Vertex V100 series User manual

...
"V!OO SERIES
OEM/MAINTENANCE
MANUAL
.~
VERTEX
QUIETLYBUILDING THE BEST
Copyright ©1984 Venex Peripherals

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TABLE OF CONTENTS
PAGE
1INTRODUCTION
1.1 GENERAL DESCRIPTION " 1
1.2 SPECIFICATION SUMMARY 2
1.2.1 Physical Specifications 2
1.2.2 Functional Specifications 3
1.2.3 Reliability Specifications 4
1.2.4 Disk Defects 4
2FUNCTIONAL CHARACTERISTICS/OVERVIEW
~.2.1 GENERAL OPERATION 5
2.2 READ/WRITE, SERVO AND CONTROL ELECTRONICS " 5
2.3 DRIVE MECHANISM 6
2.4 AIR FILTRATION SYSTEM ....
.. .. . . .. .. .. . . .. .. .. .. . . .. . .... . .... .. .. 6
2.5 POSITIONING MECHANISM 7
2.6 READ/WRITE HEADS
AND DISKS " 8
2.7 SERVO SYSTEM 8
3FUNCTIONAL OPERATIONS
3.1 POWER SEQUENCING 9
3.2 DRIVE SELECTION
10
3.3 TRACK ACCESSING 10
3.4 HEAD SELECTION 10
3.5 READ OPERATION 10
3.6 WRITE OPERATIONS . .. .. ... .. ....... .... . . . . . . .. .. . .. .. . . .. . . .. . .. . . 11
3.7 SYSTEM INTEGRATION CONSIDERATIONS 11
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4THEORY OF OPERATION
4.1 OVERVIEW " 12
4.2 HEAD-DISK ASSEMBLY 12
4.2.1 Actuator 13_
4.2.2 Recording Media 13
4.2.3 Read/Write Heads _. ........................................ .. 13
4.2.4 Read Preamplifier/Write Driver IC 14
4.2.5 Servo Head 14
4.2.6 Servo Preamplifier IC 15
4.2.7 Spindle Motor 15
4.2.8 Air Filtration Components 15
4.3 SERVO PCB 15
4.3.1 Actuator Lock Driver 15
4.3.2 Clock Generator 15
4.3.3 Spindle Speed Control 16
4.3.4 Spindle Speed Checker 16
4.3.5 Spindle Motor Brake Relay and Relay Driver 16
4.3.6 Actuator Servo Control 16
4.3.7 Demodulator 17
4.3.8 Mode Select Switch 18
4.3.9 Seek Mode " 18
4.3.10 Velocity DAC 18
4.3.11 Tachometer 18
4.3.12 Slope Selector 18
4.3.13 Current Inverter 18
4.3.14 On-Peak Detector - .. 19
4.3.15 Power Amplifier 19
4.3.16 Inverter 19
4.3.17 Track Follow Mode .. , 19
4.3.18 Off-Track Detector 19
4.3.19 Seek Operation 19
4.3.20 Restore to Track 0Operation 20
4.3.21 Power On Reset 20
4.4
DATA PCB 20
4.4.1 Microprocessor and PLA
21
4.4.2 Microprocessor/PLA Control Signals 21
4.4.3 Disk Drive Control Functions 21
4.4.4 Input Buffers 22
4.4.5 Output Drivers ................................................. .. 22
4.4.6 Disk Drive Data Functions 22
4.4.7 Read/Write Data Channel ........................................ .. 22
4.4.8 Head Select and Control Logic 22
4.4.9 Read Chain 23
4.4.10 Amplifier/Signal Conditioner 23
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4.5
4.6
4.7
404.11 Differential Line Driver 23
4.4.12 Write Chain , 23
404.13 Line Receiver 24
404.14 Transition Generator 24
404.15 Write Current Source 24
4.4.16 Write Fault Detector
:. 24
OPERATIONAL SEQUENCE . . . .
