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Seagate ST11200ND, ST1980ND, ST1980NC, ST11200NC, ST11200N User Manual

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Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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Hawk 1 Family
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ST11200N/ND/NC
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ST1980N/ND/NC
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ST1830N, ST1950N
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Product Manual
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Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hawk 1 Family
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ST11200N/ND/NC
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ST1980N/ND/NC
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ST1830N, ST1950N
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Product Manual
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Copyright Notice
© 1994 Seagate Technology, Inc. All rights reserved Publication Number: 77738476, Rev. D June 1994
Seagate, Seagate Technology, Wren and the Seagate logo are registered trademarks of Seagate Technology, Inc. SeaFAXTM, SeaFoneTM, SeaTDDTM and SeaBOARDTM are trademarks of Seagate T echnol­ogy, Inc. Other product names are registered trademarks or trademarks of their owners.
Seagate reserves the right to change, without notice, product offerings or specifications. No part of this publication may be reproduced in any form without written permission of Seagate Technology, Inc.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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Revision status summary sheet
Revision Authority Date Writer/Eng. Sheets Affected
A Issue 1/12/93 D. Ashby 1 through 72
B. Norman
B PLD: 83287 3/12/93 D. Ashby 1 through 70.
B. Douglas (Technical changes on pages 17 thru
20, 38, 39, 41 thru 43, and 68). C PLD: 83504 93 Oct 04 D. Ashby v thru vii, 1 thru 73 D PLD: 83684 94 Jun 13 D. Ashby v thru viii, 1 thru 73
(technical changes on pages 3, 8, 14,
27, 49, 57, 59)
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Notice:
Product Manual 77738476 is Volume 1 of a two Volume document with the SCSI interface informa­tion in the Volume 2 SCSI Interface Product Manual, P/N 77738479.
If the SCSI Interface information is needed the Volume 2 Interface Manual should be ordered, P/N
77738479.
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1.0 Scope ..................................................................................................................................... 1
2.0 Applicable standards and reference documentation........................................................... 2
2.1 Standards ..................................................................................................................... 2
2.2 Applicable reference documents .................................................................................. 3
3.0 General description................................................................................................................. 4
4.0 Standards features .................................................................................................................. 6
4.1 Performance................................................................................................................. 6
4.1.1 Reliability ......................................................................................................... 6
4.2 Unformatted and formatted capacities.......................................................................... 7
4.3 Options (factory installed)............................................................................................. 7
4.4 Optional accessories (user installed)............................................................................ 7
4.5 Installation .................................................................................................................... 8
5.0 Performance characteristics .................................................................................................. 9
5.1 Internal drive characteristics (transparent to user) ....................................................... 9
5.2 SCSI drive Seek, Read and Write performance characteristics (Visible to User)......... 9
5.2.1 Seek command execution time........................................................................ 9
5.2.2 Format drive command execution time............................................................ 10
5.2.3 Read data command execution time ...............................................................10
5.2.4 Write data command execution time................................................................10
5.3 Generalized performance characteristics.....................................................................10
5.4 Start/stop time ..............................................................................................................13
5.5 Prefetch/multi segmented cache control....................................................................... 13
5.5.1 Cache operation .............................................................................................. 13
5.5.2 Prefetch operation ........................................................................................... 14
5.6 Caching write data........................................................................................................ 15
5.7 Synchronized spindle operation.................................................................................... 15
T a b le of contents
6.0 Reliability specifications ........................................................................................................19
6.1 Error rates ....................................................................................................................19
6.1.1 Read errors...................................................................................................... 19
6.1.2 Environmental interference..............................................................................19
6.1.3 Write errors ...................................................................................................... 20
6.1.4 Seek errors ...................................................................................................... 20
6.2 Reliability and service................................................................................................... 20
6.2.1 Mean time between failure............................................................................... 20
6.2.2 Preventive maintenance ..................................................................................20
6.2.3 Service life ....................................................................................................... 20
6.2.4 Service philosophy...........................................................................................21
6.2.5 Installation........................................................................................................21
6.2.6 Service tools .................................................................................................... 21
6.2.7 Product Warranty............................................................................................. 21
7.0 Physical/electrical specifications ..........................................................................................22
7.1 AC power requirements................................................................................................ 22
7.2 DC power requirements................................................................................................22
