-4
1-4
1-4
1-6
1-6
1-6
1-6
1-6
1-7
1-7
1-7
2-1
2-2
2-4
2-4
2-5
2-6
2-7
2-16
2-16
2-16
2-18
2-18
2-18
Chapter 3
3.1
General Maintenance
3.2 Maintenance Tools
3.3 Preventive
Troubleshooting...........
3.4
3.5 Servo System Signals
3.6 Seek
Preventive Maintenance and Troubleshooting
Maintenance.
Operations Testing
3.6.1 Repeat Seek
3.6.2
One-Cylinder Seek Operation
Rules.
.................................................
................................................
Operation
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.............................................
........................................
...................................
III
..
..
..
3-1
3-1
3-2
3-2
3-13
3-18
3-18
3-18
Contents (cont'd)
Chapter 4 Removal and Replacement Procedures
4.1
G9QST (Logic
4.2 G9QSN (Read/Write) PCB
4.3
Earth
Pad Assembly
4.4 G9QSQ (Power Amplifier) PCB
4.5
Motor
Chapter 5 Adjustments
5.1
Required
Stator
and
Servo) PCB Removal
Removal.
Assembly Removal
Tools... . ........
..............................
Removal.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal.
. . . . . . . . . . . . . . . . . . . . . . . . . . .
.....................................
.... . ............. .............
.
..
.......
5.2 Servo Offset Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Seek Speed Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 6 Illustrated Parts Breakdown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 7
7.1
General
DKUOOO-H3PM
Description.......
3-Input
DC
Regulator Option
.
....
....... . .....
.. . ...
....
.... . ... ...
7.2 Interface Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.2.1
DC
Power Connector (P4)
7.2.2 Signal
7.2.3
DC
7.3 Installing the 3-Input
Chapter 8
8.1
General Description
DKU-HDPI
Ground
Terminal.
Power Input Requirements
DC
Dual-Port Interface Option
................................................
8.2 Switches and Indicators
8.2.1 Port A (Route
8.2.2 Port B (Route
8.2.3 Release
Timer.
0) Switches and Indicators. . . . . . . . . . . . . . . . . . . . . . .
1)
Power
.............................................
Switches
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.....................................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.................................
Regulator.
and
Indicators.
. . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .
8.3 Drive Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.4 Interface
..........................................................
8.5 Status Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.5.1 Release
8.5.2 Priority
8.6 Installing the Dual-Port
Command
Select.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
............................................
Interface.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
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Page
4-1
4-3
4-3
4-4
4-6
5-1
5-1
5-3
5-1
7-1
7-2
7-2
7-3
7-3
7-4
8-1
8-2
8-3
8-3
8-3
8-3
8-4
8-4
8-4
8-4
8-7
Appendix A Schematic Diagrams
A.1 Signal Tracing Scheme
A.2
Drawings.........................................................
Appendix B Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..............................................
IV
..
A-I
A-I
B-1
Contents (cont'
d)
Page
Appendix C DKUOOO-HLOG
Diagnostic Panel
C.I
Control Panel
..
0 0
000 0 000
000
0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 0
000
0 • 0 0 0 0 0 0 • 0 0 0
•• 0 000
0 0 C-I
Col.1
Keypad 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-4
C.I.2
LED
Status Indicators 0 0 0 0 0 0 0 0 0 • 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-6
C.I.3
LCD
Display Window 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-6
C.1.4
Diagnostic Panel Summary Charts 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-6
C.2
Status Mode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 • 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-6
C.2.1
Starting Status Mode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-6
C.2.1.1
Drive Status 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-7
C.2.1.2 Cylinder
and
Head
Addresses 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
C-ll
C.2.2 Using Status Mode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
••••
0
••••••••••••
C-II
C.2.3 Ending Status Mode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
C-II
C.3 Test Mode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
C-II
C.3.1 Starting Test Mode
00000.0000000000000000000000000000000000000
C-II
C.3.1.1
Input
Parameters 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
C-II
C.3.1.2 Seek Modes
00000000000000000000000000000000000000000000
C-13
C.3.2
Using Test Mode
000000000000000000000000000000000000000000000
C-14
C.3.3
Ending Test Mode
..
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
000000000000
C-14
C.4
Log Read Mode
0000000000000000000000000000
o.
0000000000000000000000
C-14
C.4.1
Error/Count
Log
000000000000000000000000000000000000000000000
C-14
C.4.2
Sequential Operations Log 0 0 0 0 0
0000
0 0 0 0 0 0 0 0 0 0 0 0
00000
0 0 0 0 0 0 0 0 0 0 0 C-16
C.4.3
Ending Log Read Mode 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C-17
v
Illustrations
Figure Title Page
1-1
D2246
Major
Components.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
1-1
1-2
D2246 Disk
and
Read/Write
Head
Arrangement.
. . . . . . . . . . . . . . . . .
..
1-2
1-3
D2246 Servo Disk
Surface.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
1-3
1-4
D2246
Functional
Block
Diagram
................................
1-4
1-5
Daisy-Chain System Configuration
...............................
1-6
1-6
Radial System
Configuration.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
1-7
2-1
D2246
Packaging.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
2-1
2-2
G9QST
Terminating Resistor
and
Jumper
Locations
................