.. 24
4.5.1 Power On Reset '
•.... 25
4.5.2 Motor Start 25
4.5.3 Actuator Lock 26
4.5.4 Servo Restore to Track 026
4.5.5 Seek Operation
26
4.5.6 Track Format 28
4.5.6.1 Gap 1 28
4.5.6.2 Gap 2 28
4.5.6.3 Gap 329
4.5.6.4 Gap 4
29
4.5.6.5 Sector Interleaving 29
4.5.7 Read Operation/Head Select
31
4.5.8 Write Operation/Fault Detection 32
ERROR DEFINITION 34
4.6.1 Soft (Recoverable) Errors 34
4.6.2 Hard (Non-Recoverable) Errors 34
4.6.3 Seek (Access Position) Errors 34
DRIVE OPERATION
FLOW CHART 35
5ELECTRICAL INTERFACE
5.1 ELECTRICAL INTERFACE OVERVIEW 39
5.2 CONTROL INPUT LINES 44
5.2.1 Write Gate 44
5.2.2 Head Select 2°,
2', and 22 •••••••••••••••••••••••••••••••••••••• 45
5.2.3 Direction In
45
5.2.4 Step 45
5.2.5 Drive Select
1-4 46
5.3 CONTROL OUTPUT LINES 46
5.3.1 Seek Complete 47
5.3.2 Track 047
5.3.3 Write Fault 47
5.3.4 Index 48
5.3.5 Ready 49
5.4
DATA TRANSFER LINES ;49
504.1 MFM Write Data 50
504.2 MFM Read Data 50
504.3 Read/Write Timing "50
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5.5 DRIVE SELECTED 51
5.6 CUS'fOMER OP'fIONS 51
5.6.1Radial and Select 51
5.6.2 Auto Access 52
5.6.3 Power Sequencing (PS) 52
5.6.4 Non-Multiplexed Index (NMI) 52
5.6.5 Write Protect (WP) 52
5.6.6 Radial Seek Complete (SC) 52
5.6.7 Grounding ' , , 53
6PHYSICAL INTERFACE
6.1 PHYSICAL INTERFACE OVERVIEW 54
6.2
JlIPI CONNEC'fOR-CONTROL SIGNALS 55
6.3 J2/P2 CONNEC'fOR-DATA SIGNALS 55
6.4 J3/P3 CONNEC'fOR-DC POWER 56
6.5
J4/P4 FRAME GROUND CONNEC'fOR 57
6.6 DRIVE PHYSICAL CABLING 58
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7PHYSICAL SPECIFICATIONS
7.1 OVERVIEW 59
7.2 MOUNTING ORIENTATION 59
7.3 MOUNTING HOLES 59
7-.4 PHYSICAL DIMENSIONS 59
7.5 FACEPLATE 61
7.6 SHIPPING REQUIREMENT 61
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8 DATA PCB BLOCK DIAGRAM 63
9SERVO PCB BLOCK DIAGRAM 66
10 MAINTENANCE/REPAIR
10.1 OVERVIEW 69
10.2 REMOVAL OF PARTS NOT REQUIRING ACLEAN ROOM ENVIRONMENT ., 69
10.2.1 Front Cover 69
10.2.2 Side Frames 70
10.2.3 Data PCB 70
10.2.4 Servo PCB 70
10.3 REPAIR AND ADJUSTMENTS 71
10.3.1 Data PCB , , 71
10.3.2 Servo PCB , 71
10.4 SPARE PARTS LIST (MLC l.X) 72
10.5 SPARE PARTS LIST (MLC 2.X) 73
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11 VI00 TEST POINTS (MLC l.X)
11.1 DATA PCB TEST POINTS 74
11.2 SERVO PCB TEST POINTS 78
12 Vl00 TEST POINTS (MLC 2.X)
12.1 DATA PCB TEST POINTS - '" 83
12.2 SERVO PCB TEST POINTS 87
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LIST OF TABLES
PAGE
LIST OF TABLES
5-1 JIIPI CONNECTOR PIN ASSIGNMENT 39
5-2 J2IP2 CONNECTOR PIN ASSIGNMENT 40
5-3 P3-DC CONNECTOR PIN ASSIGNMENTS 40
6-1 DC POWER REQUIREMENTS 56
FIGURES
2-1 AIR FILTRATION SYSTEM 6
2-2
'. READIWRITE HEAD POSITIONING MECHANISM 7
3-1 POWER UP SEQUENCE 9
4-1 POWER RESET 25
4-2 GENERAL SEEK TIMING 27
4-3 "AI" ADDRESS MARK BYTE ........ .. ............................... .. 29
4-4 TYPICAL TRACK FORMAT .. : 30
4-5 TYPICAL READ TIMING 31
4-6 WRITE DATA TIMING 33
5-1 CONTROL SIGNALS 41
5-2 DATA SIGNALS 42
5-3 TYPICAL CONNECTION 4-DRIVE SYSTEM 43
5-4 CONTROL SIGNAL DRIVERIRECEIVER COMBINATION 44
5-5 BUFFERED STEP 46
5-6 INDEX TIMING ...................................................... .. 48
5-7 DATA LINE DRIVERIRECEIVER COMBINATION 49
5-8 READIWRITE DATA TIMING 50
5-9 OPTION SHUNT BLOCK (J6) 51
5-10 PCB OPTION PADS (JI2) 53
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6-1
6-2
6-3
6-4
6-5
6-6
7-1
7-2
8-1
9-1
10-1
10-2
11-1
11-2
11-3
11-4
11-5
11-6
12-1
12-2
12-3
12-4
12-5~
12-6 .