7.2.1 Conducted noise immunity .............................................................................. 23
7.2.2 Power sequencing ...........................................................................................23
7.2.3 12 V - current profile ........................................................................................23
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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T a b le of contents
7.3 Heat/power dissipation ................................................................................................. 24
7.4 Environmental limits .....................................................................................................25
7.4.1 T emper ature.....................................................................................................25
7.4.2 Relative humidity ............................................................................................. 27
7.4.3 Effective altitude (sea level ref)........................................................................27
7.4.4 Shock and vibration .........................................................................................27
7.4.5 Air cleanliness ................................................................................................. 29
7.5 Electromagnetic compatibility.......................................................................................29
7.5.1 Electromagnetic susceptibility..........................................................................29
7.6 Mechanical specifications............................................................................................. 30
7.6.1 Drive orientation...............................................................................................32
7.6.2 Cooling.............................................................................................................32
7.6.3 Drive mounting.................................................................................................32
8.0 Media characteristics.............................................................................................................. 33
8.1 Media description .........................................................................................................33
9.0 Defect and error management ...............................................................................................34
9.1 Drive internal defects/errors .........................................................................................34
9.2 SCSI systems error considerations .............................................................................. 34
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10.0 Option/configuration headers ................................................................................................ 35
10.1 Drive ID/option select header .......................................................................................35
10.2 Synchronized spindles interface...................................................................................39
10.2.1 electrical description ........................................................................................ 39
10.3 Grounding.....................................................................................................................40
11.0 Interface requirement.............................................................................................................. 41
11.1 General description ...................................................................................................... 41
11.2 SCSI interface messages supported ............................................................................ 41
11.3 SCSI interface commands supported ........................................................................... 42
11.3.1 Inquiry data......................................................................................................44
11.3.2 Mode sense data .............................................................................................45
11.4 SCSI bus conditions and miscellaneous features supported........................................ 53
11.5 Synchronous data transfer ........................................................................................... 54
11.5.1 Synchronous data transfer periods supported.................................................54
11.5.2 REQ/ACK offset............................................................................................... 54
11.6 Physical interface ......................................................................................................... 55
11.6.1 DC cable and connector .................................................................................. 56
11.6.2 Physical characteristics ...................................................................................56
11.6.3 Connector requirements ..................................................................................57
11.6.4 Electrical description........................................................................................ 63
11.7 Disc drive timing ...........................................................................................................67
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12.0 Options..................................................................................................................................... 69
12.1 Front panel ................................................................................................................... 69
12.2 Single unit shipping pack .............................................................................................. 69
12.3 Drive termination .......................................................................................................... 69
13.0 Accessories .............................................................................................................................70
13.1 Front panel kit...............................................................................................................70
13.2 Installation manual........................................................................................................ 70
14.0 Technical support services .................................................................................................... 71
Seagate Peripheral Family................................................................................................................... 72
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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1.0 Scope
This specification describes the Seagate Technology, Inc. Model Hawk 1 Family Disc Drives. These high capacity, high performance disc drive products have been designed to support the Small Computer Sys­tems Interface (SCSI) and are classified as “Intelligent” peripherals. The Model Hawk 1 Family is function­ally compatible to a subset of the Seagate SCSI-2 Interface Specification 77738479, and the ANSI SCSI-2 standard. The Hawk 1 Family also provides Level 2 conformance (highest level) with the ANSI SCSI-1 standard. Details of the Ha wk 1 Family drive SCSI implementation are provided in Section 11 of this speci­fication, (Vol. 1) and in the SCSI-2 Interface Product Manual P/N 77738479 (Vol. 2; Ver. 2).
The Hawk 1 family of drives consists of the ST11200N/ND/NC, ST1980N/ND/NC , ST1950N and ST1830N drives.
The Hawk 1 Family products will be referred to as “the drive” from this point on unless reference to individual models are necessary.
