SyQuest SQ312RD Installation and operation manual

SQ312RD
OEM
Manual
SyQuest
TECHNO LOGY

TABLE OF CONTENTS
SECTION 1—INTRODUCTION 1
1.1 General Description 1
1.2 Physical Specifications 3
1.3 Reliability Specifications 5
1.*Performance Specifications 5
1.5 Functional Specifications 6
SECTION 2-FUNCTIONAL CHARACTERISTICS . . 7
2.1 General Operation 7
2.2 Read/Write and Control Electronics 7
2.3 Drive Mechanism 8
2.*Door Mechanism/Door Lock Solenoid 8
2.4.1 General Description 8
2.4.2 Opening Sequence Procedure 8
2.5 Positioning Mechanism 9
2.6 Read/Write Heads and Disks 10
2.7 Cartridge Interlock Mechanism 10
SECTION 3-FUNCTIONAL OPERATIONS 15
3.1 Power Sequencing 15
3.2 LED Operation 16
3.2.1 Red 16
3.2.2 Green 16
3.2.3 Orange 16
3.2.4 Slow Flashing Red 16
3.2.5 Rapidly Flashing Red 17
3.3 Drive Selection 17
3.4 Track Accessing 17
3.5 Restore 18
3.5.1 Method 118
3.5.2 Method 218
3.5.3 Method 318
SECTION 4-ELECTRICAL INTERFACE 19
4.1 General Description 19
4.2 Control Input Lines 25
4.2.1 Write Gate 26

TABLE OF CONTENTS (continued)
4.2.2 Head Select 2» 26
4.2.3 Direction In 27
4.2.4. Step 27
4.2.5 Recalibrate 28
4.2.6 Recovery Mode 30
4.2.7 Drive Select 1-4 31
4.2.8 Change Cartridge 31
4.3 Control Output Lines 32
4.3.1 Seek Complete 32
4.3.2 Track 033
4.3.3. Write Fault 33
4.3.4 Index 34
4.3.5 Ready 35
4.3.6 Drive Selected 35
4.3.7 Cartridge In 35
4.3.8 Write Protected 35
4.3.9 Cartridge Changed 36
4.3.10 Radial Index 36
4.4. Data Transfer Lines 36
4.4.1 MFM Write Data 37
4.4.2 MFM Read Data 37
4.4.3 Read/Write Timing 37
4.5 Drive Selected 38
4.6 Option Shunt Block 39
SECTION 5-PHYSICAL INTERFACE 40
5.1 Jl/Pl Connector -Control Signals 41
5.2 J2/P2 Connector -Data Signals 42
5.3 J3/P3 Connector -DC Power 42
SECTION 6—PHYSICAL SPECIFICATIONS 43
6.1 General Description ^3
6.1.1 Mounting Orientation *3
6.1.2 Mounting Holes ^3
6.1.3 Physical Dimensions 43
6.1.4 Air Flow Requirement 4*
6.1.5 Shipping Requirement W

TABLE OF CONTENTS (continued)
SECTION 7—TRACK FORMAT *5
7.1 Gap 150
7.2 Gap 250
7.3 Gap 350
7AGap* 51
7.5 Sector Interleaving 51
7.6 Defective Sector Flags 51
SECTION 8-CARTRIDGE ACCLIMATIZATION .. 52
SECTION 9—CLEANING CARTRIDGE 53
9.1 Materials Required 53
9.2 Procedure 53
9.3 Maintenance 55
SECTION 10 -MOUNTING OPTIONS 56
10.1 General Description Option III 56
10.1.1 Procedure 56
10.2 General Description Option I59
10.2.1 Procedure 60
SECTION 11 -SQ312RD OPTIONS 62
11.1 General Description 62
11.1.1 Write Data Termination 62
11.1.2 Read Data Termination 62
11.1.3 Change Cartridge 62
11.1.* Fault Latch 62
11.1.5 Recovery 62
11.1.6 Recalibrate 63
11.1.7 Auto Recovery Mode 63