2-2
2-3 Terminating Resistors in Radial
System.
. . . . . . . . . . . . . . . . . . . . . . . . .
..
2-2
2-4 Individual Drive
Termination/Daisy-Chain
System. . . . . . . . . . . . . . . .
..
2-3
2-5 Last Drive
Termination/Daisy-Chain
System.
. . . . . . . . . . . . . . . . . . . .
..
2-3
2-6
DIP
Switch Assembly
Locations.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
2-4
2-7 Installation
DIP
Switch
.........................................
2-5
2-8
Control
Mode
DIP
Switch.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
2-6
2-9 Sector Select Switch
............................................
2-7
2-10 Sector
Allocation.
. .
..
. . . . . .
.. . ... . ..
. . .
.. . ..
...
. .
..
. .
..
..
... . ..
2-7
2-11
Mounting
Bracket
..............................................
2-16
2-12 Horizontal
and
Vertical Installation
...............................
2-16
2-13 Interface Cable Connections
.....................................
2-17
2-14 Cable
A/Daisy-Chain
System
....................................
2-17
2-15 Signal
Ground
and
Power Connections . . . . . . . . . . . . . . . . . . . . . . . . . .
..
2-18
2-16 Lock
Control
Assembly
.........................................
2-18
3-1
Troubleshooting Flowcharts
.....................................
3-2
3-2
G9QST
Test
Point
Locations
.....................................
3-13
3-3 Repeat Seek Using
TPI
..........................................
3-18
3-4 One-Cylinder Seek Using
TPI
....................................
3-18
4-1
D2246
Board
Cover.
. . . . . . . . .
.. . ..
. . . . . . .
..
. . .
..
. . .
..
..
..
. .
.. ..
4-2
4-2
G9QST
Cable Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
4-2
4-3 D2246 Air
Separators.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
4-3
4-4
G9QSN
Cable
Connectors.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
4-4
4-5 G9QSQ Cable
Connectors.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
4-5
4-6 D2246
Fan.
. . .
..
. . . .
..
. . . . . . . . . . . . . . . . . .
..
. . .
..
. . . . .
..
. . . . . .
..
4-5
4-7 D2246
Stator
Assembly
.........................................
4-6
5-1
Servo Offset
and
Seek Speed Adjustment Test Points
................
5-2
5-2 Servo
Offset Waveform
.........................................
5-2
5-3 Seek Speed Waveform
..........................................
5-2
5-4 Transient Response Waveform
...................................
5-3
5-5 Increment Seek (Cylinder
000
to
Cylinder 691)
Waveform.
. . . . . . . . .
..
5-4
6-1
D2246
Standard
Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
6-2
6-2 D2246
Head/Disk
Enclosure (External Parts)
......................
6-4
VI
Illustrations (cont'
d)
Figure
Title
Page
7-1
3-Input
DC
Regulator Block
Diagram.
. . . . . . . . . . . . . . . . . . . . . . . . . .
..
7-1
7-2 3-Input
DC
Regulator Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
7-2
7-3
P4
Connector.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
7-2
7-4 Installing the 3-Input
DC
Regulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
7-4
8-1
Dual-Port System
Cabling.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
8-2
8-2 Dual-Port Control Switches and Indicators. . . . . . . . . . . . . . . . . . . . . . .
..
8-2
8-3
Unit Select Timing for Dual-Port Option
..........................
8-5
8-4 Sample Priority Select
Timing.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
8-6
8-5
Installing the Dual-Port Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
8-7
A-I Schematic
Format
..............................................
A-2
B-1
D2246 Basic Assembly Dimensions
...............................
B-7
B-2
D2246 Standard Assembly
Dimensions.
. . . . . . . . . . . . . . . . . . . . . . . . .
..
B-7
B-3
Cable A
Signals.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
B-8
B-4 Cable B Signals
................................................
B-9
C-l
Diagnostic
Panel.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
C-2
C-2 Attaching the Diagnostic Panel to the
Drive.
. . . . . . . . . . . . . . . . . . . . .
..
C-3
C-3 Diagnostic Panel Cable and
Connector.
. . . . . . . . . . . . . . . . . . . . . . . . .
..
C-3
C-4 Status Mode Display
Format.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
C-6
C-5 Status Mode
Error
Display Format
...............................
C-ll
C-6 Low Cylinder Parameter Display
.................................
C-12
C-7 High Cylinder Parameter Display
.................................
C-12
C-8 Interval Timing Parameter Display
................................
C-12
C-9 Seek Mode Display
.............................................
C-13
C-I0
Error/Count
Log Display
Format
................................
C-15
C-ll
Error/Count
Log Power-On Count
...............................
C-16
C-12
Error/Count
Log
Error
Display
Format
...........................
C-16
C-13 Sequential Operations Log Display
Format
........................
C-17
C-14 Sequential Operations Log Entries
................................
C-17
Vll
Tables
Table
Title
Page
1-1
DC
Power
Requirements.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
1-5
1-2
Available Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
1-7
2-1
Sector Select Switch Settings (Segment 1 =
0)
. . . . . . . . . . . . . . . . . . . . .
..
2-8
2-2 Sector Select Switch Settings (Segment 1 =
1)
.......................