INTERFACE CONNECTOR PHYSICAL LOCATIONS 54
Jl CONNECTOR DIMENSIONS 55
J2 CONNECTOR DIMENSIONS 56
J3 CONNECTOR-INNER PCB SOLDER SIDE 56
TYPICAL & MAXIMUM 12V CURRENT REQUIREMENTS 57
DRIVE INTERNAL AND EXTERNAL CABLING 58
MOUNTING PHYSICAL DIMENSIONS 60
OVERALL PHYSICAL DIMENSIONS 61
DATA PCB BLOCK DIAGRAM 63
SERVO PCB BLOCK DIAGRAM 66
SPARE PARTS LIST/ASSEMBLY (MLC-l.X) 72
SPARE PARTS LIST/ASSEMBLY (MLC-2.X) 73
DATA PCB TEST POINT DESCRIPTIONS 74
TEST POINT OUTPUTS 75
MLC l.X TEST POINT LOCATIONS DATA PCB 77
SERVO PCB TEST POINT DESCRIPTIONS 78
TEST POINT OUTPUT 78
.
MLC l.X TEST POINT LOCATIONS SERVO PCB 82
DATA
PCB TEST POINT DESCRIPTIONS 83
TEST POINT OUTPUTS 84
MCL 2.X TEST POINT LOCATIONS 86
SERVO PCB TEST POINT LOCATIONS 87
TEST POINT OUTPUTS 87
MLC 2.X TEST POINT LOCATIONS 91
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INTRODUCTION
1INTRODUCTION
1.1 General Description
The Vertex VI 00 Family of Disk Drives is aseries of random access storage devices using 2. 3. or 4
nonremovable
51f4 inch disks. Each disk surface employs one movable head to service up to 1166
tracks. Total unfonnatted capacities
of four models are 30.8 (VI30). 51.4 (VI50). 72.0 (VI70). and
85.0 (VI85) megabytes.
Fast access time and high track density are achieved through the use
of arotary voice coil head
positioner
in conjunction with adedicated servo surface.
Th~ inherent simplicity of mechanical construction allows maintenance free operation throughout the
life
of the drive. Both electronic boards are mounted outside the sealed head disk assembly. allowing
field serviceability.
Mechanical and contamination protection for the heads. actuator and disks
is provided by an impact
resistant metal cover. Aself contained re-circulating system supplies clean air through a
0.3 micron
filter. Aseparate filter allows for ambient pressure equalization without introduction
of contami-
nants. Adequate air flow and unifonn temperature distribution throughout the head and disk area are
assured.
The track following servo system allows the heads to continuously follow the recorded track. and
reduces
off track due to non-repetitive spindle run-out. vibration. and environmental temperature
changes: Read and write operations can be perfonned after power up with no thennal stabilization
delay.
Superior data integrity results from the use
of shock isolators. metal film media. ahead landing/
shipping zone. and automatic actuator lock.
The electrical/physical interface is compatible with other available ST412/506 interfaced products.
and includes the same data transfer rate. connectors. DC power. mechanical mounting holes and
package size.

INTRODUCTION
Customer options include:
I. Radial
operation-Outputs active without drive selected.