LIST OF FIGURES
2-1 Air Filtration System 11
With Switch Locations
2-2 Cartridge Insertion 12
2-3 Cartridge Removal 13
2-* Track Format and Positioning System 1*
4-1 Power-Up Sequence 19
4-2 Control Signals 20
4-3 Data Signals 21
4-4 Typical Connection, 4Drive System 22
4-5 Control Signals 26
Driver/Receiver Combination
4-6 Head Select 28
4-7 Slow Seek Timing 29
4-8 Buffered Seek Timing 29
4-9 Index Timing 34
4-10 Data Line Driver/Receiver Combination .... 36
4-11 Read/Write Data Timings 38
4-12 Option Shunt Block 39
5-1Interface Connector Physical Locations .... 40
5-2 J1Connector Dimensions 41
5-3 32 Connector Dimensions 42
5-4 J3 Connector-Drive PCB Solder Side 42
7-1 Mounting Physical Dimensions 46
7-2 Dimensional View 47
7-3 Track Format As Shipped 48
7-4 "Al" Address Mark Byte 49
9-1C-PAK Instructions 54
10-1Mounting Option Half-Height Option Kit 57
10-2 Mounting Bracket Option Spacing 58
10-3Mounting Bracket Full-Height Option Kit ... 60
11-1Option Jumper 63

LIST OF TABLES
*-l Jl/Pl Connector Pin Asignment 23
*-2 J2/P2 Connector Pin Assignment 2*
*-3 J3/P3 Power Connector Pin Assignment .... 25
7-1 DC Power Requirements V7
7-2 Motor Start Current Requirements £8

SECTION 1
INTRODUCTION
1.1 General Description
The SQ312RD disk drive is arandom access storage
device utilizing removable 100mm disks as storage media.
Each disk surface employs one moveable head to service
615 data tracks. The total formatted capacity of the two
heads and surfaces is 10 megabytes (32 sectors per track,
256 bytes per sector, 122* tracks).
The SQ312RD Model has removable media in the form of
acartridge.
Low cost and unit reliability are achieved through the use
of aband actuator and closed loop stepper head
positioning mechanism. The inherent simplicity of
mechanical construction and electronic controls permits
maintenance free operation throughout the life of the
drive. Both electronic PCB's are mounted outside the
head disk assembly.
Mechanical and contamination protection for the heads,
actuator, and disks is provided by an impact resistant
aluminum enclosure. Aself-contained recirculation
system supplies clean air through a0.3 micron filter. The
spindle and disk act as apump, assuring adequate air flow
and uniform temperature distribution throughout the head
and disk area. The on-board microcomputer does thermal
compensation during power-up. This provides signi-
ficantly greater off track margin and the ability to
immediately perform read and write operations after
power-up with no thermal stabilization delay.
The SQ312RD electrical interface is identical to the pin-
out, data transfer rates, and track/sector formats as
the Seagate ST506/412 or equivalent and insures full

compatibility with awide host of 5ft" Winchester disk
drive controllers. The half-size form factor (half-height)
design allows two SQ312RD drives to fit within the space
of one 5V floppy Winchester envelope, and the DC power
requirements and connector for the SQ312RD are the
same as for the industry standard 5H" Winchester. No AC
power is required.
Key Features
•12.75 Mbyte storage capacity.
•Half-height minifloppy form factor.
•Removable cartridge media that requires no purge
cycle upon power-up.
•Buffered seek mode for faster data access.
•Closed-loop servo system with imbedded digital
servo for full cartridge interchangeability between
any SQ312RD drive.
•Same interface and track format as standard 5J4"
Winchester.
•Utilizes existing 5J4" Winchester controllers.
•Ruggedized for portable systems.
•Same DC voltages and current as the minifloppy.
•Band actuator and .9° stepper motor head
positioning mechanism.
•Data Recovery Mode.
Solenoid controlled door lock.