2-12
3-1
Test Point Signal Outputs
.......................................
3-14
3-2 G9QST Servo Signals
...........................................
3-15
4-1
D2246 Field Replaceable
Components.
. . . . . . . . . . . . . . . . . . . . . . . . . .
..
4-1
6-1
D2246
Standard
Assembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
6-1
6-2
Head/Disk
Enclosure External
Parts.
. . . . . . . . . . . . . . . . . . . . . . . . . . .
..
6-3
7-1
P4 Pin Assignments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
7-3
7-2
DC
Power Requirements
........................................
7-3
A-I Schematic Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-I
B-1
Operating Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
B-1
B-2
Design Specifications
...........................................
B-3
B-3
Physical
Dimensions.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
B-3
B-4 Interface Cable Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
B-4
B-5
Power Cable Descriptions
.......................................
B-4
B-6
Option Cable Description
.......................................
B-4
B-7
Interface Connector
Descriptions.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
B-5
B-8
DC
Power Cable Connector Description. . . . . . . . . . . . . . . . . . . . . . . . .
..
B-5
B-9
AC Power Cable Connector
Description.
. . . . . . . . . . . . . . . . . . . . . . . .
..
B-5
B-I0 3-DC Option Cable Connector Descriptions. . . . . . . . . . . . . . . . . . . . . .
..
B-6
B-ll
Operator
Panel Cable Connector
Descriptions.
. . . . . . . . . . . . . . . . . . .
..
B-6
C-l
Mode Selection Keys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
C-4
C-2 Diagnostic Panel
Functions.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
C-5
C-3 Disk Drive
Operational
States.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
C-7
C-4 Drive Status
Reports.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
C-7
C-5 Seek Modes
...................................................
C-13
viii
Abbreviations
A
Ampere
ac alternating current
AM
Address Mark
AWG
American Wire Gauge
CA Cylinder Address
CRC Cyclic Redundancy Check
dc direct current
DE
Disk Enclosure
DIP
Dual-inline-packaged
DKC
Disk Controller
DKU
Disk Unit
ECC
Error
Correction Code
EOR
End
of
Record
GND
Ground
HA
Head
Address
HEX
Hexadecimal
1GB
Inner
Guard
Band
I/O
Input/Output
LED
Light emitting diode
m meter
MB Megabyte
MFM
Modified Frequency Modulation
MHz
Megahertz
mm
Millimeter
ms
Millisecond
mV
Millivolt
MTBF
Mean Time Between Failures
MTTR
Mean Time to Repair
NRZ
N on-Return-to-Zero
ns
Nanosecond
OGB
Outer
Guard
Band
PCB
Printed Circuit Board
PLO
Phase Locked Oscillator
RMS Root-Mean-Square
ROM
Read only memory
RPM
Revolutions per Minute
R/W
Read/Write
SA
Sector Address
TTL
Transistor/Transistor Logic
V
Volt
f.ls
microsecond
Chapter
1
System Overview
The D2246
is
a new addition to the
NEe
D2200 series
of
disk drives. It
is
a compact,
highly reliable, low-cost unit
and
is
fully compatible with earlier D2200 models.
It
offers
85
megabytes (MB)
of
unformatted
data
storage on four 8-inch platters. Actual storage
capacity depends upon the formatting method used.
1.1 D2246
SYSTEM DESIGN
The D2246 uses fixed-disk, Winchester-type technology, which provides the most
advanced method
of
storing
and
retrieving large amounts
of
data. Each D2246 disk drive
contains four 8-inch platters sealed within a protective, air-tight enclosure. This enclosure protects the recording piatters from atmospheric dust
and
dirt to improve operational reliability. A spindle, a drive motor, a rotary actuator assembly, and movable
read/write heads are also contained within the enclosure. Figure
1-1
shows the major
components
of
the D2246.
Figure
1-1
D2246 Major Components
1-1
3-INPUT
DC
'I
I,
:1
,I
'I
....
.1.;
R/W
PREAMP
PCB
Figure
1-2
shows the arrangement
of
recording platters
and
read/write heads within the
D2246.
DATA DISK
I
DATA DISK
I
DATA DISK
I
DATA DISK
I
I
I
692
CYLINDERS
SPINDLE
I
I
I
I
I
DATA SURFACE
A
HEADS
HEAD4
V
DATA SURFACE
DATA SURFACE
A
HEAD2
HEAD 1
v
DATA
SURFACE
DATA
SURFACE
A
HEAD3
HEADO
V
DATA
SURFACE
A
SERVO HEAD
Figure
1-2
D2246
Disk
and
Read/Write
Head
Arrangement
1-2
The servo disk surface
is
shown in Figure
1-3.
Figure 1-3 D2246 Servo Disk Surface
The Index signal
is
a six-bit pattern written along one radius
of
the servo surface.
It
identifies the beginning
of
a recording track. The index pattern repeats each time the
radius intersects one
of
the recording tracks.
The servo
data
zone contains 692 concentric recording tracks. Each recording track
contains prerecorded positioning data, including clock and synchronization signals, that
provide information to place and maintain the read/write heads on track.
The inner
and
outer guard bands bracket the servo data zone. They contain recurring
six-bit patterns to distinguish them from the servo data zone.