2. Power On sequencing for multiple drive applications.
3. Non-Multiplexed Index.
4. Write Protect.
5. Radial Seek Complete.
1.2 Specification Summary
1.2.1 Physical Specifications
Power requirements
12 VDC ±10%.
Maximum Ripple 120 mV P-P (a 11.0 VDC Minimum.
P~ak Current 4.5 Amp-Motor Start For 10 Seconds.
Running Current
2.0 Amp avg. (Track Following).
Peak Running Current 2.8 Amp
(~eeking).
Maximum Power Dissipation 54 Watts Peak for 10 Seconds during motor start.
Average Power Dissipation
27 Watts (\2 Volts).
5·VDC ±5%
Maximum Ripple 120 mV P-P @4.88 VDC Minimum.
1.5 Amp avg.lmax.
Average Power Dissipation 7.5 Watts (5 Volts).
Dimensions and Weight
Height* 3.25 in (8.26 cm)
Width* 5.75
in (\4.61 cm)
Depth* 8.00
in (20.32 cm)
Weight 6
Ib (2.72 kg)
*Does not include Faceplate
Environmental Limits
Ambient Temperature
Operating 4°C to 50°C (40°F to 122°F)
Nonoperating
-40°C to 60°C (-40°F to 140°F)
Gradient Less than
10°C (\ 8°F)/hour
2
)
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INTRODUCfION
Relative Humidity
Operating ......................................
.. 8% to 80% (noncondensing)
Operating Maximum Wet Bulb 85°F
Nonoperating ................................... .. 5% to 95% (noncondensing)
Nonoperating Maximum Wet Bulb
85°F-
Shock and Vibration
Operating -2G max, II ms. Half Sine Wave
.010" dA, 2-22 Hz; .25G, 22-6ooHz
Nonoperating 20G max,
II ms. Half Sine Wave
.040" dA, 2-22 Hz; I.OG, 22-6ooHz
Transport 25G's into HDA,
42" Packaged Drop.
Altitude
Operating
-305 m(1000 ft )to +3,000 m (+ 10,000 ft )
Nonoperating
-305 m(1000 ft) to +12,000 m (+40,000 ft)
Acoustical Noise 50 dBa, one meter from cover
1.2.2. Functional Specifications
Storage capacity
VI30 VI50
V 170
VI85
Unformatted* 30.8MB 51.4MB 72.0MB 85.0MB
Formatted (typical sector formats)
:--'(32 x256 bytes) 24.3MB 40.4MB 56.6MB 66.9MB
(17 x512 bytes) 25.8MB 43.0MB 60.1MB 71.0MB
Data tracks
2961 4935 6909 8162
Data Cylinders 987 987 987 1166
Disks 2 3 44
Data Surfaces 35 7 7
Heads, Read/Write 3 5 7 7
Head, Servo I1 1 1
Bytes per Track
Unformatted 10,416
Formatted (typical sector formats)
32 x256 byte sectors 8,192
17 x512 byte sectors 8,704
Maximum Bit Density (bits/inch) 9,897 9,897 9,897 10,526
Maximum Flux Density (flux reversals/inch) 9,897 9,897 9,897 10,526
Track Density (tracks/inch) 960 960 960 1,047
Access time (including settling and transmission
of step pulses)
Track-to-track: 5milliseconds Maximum
Average: 30 milliseconds ±
10%
Maximum: 65 milliseconds
Maximum Average Latency Time: 8.33 milliseconds
3

INTRODUCTION
Rotational Speed: 3600 rotations/minute ±0.1%
Data Transfer Rate: 5megabits/second (625 kilobytes/second)
*Recording Code: Modified Frequency Modulation (MFM)
Interface:
ST4 I 2/506 Compatible
Start Time: Less than
25 seconds
Stop Time: Less than
25 seconds
*NOTE: All models support the use
of 2.7 RLL encoding in addition to MFM. When used with a
controller utilizing RLL encoding. drive capacity may
be expected to increase up to 50%
over the values stated above. Note that error rate criteria may vary depending upon the type
of RLL encoding scheme used.