1.2 Physical Specifications
ENVIRONMENTAL LIMITS
Ambient Temperature:
(operating)
(non-operating)
Maximum Temperature:
Gradient:
(operating)
(non-operating)
Relative Humidity
Maximum Elevation:
(operating)
(non-operating)
Shock:
(operating)
(non-operating)
Vibration:
(operating)
40° to 122°F
(*o to 50°C)
-1*° to 140F
(-10° to 60°C)
18°F/Hr. (10°C)
Below Condensation
8to 80 percent
(non-condensing)
10,000 feet
-1,000 to 35,000 feet
lOG's, 1 1 msec, half sine
40G's, 11msec, half sine
(in shipping container)
2to 10 Hz
0.10" Double Amplitude
10 to 500 Hz
0.5G Peak to Peak

ENVIRONMENTAL LIMITS (continued)
Vibration:
(non-operating)
DC Power Requirements
2to 10 Hz
0.40" Double Amplitude
10 to 500 Hz
2.0G Peak to Peak
+12V +5% (§ .9 amps
(50 mv P-P max. ripple)
+5V +5% @.9 amps
(50 mv P-P max. ripple)
MECHANICAL DIMENSIONS
Height 1.63 inches
Width 4.8 inches
Depth 8.0 inches
Weight 2A lbs.
Shipping Weight 4.3 lbs.
CARTRIDGE MECHANICAL DIMENSIONS
Height 0.43 inches
Width 4.33 inches
Length 4.4 1inches
Weight 0.3 lbs.
HEAT DISSIPATION
13K
2watts (46BTU/Hr) Maximum

1.3 Reliability Specifications
MTBF
PM
MTTR
Component Design Life
11,000 POH, typical usage
Not Required
30 minutes
5Years
Error Rates:
Soft read errors
Hard read errors
Seek errors
1per 10^ bits read
1per 10*2 bits read
.... 1per 106 seek
NOTE: Error rate performance achieved with an
available MFM data window of better than
80 nsec.
1.4 Performance Specifications
Capacity (Unformatted)
Per Drive 12.76 Megabytes
Per Surface 6.38 Megabytes
Per Track 10417 Bytes
Capacity (Formatted)
Per Drive 10.0 Megabytes
Per Surface 5.0 Megabytes
Per Track 8192 Bytes
Per Sector 256 Bytes
Sectors Per Track 32
Transfer Rate 5.0 Mbits/sec

Access Time (Includes Setting)
One Track
Average*
Maximum*
Average Latency
45 (typical)
135 (typical)
250 (typical)
...8.46 ms
1.5 Functional Specifications
Rotational Speed 335 rpm +1%
Recording Density 12,608 bpi max
Flux Density 12,608 fci
Track Density 74 1tpi
Cylinders 615
Track,s1230
Read/Write Heads 2
Disks ][\ 1
Index 1
Access Times
To guarantee 100% interchangeability of cartridges
between drives, the SQ312RD Model uses aunique
imbedded digital servo scheme (Digilok™). This results in a
variance of access times which insures the customers'
data integrity.
Both heads have servo in the index burst which remains
transparent to the user. A1.25 MHZ signal is injected in
the Read Data stream during the period the micro-
processor is sampling the servo information and, thus,
eliminates any lock-up problems which may occur in
certain controllers.
*Using Buffered Seek

SECTION 2
FUNCTIONAL CHARACTERISTICS
2.1 General Operation
The SQ312RD disk drive consists of read/write, servo and
control electronics, read/write heads, track positioning
actuator, and air filtration system. The Model SQ312RD
also has acartridge interlock mechanism. The compon-
ents perform the following functions:
1. Interpret and generate control signals.
2. Position the heads over the desired track.
3. Read and write data.
4. Provide interchangeability between SQ200 car-
tridges.
2.2 Read/Write and Control Electronics
Electronics are packaged on two printed circuit boards.
The primary board to which power, control and data
signals are connected includes:
1. Index detection circuit.
2. Head position/actuator circuit.
3. Read/write circuits.
k. Drive speed detector.
5. Head select circuit.
6. Write fault detection circuits.
7. Servo decoder and control.
8. Stepper motor drive circuit.
9. Drive select circuit.
10. Track zero detector.