The landing zone
is
a silicon-coated surface where the read/write heads rest when the
recording disks are not spinning. During read, write,
and
seek operations the heads
"float"
approximately
20
microinches above the surface
of
the disk.
1-3
1.2 DISK
CIRCUITRY
A block diagram
of
a D2246 disk drive
is
shown
in
Figure 1-4. The functional components are the interface, the read/write circuits, the servo control, and the motor control
circuits.
~
DISK
DRIVE
CONTROLLE
(SMDI
DC
POWE
-
-
R:::::
-
r--
-
--
LOGIC & SERVO
READ/WRITE
READ
DATA/CLOCK
WRITE
DATA/CLOCK
J
READPLO&
READ
I
_
SEPARATOR
CIRCUIT
I
-a
"eA,GA"
CONTROL
I
NRZ
TO
MFM
WRITE
CONVERTER
CIRCUIT
f
j
~SO-9~
I
"eA","m
I
TAG
3
FAUL
T SENSE
SMD
I
TAG
2
CONTROL
TAG
1
LSI
!L.
I
HEAD
TAG
4
l
SELECT
-
A
SENSE
LINES
SERVO
~
CONTROL
,
l~
LSI
~
I
/I
PHASE
SERVO
UNIT
DETECTOR
PLO
t-
SELECT
It
r-
+
~
t
I
",m,o,
SIGNAL
AGC-AMP
MAPPED
DEMODULATOR
PROFILE
t
VELOCITY
j
GENERATOR
t
__
t5V
r H
SERVO
~
SERVO
POWER
__
-5V
ANALOG
AMP
f-+-
t12V
AMOTO"
I
r--
-12V
MICRO-PROCESSOR
r--
t24V
CONTROL
SYSTEM
(MCSI
/
-,
CONTROL
l
AMP
I
POWER AMP
Figure
1-4 D2246
Functional
Block
Diagram
r
~
DE
ASSEMBLY
"
r
-
H
"eA"WR'"
LSI
I
DATA
HEADS
r-
POSITIONER
I
SERVO
HEAD
lH
PRE-AMP
r
-
DISK
--,-
SPINDLE
I
MOTOR
L
The interface circuits route data, addresses, status information, and control signals
between the disk drive and the controller.
The read/write circuits control the transfer
of
data from the disk (read operation), and to
the disk (write operation). During a write operation, the circuits receive serial nonreturnto-zero
(NRZ) format data from the controller and convert the data to a modified
frequency modulation (MFM) format. The MFM data is then written
on
the disk.
During a read operation, the circuits read and amplify the data from the disk, convert it
from MFM to
NRZ format, and send the NRZ data serially to the controller.
The servo control reads the data prerecorded on the servo disk. The servo control uses
this data to position and maintain the read/write heads on the correct cylinder. The
motor control circuits drive the spindle motor.
1-4
1.3 POWER REQUIREMENTS
D2246 disk drives operate on externally supplied dc power.
DC
power requirements are
listed in Table
1-1.
Table 1-1 DC Power Requirements
REQUIRED
DAMAGE
RIPPLE
VOLTAGE
TOLERANCE
THRESHOLD
CURRENT
(PEAK TO PEAK)
+5.0V
±0.25 V
±10%
4.0A
100mV
-5.0V
±0.25 V ±10%
0.5
A
100mV
+12.0V
±0.60 V ±10%
0.6
A
100mV
-12.0 V
±0.60 V
±10%
0.5
A
100
mV
+24.0 V
±2.40 V ±10%
2.5
A*
240mV
5.0 A**
*2.5 A - average running current
**5.0 A - peak starting current (25 seconds maximum duration)
All power line voltages must be established within
500 milliseconds (ms)
of
power on.
Voltages must be enabled in the following order: +5
V,
-5
V,
±12
V,
+24
V.
When power
is
turned off, lines must be disabled in the reverse order: +24
V,
±12
V,
-5
V,
+5
V.
1.4 FEATURES
Shorter access times, high-speed
data
transfers,
and
mechanical reliability are required
for efficient computer network operations. To meet these demands the D2246 disk drive
offers the following features.
1.4.1 Enhanced
Seek Time
Seek time
is
the time required to find requested
data
on the disk. The D2246 has
an
average seek time
of
25
milliseconds (ms), and a maximum
of
50
ms.
1.4.2 Rapid
Data
Transfer Rate
The D2246 provides a data transfer rate
of
approximately 1.2
MB
per second.
1.4.3 Compact Mounting
The compact size
of
the D2246 allows for either horizontal
or
vertical mounting in a
limited space. The drive's lock mechanism
is
easily accessible even after the drive has
been placed within a system cabinet.
The D2246 also features an integrated cooling fan
that
reduces space
and
power
requirements.
1-5
1.4.4 Simplified Maintenance
The air-tight, sealed
disk/head
assembly
and
the D2246's simplified design produce a
disk drive
that
requires no periodic maintenance. Neither installation
nor
field service
requires special tools.
Motor
electronics are placed outside the
head/disk
assembly
and
do
not need "clean
room"
repair facilities.
An
optional diagnostic panel
is
available for test
and
maintenance purposes (see Appen-
dix C).