1.2.3 Reliability Specifications
Mean-time-between-failures (MTBF)
Mean-time-to-repair
(MTIR)
Compdnent life
Error rate
Recoverable Errors
Unrecoverable Errors
,-Seek Errors
1.2.4 Disk Defects
More than 15.000 power on hours
less than 30 minutes
Syears
Iper
10 10 bits read
Iper
10
12
bits read
Iper
lOt> seeks
Disk defects are imperfections
in the media surface. No unit will be shipped if surface analysis
identifies more than 30. 50. 70.
or 85 total defective tracks/drive for the V130. VISO. V170. and
V185 respectively. Note that even at these maximum values. only I%
of the drive capacity is
unavailable. Additionally. no defects will be present on cylinder O. heads O. Iand 2.
Testing for defects involves an analysis
of the total media surface under marginalized test conditions.
Defect information is included on the test data sheet shipped with the drive. and on alabel affixed to
the drive. Format
is cylinder number. head number and bytes from index. Location accuracy is ± 10
bytes.
In asingle format operation. it is probable that errors will not be detected on all of the locations
defined. However. all should be considered defects and flagged by the using system to ensure long
term data reliability.
The use
of an error correction code (ECC) rather than cyclic redundancy check (CRC) is recom-
mended for best data integrity.
4

FUNCfIONAL CHARACTERISTICS
2FUNCTIONAL CHARACTERISTICS/OVERVIEW
2.1 General Operation
The Vl00 Series drives consist of read/write, head positioning and control electronics, rotary voice
coil actuator, media, air filtration system, and disk spin motor.
These components perform the following functions:
1. Interpret and generate control signals.
2. Position and maintain the heads over the desired track.
3. Maintain precise disk rotation speed.
4. Read and write data.
5. Provide acontamination-free environment.
2.2 Read/Write, Servo and Control Electronics
Electronics are packaged on two printed circuit boards. The outennost board, to which control and
data signals are connected, includes:
1. R/W circuits.
2. Interface drivers and receivers.
3. Microprocessor and associated logic.
4. Write fault detection.
5. Drive selection.
6. Optional interface functions.
7. Index circuit.
The second PCB, mounted under the top board, accepts the required
DC voltages and performs the
following functions:
1. Disk spin motor control.
2. Head actuator positioning.
3. Track 0detection.
4.
-10 voltage regulator.
5. Power monitoring.
5

AJNCTIONAL CHARACTERISTICS
2.3 Drive Mechanism
Abrushless 3phase DC drive motor rotates the spindle disk assembly at 3600 rpm. The spindle is
driven directly with no belt
or pulley being used. Acrystal controlled phase lock loop maintains
precise speed regulation. The motor and spindle are dynamically balanced to ensure alow vibration
level. Dynamic braking is used to quickly stop the motor when power is removed. The base plate
assembly is shock mounted to the side mounting frames to minimize transmission
of vibration
through the chassis
or frame. Index signal.is derived from atransducer inside the drive motor.
2.4 Air Filtration System (Figure2·1)
The disks, read/write heads and actuator are fully enclosed in amodule using an integral re-
circulation air system and absolutel:1ter to maintain aclean environment. Aseparate filter permits
ambient pressure equalization without entry
of contaminants.
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ACTUATOR ASSY DISC
Figure 2-1
Air Filtration System
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FUNCfIONAL CHARACTERISTICS
2.5 Positioning Mechanism (Figure 2-2)
The read/write heads and servo head are mounted onto arotary actuator supported by precision ball
bearings. Abobbin-type voice coil mounted between two permanent magnets provides the driving
force required to rotate the actuator for head positioning. Crash stops are provided to protect the head
assemblies should amalfunction cause the actuator to lose control. When the drive is powered down,
the actuator
is driven to ahead landing zone on the inner diameter of the disk. Simultaneously, the
actuator is automatically locked over the landing zone to prevent possible head/media damage when
the drive is subjected to transport shock or movement around the office.
VOICE COIL
MOTOR ASSEMBLY
ACTUATOR YOKE. SPINDLE.
&CRASH STOP ASSEMBLY
Figure 2-2
Read/Write Head Positioning Mechanism
7

RJNCI10NAL CHARACTERISTICS
2.6 Read/Write Heads and Disks
Winchester technology heads and media are used in the VI00 Series disk drives. Maximum record-
ing density is 10,526
flux changes per inch. The heads are connected to the external electronics via a
flat flexible printed circuit cable. Three integrated circuits are mounted on the cable adjacent to the
heads. The circuits provide write curreQt, head selection, and read signal amplification.