The second PCB, mounted at the rear of the drive, derives
its power from the primary board and provides power and
speed control to the spindle drive motor and the solenoid
interlock mechanism.
2.3 Drive Mechanism
The brushless DC drive motor rotates the spindle at 3545
rpm. The spindle is driven directly with no belt or pulley
being used. The motor and spindle are dynamically
balanced to insure alow vibration level. Dynamic braking
is used to quickly stop the spindle motor when power is
removed. The head/disk assembly is shock mounted to
minimize transmission of vibration through the chasis or
frame.
2.4 Door Mechanism/Door Lock Solenoid
2.4.1 General Description
The door lock solenoid feature of the SQ312RD disk
drive, disengages power to the spindle motor and
allows mechanical removal of the cartridge media.
This prevents media and/or head damage, but allows
removal of the cartridge media even in apower off
situation, insuring data security. Figure 2-1 shows
the door lock solenoid position in relation to the disk
drive. The door mechanism is shown in Figure 2-3.
2.4.2 Opening Sequence Procedure
1. Depress the front panel switch. This cuts off
12 volt power to the spindle motor while the
microprocessor moves the heads to track 20
position and removes power to the stepper
motor.

2. Wait until the front panel LED stops flashing
and depress the front panel switch fully until
the front door automatically opens partially.
Manually open the door to aright angle
position with the front opening. The carriage
then moves to retract position at the outer
diameter. The heads unload and the cartridge
is lifted off the spindle by the cartridge
guides.
3. Depress the front door open fully and the
cartridge ejects. Note: The front door will
return to right angle position when pressure is
released.
NOTE: Door should be closed at all times with the
exception of cartridge insertion or removal.
Air Filtration System
The disks and read/write heads are fully enclosed in a
module using an integral recirculation air system and
absolute filter to maintain aclean environment. The
total air volume of the drive and cartridge is purged
through the absolute filter once per second.
2.5 Positioning Mechanism
The read/write heads are mounted on aball bearing
supported carriage which is positioned by aband actuator
connected to the stepper motor shaft. The drive uses a
microstepping stepper positioner which steps at 0.9
degrees per step. The closed-loop imbedded servo control
design extends the accuracy of the SQ312RD metal band
positioner to 20 microinches. The imbedded burst servo

scheme, where servo control data resides within asingle
wedge per track, affords users full definition control of
sector formats.
2.6 Read/Write Heads and Disks
The recording media consists of asingle, 100mm "thin
film" metallic alloy platter. The glass-like carbon over-
coat that protects the magnetic substrate makes the thin
film disks impervious to environmental contaminants such
as dust, smoke particles, and ambient humidity. The
carbon overcoat also eliminates the need for extended
purge cycles; and coupled with the low load force/low
mass flying heads, permits reliable contact start/stop
operation and exceedingly high durability.
Data on each of the two disk surfaces is read by a
read/write head, each of which accesses 615 tracks. The
SQ312RD utilizes industry standard composite heads.
2.7 Cartridge Interlock Mechanism
The fail-safe cartridge interlock mechanism ensures
procedural compliance by users as the cartridge is only
permitted to be inserted in the appropriate position. The
interlock mechanism disengages the composite heads from
the media upon opening the front door.

ax FRONT
DOOR
SWITCH
FIGURE 2-1
AIR FILTRATION SYSTEM WITH SWITCH LOCATIONS

PRESSURE SHOULD BE
APPLIED TO THIS REGION
FOR ENGAGEMENT
CARTRIDGE (Q-PAK)
WRITE PROTECT TAB
FRONT DOOR
FRONT PANEL SWITCH (GRET)
FIGURE 2-2
CARTRIDGE INSERTION

DOOR CLOSED PUSH FRONT PANEL SWITCH
TO OPEN
DOOR PARTIALLY OPENED BY
SPRING DETENT
DOOR OPENED MANUALLY
DOOR IS PARALLEL WITH
DRIVE FOR INSERTION:
SLIGHTLY BEYOND
PARALLEL FOR EJECTION
FIGURE 2-3
CARTRIDGE REMOVAL