1.4.5 Design Reliability
Lightweight, contact-type
start/stop
heads
that
reduce damage
to
the heads
and
disks
are used within the D2246 disk drive. A simplified rotary actuator, a directly coupled,
brushless dc motor,
and
a closed-loop air circulation system are the drive's major
mechanical components. The control logic
is
microprocessor controlled
and
designed
to
minimize electronic components. This design strategy ensures high reliability
and
low
cost.
1.4.6 Standard Interfaces
The D2246 uses standard original equipment manufacturer interfaces for connection to a
disk controller and
to
a power supply.
1.4.7 Safety
The D2246 conforms to Underwriter's Laboratories Safety Regulation UL478.
1.4.8 System Configuration Flexibility
A maximum
of
four D2246 disk drives can be connected
to
a single controller in either a
daisy-chain
or
radial system (see Figures
1-5
and
1-6).
DISK DRIVE CONTROLLER
SG
AO
BO
B1
Bn
r
CABLEA
CABLE B
/
-
\
/
-
\
V
V
-
~
V
-
~
si)
A
IB~
A
IB-
A
Is~
*TERM
*TERM
*TERM
DISK DRIVE
DISK DRIVE
---
DISK DRIVE
0
1
4 (maximum)
* TERMINATING RESISTORS INSTALLED ON EACH DRIVE
Figure 1-5 Daisy-Chain System Configuration
1-6
DISK DRIVE CONTROLLER
SG
AO
BO
SG
A1
B1
SG
An
Bn
S~
A
1;-
~~
A
1;-
S~
A
IB
....
*TERM
*TERM
*TERM
DISK DRIVE
DISK DRIVE
---
DISK DRIVE
a
1
4
(maximum)
* TERMINATING RESISTORS INSTALLED
ON
EACH DRIVE
Figure 1-6 Radial System Configuration
1.5 RELATED
DOCUMENT
For
additional information on the D2246 disk drive, refer to the D2246 8-Inch Winchester
Disk
Drive Product Description (NEC document 819-000080-4001).
1.6 SPECIFICATIONS
Product
specifications are listed in Appendix
B.
1.7 OPTIONS
Table
1-2
lists available options for the D2246 disk drive.
Table 1-2 Available
Options
OPTION
DESCRIPTION
3-Input
DC
Regulator Option
Supplies internal dc
"power
set" (+24
V,
+
12
V,
+5
V,
-5
V,
-12
V)
from external dc
input
of
+24
V,
+5 V,
and
-12
V.
Dual-Port Option
!
Enables disk drive interface with two con-
I
trollers.
!
\.
DC
Power Supply
I
Supplies internal dc
"power
set"
from ac
input power. Provides power for two disk
drives.
Diagnostic Panel
I
Tests and monitors disk drive operation.
1-7
Chapter
2
Installation
Procedures
This chapter provides procedures for installing a D2246 disk drive. When preparing the
installation site, refer to the environmental specifications listed in Appendix
B.
2.1
UNPACKINGIREPACKING
Before unpacking the disk drive, examine the shipping carton for damage.
If
damage has
occurred, notify the carrier immediately.
Do
not open the carton until the carrier's
representative
is
present.
If
there
is
no damage to the shipping carton, use these procedures to unpack the disk
drive. Failure to follow these procedures can void the product warranty.
1.
Open the top
of
the shipping carton.
2.
Remove the top packing brace (see Figure 2-1).
3.
Carefully remove the disk drive from the shipping carton.
4.
Remove the D2246 from the plastic shipping bag.
5.
Save all packing material for reshipping.
6.
Check all items against the bill
of
material to insure
that
no items are missing.
7.
Check all items for shipping damage.
To repack the disk drive, reverse these procedures.
TOP PACKING BRACE
02246
DISK DRIVE
SHIPPING
CARTON
Figure
2-1
D2246
Packaging
2-1
2.2 TERMINATING RESISTORS
Terminating resistors are installed on the G9QST logic and servo printed circuit board
(PCB) as shown in Figure
2-2.
G9QST LOGIC
AND
SERVO
PCB
DCJC3
c:::::3.c]
CJD
~~
c:::::3
CJ
c:::J
c::J
CJ
0 0
c:::J
CJ~
[]
0 [JJ
0000
o 0
TERMINATING RESISTORS
Figure 2-2 G9QST Terminating Resistor and Jumper Locations
If
the D2246 drive
four terminating resistors in place as shown in Figure 2-3. Terminating resistors can be
either 150a
or
56
JUMPERS
EJ
~
lOB
is
connected to the controller in a radial configuration, install a set
JPl
CPU
RESET
JP6
FIRST
RETRY
I
JP8
FAULT (FAULT ENABLED)
lONE
STEP (JUMPER REMOVED)
ONIOFF
(RETRY
ENABLED)
n.
of
DISK DRIVE CONTROLLER
SG
~~
TERMINATING RESISTORS INSTALLED ON EACH DRIVE
*
AO
A
*TERM
DISK DRIVE
0
BO
r;-
SG
S~
A1
A
*TERM *TERM
DISK DRIVE
1
B1
r;-
Figure 2-3 Terminating Resistors
2-2
---
in
Radial System
SG
S~
An
A
DISK DRIVE
4 (maximum)
Bn
,;-
In
a daisy-chain
configuration,
two
types
of
termination
methods
can
be
used.