Amplification
of the low level rearl signal prior to its leaving the sealed unit provides superior
signal-to-noise ratio and less sensitivity to noise
in the ground system and mounting frame.
2.7 Servo System
Actuator positioning and head track following is accomplished on aclosed loop basis using a
dedicated servo surface. During seek operations, track crossing information is used to optimize
actuator deceleration. A"dual frequency" technique is used. This technique is based on amplitude
differen~es between alternating servo tracks written at two different frequencies. On-track for adata
head is realized when the servo head is positioned exactly between the two servo tracks. Essentially,
the servo head continuously samples the two frequencies, sums and averages the signals, then
positions the head at the point where this averaged signal is
strongest-exactly between the two
tracks. The resultant errorsignal is linearly proportional to the error (off-track) size, and indicates the
off-track direction.
The dual-frequency servo offers several advantages relative to classical di-bit and tri-bit methods:
I. It is relatively insensitive to servo surface media defects. The di-bit/tri-bit methods generally
require an "error-free" servo surface. This reduces manufacturing yields (particularly for high
track density media) and increases the cost
of the servo disk. Since the dual-frequency servo
continuously samples
fA and fB amplitudes, media defects are averaged out and not sensed by the
servo.
2. Because the dual-frequency method uses arelative amplitude difference
of fA and fB frequency,
servo head azimuth alignment is not critical. This alignment is critical in di-bit and tri-bit
methods, however, again raising production costs and increasing service requirements.
3. Since
fA and mfrequencies are recorded well below data frequencies, write data noise is easily
filtered out in the event it is injected into the servo read channel via read/write head to servo head
cross talk.
Track 0is derived from the servo surface information, eliminating the need for aseparate sensor for
this purpose.
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FUNCTIONAL OPERATION
3FUNCTIONAL OPERATIONS
3.1 Power Sequencing (Figure 3-1)
Plus 5and + 12 volts may be applied in any order; however, both voltages must be applied to start the
spindle drive motor. Aspeed sense circuit ensures the spindle is up to speed before recalibrating the
heads to track 0. TRACK 0, SEEK COMPLETE and READY signals on the interface will become
true
~equentially. The drive will not perform read, write or seek functions until READY becomes
true. No commands should be attempted until READY is true. STEP pulses will be ignored, and
WRITE GATE will cause aWRITE
FAULT.
DCON l~
--., I+- 25 SEC. MAX.
DISC UP TO SPEED ] :
. . \l AUTO RECAUBRATE PER'OD
II
'
-TRACK f6 .
I I
-----.1 ~+- 3ms MAXIMUM
-:":SE::-:E-K-::"C-=-OM-P=-L--:"E=-:T E=--------1H ;
I I~I------
III
~~--------.L.I~~! I~ 200 USEC MAX
-READY II
I '-------
I
Figure 3-1
Power Up Sequence
9

RJNCfIONAL OPERATION
3.2 Drive Selection
Drive selection occurs when one of the DRIVE SELECf lines is activated. Only the selected drive
will respond to the input signals, and only that drive's output signals are then gated to the controller
interface (see Section 5.6.1 for exception).
3.3 Track Accessing
Read/write head positioning is accomplished by:
A) Deactivating WRITE GATE.
B) Activating the appropriate DRIVE
SELECf line.
C) Being in the READY condition with SEEK COMPLETE true.
D) Selecting the appropriate DIRECflON IN state.
E) Pulsing the STEP line.
Each step pulse will cause the heads to move either 1track in or 1track out, depending on the level
of
the DIRECflON line. Alow level on the DIRECflON line will cause aseek inward toward the
spindle; ahigh, outward toward track 0.
3.4 Head Selection
Any of the heads can be selected by placing the head's binary address on the three (3) HEAD
SELECf lines:
.......
\
)
DRIVE
V130
VI50
VI70
VI85
NUMBER OF DATA HEADS
3
5
7
7
HEAD ADDRESSES
0, 1,2
0, I, 2, 3, 4
0,
I, 2. 3, 4, 5, 6
0, I, 2, 3,4,5, 6
3.5 Read Operation
Reading data is from the disk and is accomplished by:
A) Deactivating the WRITE GATE line.
B) Activating the appropriate DRIVE
SELECf line.
C) Assuring the drive is READY.
D) Selecting the appropriate HEAD
SELECf levels.
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