The drive printed circuit board is referred to as a PCB.
1
SEAGATE
*
* 50 pin SCSI I/O and 4 pin DC power connector shown. "NC" models have one 80 pin connector and no
separate DC power connector.
Figure 1-1. Hawk 1 N/ND family drive
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2.0 Applicable standards and reference documentation
The drive has been developed as a system peripheral to the highest standards of design and construction. The drive depends upon its host equipment to provide adequate power and environment in order to achieve optimum performance and compliance with applicable industry and governmental regulations. Special at­tention must be given in the areas of safety, power distribution, shielding, audible noise control, and tem­perature regulation.
2.1 Standards
The Hawk 1 Family complies with Seagate standards as noted in the appropriate sections of this specifica­tion and the Seagate SCSI-2 Interface Specification, P/N 77738479 (Vol. 2, Version 2).
The Hawk 1 Family is a UL Recognized component per UL 1950 and a CSA Certified component per CAN/ CSA-C22.2 No. 950-M89. It also meets the requirements of DIN VDE 0805/05.90 and EN60950: 1988 (IEC
950). The Hawk 1 family drives, as delivered, are designed for system integration and installation into a suitable
enclosure prior to use. As such the Ha wk 1 f amily drives are supplied as a sub-assembly and is not subject to Subpart J of Part 15 of the FCC Rules and Regulations nor the Radio Interference Regulations of the Canadian Department of Communications. However, the unit has been tested using proper shielding and grounding and found to be compliant with Class A limits of the FCC Rules and the Regulations of The Canadian Department of Communications.
The physical design characteristics of the Hawk 1 family drives serve to minimize radiation when installed in an enclosure that provides reasonable shielding. As such, the Ha wk 1 f amily drives are capab le of meeting the Class B limits of the FCC Rules and Regulations of the Canadian Department of Communication. How­ever , it is the users responsibility to assure that the Ha wk 1 f amily drives meet the appropriate EMI require­ments in their system. Shielded I/O cables may be required if the enclosure does not provide adequate shielding. If the I/O cables are external to the enclosure, shielded cables should be used, with the shields grounded to the enclosure and to the host controller.
Caution. To avoid potential service problems, observe the following precautions:
The Manufacturers installed labels must not be removed from the drive or covered with addi­tional labels, as they contain information required when servicing the product.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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2.2. Applicable reference documents
SCSI Installation Handbook Seagate P/N 77738480 Product Manual - SCSI-2 Interface Seagate P/N 77738479 ANSI Small Computer System Interface (SCSI): Document Number ANSI3.131-1986 (X3T9/84.40 Rev. 1B) (X3T9.2/82-2 Rev. 17B) and X3T9.2/86-109 Revision 10C (SCSI-2).
Package Test Specification: Seagate P/N 30190-001 (under 100 lb) Package Test Specification: Seagate P/N 30191-001 (over 100 lb.)
In case of conflict between this document and any referenced document, this document shall take prece­dence.
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3.0 General description
The drives are a member of a family of low cost, high performance, highly reliable, random access storage devices designed to meet the needs of the OEM marketplace.
The drive records and recovers data on eight 3.7 inch (95 mm) fixed discs. The drive supports the Small Computer System Interface-2 (SCSI-2) as described in the ANSI SCSI and
SCSI-2 Interface Specifications to the extent described in this product specification (Vol. 1), which defines the product performance characteristics of the Hawk 1 N/ND Family of drives, and the SCSI-2 Interface Product Manual P/N 77738479 (Vol. 2, Version 2) which describes the general interface characteristics of this and other families of Seagate 3.5-inch drives.
The drive interface supports multiple initiators, disconnect/reconnect, self configuring host software and automatic features that relieve the host from the necessity of knowing the physical characteristics of the target (logical block addressing is used).
The Head/Disc Assembly (HDA) is environmentally sealed at the factor y. Air recirculates within the HDA through a nonreplaceable filter to maintain a contamination free head/disc environment.