To
terminate
individual drives, install a set
of
four
150n resistors in
each
drive as
shown
in
Figure 2-4.
DISK DRIVE CONTROLLER
SG
AO
BO
B1
Bn
r
CABLEA
CABLE B
- -
/
-
\ /
-
\
V
V
~
V
~
~~
A
IB~
A
I;
A
IB~
*TERM
*TERM *TERM
DISK DRIVE DISK DRIVE
---
DISK DRIVE
0
1
4
(maximum)
* TERMINATING RESISTORS INSTALLED ON EACH DRIVE
Figure 2-4 Individual Drive Termination/Daisy-Chain System
To
terminate
the last drive, install a set
of
four
56n
resistors in
the
final drive
of
the chain
as shown in Figure 2-5.
DISK DRIVE CONTROLLER
SG
AO
BO
B1
Bn
r
CABLEA
-
CABLE B
/
-
\ /
-
\
V
V
-
~
V
-
~
S~
I
A
I
ls-
I
A I
[B-
A
IB~
*TERM
DISK DRIVE
DISK DRIVE
---
DISK DRIVE
0
1
4
(maximum)
* TERMINATING RESISTORS INSTALLED ONLY ON LAST DRIVE
Figure 2-5
Last
Drive Termination/Daisy-Chain System
2-3
2.3
JUMPER
Three
location
jumper
Figure 2-2. Insure
REQUIREMENTS
settings
of
these three
must
be verified before power is applied
jumpers
that
settings
Do not alter these
for factory adjustments only.
(JPl,
match
jumper
JP6,
and
those shown in Figure 2-2.
CAUTION
settings. They are intended
JP8)
on
the
to
the disk drive. The
G9QST
PCB
is
shown in
SWITCH
2.4
Three eight-segment, dual-inline-packaged
and
servo PCB configure
sector count.
SETTINGS
the
D2246 to communicate with the controller
DIP
switch assembly locations are shown in Figure 2-6.
INSTALLATION SWITCH
;\®i
CjJcsD
o
ornIIIIlJ
~C1
~CJ
SECTOR
SWITCH SWITCH
C1
DDO[]
C1
C]
DO
SELECT CONTROL MODE
C1C3
CJC3CJ
C]
C]
C]
C]
(DIP)
D
D
D
switch assemblies on the
0000000
o
C5
c:::::s
CJ
C3
C]
c:::J 0
C]
c::::::3
C]
~~CJ
DOD
~CJc=J
0000
o 0
G9QST
and
~
[]::J
logic
set the
Figure 2-6
DIP
Switch Assembly Locations
2-4
2.4.1 Installation Switch Assembly
The installation switch assembly, shown in Figure 2-7, sets the device address
and
controls the power-on sequence. Segments
1, 2 and
5 are set to
O.
Segments 3
and
4 assign the device address, a hexadecimal number from 0 to
3.
Segment 6 enables a 30-second delay in the start-up time
of
the spindle motor. This
segment can be used in dual-drive systems to insure
that
both
drives
do
not
overload the
power supply by simultaneously activating their power-up sequence.
Segment 7
is
set to correspond to the mounting position
of
the drive.
Segment 8 places the D2246 in local
or
remote mode
at
power-on.
SETTOO
DEVICEADDRESS
t----....L-...J
I'
ON
o
OFF
~---f
START -up DELAY ENABLE
~----f
SET
TO
0
Figure 2-7 Installation DIP Switch
2-5
1 REMOTE MODE
o LOCAL MODE
1 VERTICAL
o HORIZONTAL
2.4.2 Control Mode Switch Assembly
The
control
mode
switch assembly (shown in Figure 2-8) configures the D2246
to
communicate
with the disk controller
and
enables certain
optional
drive features.
Segment 1
is
set
to
1.
Segments 2
and
3 are set
to
O.
Segment 4 enables the Address
Mark
function.
Segment 5 enables the
Read
Sector
function.
When
segments 5
and 7 of
the
control
mode
switch assembly
are
set
to
1,
Tag 4 can
be used with
bus
bits 8
and 9 to
request the
current
sector address.
The
D2246 issues the
current
sector address across the sense lines.
Segment 6 enables the
Format
Write Release
Option
used with some controllers.
Segment 7 enables the
Tag
4 line.
Segment 8 enables the controller interface.
SETTO
1
SET TO 0
1--_.1..-1
1 ON
OOFF
INTERFACE ENABLE
TAG 4 ENABLE
ON LINE
OFF LINE
L..-
__
.....
FORMAT
WRITE RELEASE ENABLE
ADDRESS
MARK
ENABLE
1-----
......
~----f
READ SECTOR ENABLE
Figure 2-8 Control Mode
DIP
Switch
2-6
2.4.3 Sector Select Switch Assembly
The
sector select switch assembly (see Figure 2-9) sets the
number
of
sectors
per
track.
Any
number
of
sectors
up
to
128
can
be selected.
1 2 3 4 5 6 7 8 1
ON
~ ~
~
~
~
~ ~
~
0
OFF
SECTOR
COUNT
DISPOSITION SWITCH
Figure 2-9 Sector Select Switch
Segment 1
of
this assembly determines
the
disposition
of
odd
or
remainder
bytes. These
are
extra bytes
that
must
be allocated when the available bytes
per
track
are
not
evenly
divisible by the
number
of
sectors
per
track.
With
segment 1 in the 0 position,
odd
bytes
are
grouped
together
in
an
extra
sector
at
the
end
of
the
track.
With
this segment in the 1
position, the last sector
is
reduced
to
account
for
odd
bytes.
INDEX
Jl
n
If
PULSE
I
I
I
"SA"
"SA"
"SA"
"SA"
I
"SA"
I
SECTOR
0
n
1
~S
31
n
32
n(33)
I
0
rL
PULSE
F
"0"
(620
(620)
(620)
(620)
f-20~
(620)
BYTES
BYTE
I
(EXTRA
SECTOR)
I
"SA"
"SA"
"SA"
"SA"
I
"SA"
I
SECTOR
0
n
~$
31
n
32
I
0
rL
PULSE
(621)
(621 )
(621 )
608
BYTE
I
(621 )
F"1"
I
(LAST SECTOR)
Figure 2-10
Sector Allocation
Figure
2-10 illustrates the allocation
of
33
sectors with segment 1
of
the sector select
switch assembly in
both
the 0
and
1 positions.
2-7
Tables
2-1
and
2-2
list sector select switch settings
and
resulting sector allocations for the
D2246
disk drive.
Table 2-1 Sector Select Switch Settings
(Segment 1
= 0)
SECTOR
SWITCH
SETTING
Id2bl41516bl81
,-+-I~~I-+-_.
= 0
, , , 1 1
If
TRACK
=
20,480
BYTES
SECTORS
2625242322212°
PER
TRACK
o 0 0 0 0 0 1 1
0000010
2
0000011
3
0000100
4
o 0 0 0
101
5
0000110
6
o 0 0 0 1 1 1 7
0001000
8
000
100
1 9
o 0 0 1 0 1 0
10
000
1 0 1 1
11
o 0 0 1 1 0 0
12
o 0 0 1 1 0 1
13
o 0 0 1 1 1 0
14
o 0 0 1 1 1 1
15
o 0 1 0 0 0 0
16
0010001
17
o 0 1 0 0 1 0
18
o 0 1 0 0 1 1
19
o 0 1 0 1 0 0
20
o 0 1 0 1 0 1
21
o 0 1 0 1 1 0
22
o 0 1 0 1 1 1
23
o 0 1 1
000
24
o 0 1 1 0 0 1
25
o 0 1 1 0 1 0
26
o 0 1 1 0 1 1
27
o 0 1 1 1 0 0
28
o 0 1 1 1 0 1
29
o 0 1 1 1 1 0
30
2-8
BYTES
PER
SECTOR
20480
10240
6826
5120
4096
3413
2925
2560
2275
2048
1861
1706
1575
1462
1365
1280
1204
1137
1077
1024
975
930
890
853
819
787
758
731
706
682
EXTRA
SECTOR
BYTES
o
o
2
o
o
2
5
o
5
o
9
8
5
12
5
o
12
14
17
o
5
20
10
8
5
18
14
12
6
20
Table 2-1 Sector Select Switch Settings (cont'd)
(Segment 1
= 0)
SECTOR SWITCH
SETTING
112bI415/617/81
I-+I-+-+-+-+-+-+---
.....
~
= 0
I
!"
!
SECTORS
2625242322212°
PER
TRACK
0011111
31
o 1 0 0
000
32
o 1 0
000
1
33
o 1 0 0 0 1 0 34
o 1
000
1 1
35
o 1 0 0 1 0 0 36
o 1 0 0 1 0 1 37
o 1 0 0 1 1 0
38
o 1 0 0 1 1 1
39
o 1 0 1 0 0 0 40
o 1 0 1 0 0 1
41
o 1 0 1 0 1 0 42
o 1 0 1 0 1 1 43
0101100
44
o 1 0 1 1 0 1 45
o 1 0 1 1 1 0 46
o 1 0 1 1 1 1 47
o 1 1 0 0 0 0
48
o 1 1
000
1 49
o 1 1 0 0 1 0 50
o 1 1 0 0 1 1
51
o 1 1 0 1 0 0 52
o 1 1 0 1 0 1
53
o 1 1 0 1 1 0 54
o 1 1 0 1 1 1
55
o 1 1 1
000
56
o 1 1 1 0 0 1
57
o 1 1 1 0 1 0
58
o 1 1 1 0 1 1
59
o 1 1 1 1 0 0 60
2-9
TRACK
= 20,480 BYTES
BYTES
PER
SECTOR
660
640
620
602
585
568
553
538
525
512
499
487
476
465
455
445
435
426
417
409
401
393
386
379
372
365
359
353
347
341
EXTRA
SECTOR
BYTES
20
o
20
12
5
32
19
36
5
o
21
26
12
20
5
10
35
32
47
30
29
44
22
14
20
40
17
6
7
20
Table 2-1 Sector Select Switch Settings (cont'd)
(Segment 1
= 0)
SECTOR
SWITCH
SETTING
112b14[sf6b181
I~+-+-+--+-+----.