Refer to Figure 3.0-1 for an exploded view of the drive. NEVER disassemble the Head/Disc Assembly (HDA). This exploded vie w is for inf ormation only . Do not attempt to service items in the sealed environmen­tal enclosure (heads, media, actuator, etc.) as this requires special facilities. The drive contains no parts replaceable by the user. The drive warranty is voided if the HDA is opened.
The Hawk 1 Family drives use a dedicated landing zone at the innermost radius of the media to eliminate the possibility of destroying or degrading data by landing in the data zone. The drive automatically goes to the landing zone when the power is removed.
The Hawk 1 Family drives incorporate an automatic shipping lock which prevents potential damage to the heads and discs resulting from movement during shipping and handling. The shipping lock disengages when power is applied to the drive and the head load process begins.
The Hawk 1 F amily drives decode Track 0 location from the dedicated servo surface to eliminate mechani­cal transducer adjustments and related reliability concerns.
The Hawk 1 Family drives use a high performance actuator assembly that consists of a low inertia, bal­anced, patented, straight arm design that provides excellent performance with minimum power dissipation.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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N/ND Family PCB NC Family PCB
Figure 3.0-1. Hawk 1 family drive
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4.0 Standard features
The Hawk 1 Family has the following standard features:
• Integrated SCSI Controller
• Single Ended and Diff erential SCSI driv ers and receivers
• Asynchronous and Synchronous data transfer protocol
• Firmware downloadable via SCSI interface
• Selectable sector size from 256 to 4096 bytes/sector
• Programmable sector reallocation scheme
• Flawed sector reallocation at format time
• Programmable auto write and read reallocation
• Reallocation of defects on command (Post Format)
· 96 bit Reed-Solomon error correcting code
• Sealed Head/Disc Assembly
• No preventative maintenance or adjustment required
• Dedicated head landing zone
• Automatic shipping lock
• A utomatic Thermal Compensation
• Patented Tri-Phase Servo with embedded Grey Code track address to guarantee servo positioning.
• Self diagnostics performed at power on
• 1:1 Interleave
• Zoned Bit Recording (ZBR)
• Vertical, horizontal, or top down mounting
• Dynamic spindle brake
• Active termination with removable terminator modules.
• Synchronous spindle capability
• 256 K byte data buffer
• 5-year warranty
4.1 Performance
• Programmable multi-segmentable cache buffer
• A utomatic Adaptive Cache
• Zero Latency Reads
• 5411 RPM Spindle. Average latency = 5.4 ms
• Command Queuing of up to 64 commands per initiator
• Background processing of queue
• Supports start and stop commands
• Provides synchronized spindle capability
• Low audib le noise for office environment
• Low power consumption
• Balanced low mass rotary voice coil actuator
4.1.1 Reliability
• 200,000 hour MTBF
• Adaptive servo compensation for improved seek performance
• LSI circuitry
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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4.2 Unformatted and formatted capacities
Formatted capacity depends on the number of spare reallocation sectors reserved and the number of bytes per sector. The following table shows some typical formatted capacities.
Capacities in Megabytes Applicable model numbers
Spare Sector or Cylinders ST11200 ST1980 ST1950 ST1830 reserved for reallocation 512* 1024* 512* 1024* 512* 1024* 512* 1024* No Spares 1066 1116 872 913 814 852 712 747 One Spare Sector per track/2 spare cylinders per unit** 1051 1087 860 8 89 803 831 702 728 One Spare Sector per cylinder; 2 spare cylinder per unit** 1064 1114 870 910 812 850 711 745 Unformatted Capacity 1248 1021 953 834
*Bytes per sector. Sector size selectable at format time. Users having the necessar y equipment may modify the data block size before issuing a f ormat command and obtain different f ormatted capacities than those listed. User available capacity depends on spare reallocation scheme selected. See Mode Select Command and Format Command in the SCSI Interface Product Manual P/N 77738479.
**Spare cylinders are on the inner tracks.
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The standard OEM model is as follows:
Formatted Data Block Size Unformatted 512 Byte/Sector
ST11200N/ND/NC 1054 MB* 1248 MB ST1980N/ND 860 MB** 1021 MB ST1950N 803 MB** 953 MB ST1830N 702 MB** 834 MB
* Twelve spare sectors per cylinder, two spare cylinders/unit. ** One spare sector per track, two spare cylinders/unit.