= 0
,
, , ,
SECTORS
2625242322212°
PER
o 1 1 1
101
0111110
0111111
1000000
1000001
1
000
0 1 0
1000011
1000100
1
000
101
1000110
1000111
1001000
100
100
1
1001010
1001011
!
1001100
I
1001101
'
1001110
1001111
1 0 1
000
0
1 0 1
000
1
1 0
100
1 0
1010011
1 0 1 0
100
1 0 1 0
101
1010110
1010111
1011000
1011001
1011010
TRACK
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
2-10
TRACK
= 20,480 BYTES
BYTES
PER
SECTOR
,335
330
325
320
315
310
305
301
296
292
288
284
280
276
273
269
265
262
259
256
252
249
246
243
240
238
235
232
230
227
EXTRA
SECTOR
BYTES
45
20
5
o
5
20
45
12
56
40
32
32
40
56
5
36
75
44
19
o
68
62
62
68
80
12
35
64
10
50
Table 2-1 Sector Select Switch Settings (cont'd)
(Segment 1
= 0)
SECTOR
SWITCH
SETTING
I d2bl41s1617181
L....+--41-+-+-+--+--+-----...
= 0
SECTORS
26252423222'2°
PER
TRACK
1 0 1 1 0 1 1
91
1 0 1 ] 1 0 0 92
1
0 1 1 1 0 1 93
1
0 1 1 1 1 0 94
1 0 1 1 1 1 1 95
1 1
0 0 0 0 0 96
1 1 0 0 0 0 1 97
1 1 0 0 0 1 0 98
1
1 0 0 0 1 1 99
1 1
0 0 1 0 0 100
1
100
101
1100110
1100111
1101000
110 1 001
1101010
1101011
1101100
1101101
1101110
1101111
1110000
1110001
1110010
1110011
1110100
1 1 1 0
101
1110110
1110111
1111000
1111001
1 1 1 1 0 1 0
1111011
1 1 1 1
100
1111101
1111110
1111111
0000000
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
2-11
TRACK
= 20,480
BYTES
BYTES
PER
SECTOR
225
222
220
217
215
213
"'11
L.l
1
208
206
204
202
200
198
196
195
193
191
189
187
186
184
182
181
179
179
176
175
173
172
170
169
167
166
165
163
162
161
160
EXTRA
SECTOR
BYTES
5
56
20
82
55
32
13
96
86
80
78
80
86
96
5
22
43
68
97
20
56
96
27
74
10
64
5
66
12
80
31
106
62
20
105
68
33
o
Table 2-2 Sector Select Switch Settings
(Segment 1
= 1)
SECTOR SWITCH SETTING
112/314151617181
'L+-H-+--+--4--+--
.... = 1
, , , •
1~
I TRACK =
20,480
BYTES
SECTORS
2625242322212°
PER
TRACK
o 0 0 0 0 0 1 1
0000010
2
0000011
3
0000100
4
o 0 0 0
101
5
0000110
6
0000111
7
0001000
8
0001001
9
o 0 0 1 0 1 0
10
0001011
0001100
0001101
0001110
0001111
0010000
o 0
100
0 1
o 0
100
1 0
0010011
o 0 1 0
100
o 0 1 0
101
0010110
0010111
0011000
0011001
0011010
0011011
0011100
0011101
0011110
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
2-12
BYTES
PER
SECTOR
20480
10240
6827
5120
4096
3414
2926
2560
2276
2048
1862
1707
1576
1463
1366
1280
1205
1138
1078
1024
976
931
891
854
820
788
759
732
707
683
LAST
SECTOR
SHORTER
o
o
-1
o
o
-4
-2
o
-4
o
-2
-4
-8
-2
-10
o
-5
-4
-2
o
-16
-2
-13
-16
-20
-8
-13
-16
-23
-10
Table 2-2 Sector Select Switch Settings (cont'd)
(Segment 1
= 1)
SECTOR
SWITCH
SETTING
/1/213141516/718/
I~+-+-+-+-+-~
= 1
,
SECTORS
26252423222'2°
PER
TRACK
0011111
31
o 1 0
000
0 32
o 1 0 0 0 0 1
33
o 1
000
1 0 34
o 1 0 0 0 1 1
35
o 1 0 0 1 0 0
36
o 1 0 0 1 0 1
37
o 1 0 0 1 1 0
38
o 1 0 0 1 1 1
39
o 1 0 1
000
40
010
100
1
0101010
0101011
0101100
0101101
I"
0101110
j
010 1 111
I
0110000
II',
0110001
0110010
0110011
0110100
0110101
I
0110110
I,
0110111
0111000
0111001
0111010
0111011
0111100
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
2-13
TRJ-\CK = 20,480 BYTES
BYTES
PER
SECTOR
661
640
621
603
586
569
554
539
526
512
500
488
477
466
456
446
436
427
418
410
402
394
387
380
373
366
360
354
348
342
LAST
SECTOR
SHORTER
-11
o
-13
-22
-30
-4
-18
-2
-34
o
-20
-16
-31
-24
-40
-36
-12
-16
-2
-20
-16
-8
-31
-40
-35
-16
-40
-52
-52
-40
I
I
I
I
i
I
I
I
,
t
i
~
i
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