4.3 Options (factory installed)
The capacities shown in paragraph 4.2 are available upon request. Other capacities can be ordered de­pending on sparing scheme and sector size requested.
The following options are incorporated at the time of production. See Section 12.0.
• Front panel (green LED) - See Figure 3.0-1
• Installation Manual P/N 77738480
• SCSI Interf ace Terminating Resistors (Single Ended only)
4.4 Optional accessories (user installed)
The following accessories are available. All kits may be installed in the field. See Section 13.0.
• Front Panel Kit (with green LED) - See Figure 3.0-1
• Single Unit shipping pack kit
• Installation Guide P/N 77738480
•· Adapter Accessory Frame Kit P/N 75790701 (adapts 3.5-inch drive to fit in 5.25-inch drive mounting
space)
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4.5 Installation
For option jumper locations and definitions refer to Figure 10.1-1. Drive default mode parameters are not normally needed for installation. Ref er to Section 11.3.2 for default mode parameters if they are needed.
• Ensure that the SCSI ID of the drive is not the same as the host adapter. Most host adapters use
SCSI ID 7.
• If multiple devices are on the bus set the drive SCSI ID to one that is not presently used by other
devices on the bus.
• If the drive is the only device on the bus, attach it to the end of the SCSI bus cable. Terminators are
required either on the drive for ST11200N and ST11200NC f amily models, or external to the drive for ST11200ND family models. These external terminators must be provided by the user, systems integrator or host equipment manufacturer.
• If the drive is attached to a bus that contains other devices, and the new drive is not attached to the
end of the bus, the terminators should be removed from the new drive.
• Set all appropriate option jumpers for desired operation prior to power on. If jumpers are changed
after power has been applied, recycle the drive power to make the new settings effective.
• Installation instructions are provided by host system documentation or with any additionally pur-
chased drive installation software. If necessary see section 14.0 for Seagate support services telephone numbers.
Formatting
• It is not necessary to low level format this drive. The drive is shipped from the factory low level
formatted in 512 byte sectors.
· Reformat the drive if one of the following occurs.
-A different sector size is selected.
-A different spare sector allocation scheme is selected.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
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5.0 Performance characteristics
5.1 Internal drive characteristics (transparent to user)
ST11200 ST1980 ST1950 ST1830
Drive Capacity 1248 1021 953 834 MByte (UNF) Read/Write Heads 15 13 13 13 Data (Max) Bytes/Track 41660 45434 46550 48419 Bytes (Avg) Bytes/Surface 83 78.5 73 64 Mbytes (UNF) Tracks/Surface, Total 1872 1730 1575 1325 Tracks (user
accessible) Tracks/Inch 2150 2150 2150 2150 TPI Servo Heads 1111 Internal Data Rate 23.2-40.6 24.4 - 40.6 25.2-41.2 28.4-41.2Mbits/sec
(variable with
zone) Disc Rotational Speed 5411 +0.5% 5411 + 0.5% 4535 +0..5% 4535 +0.5% r/min Average Rotational Latency 5.54 5.54 6.61 6.61 ms
5.2 SCSI Seek, Read and Write performance characteristics [8]*
Refer to Section 11.7 and to the SCSI-2 Interface Product Manual 77738479 f or additional timing details .
5.2.1 Seek time
Drive Level ST11200 ST1980 ST1950 ST1830 Read Write Read Write Read Write Read Write
ms ms ms ms
Average - Typical [3] 10.5 11.2 9.9 10.6 TBD TBD TBD TBD
Max. [2] 12.0 13.0 11.4 12.4 TBD TBD TBD TBD
Single Track- Typical [3] 1.5 2.0 1.5 2. 0 TBD TBD TBD TBD
Max. [2] 3.5 4.0 3.5 4.0 TBD TBD TBD TBD
Full Stroke - Typical [3] 20.0 21.0 19.0 20.0 TBD TBD TBD TBD
Max. [2] 23.5 24.5 22.5 23.5 TBD TBD TBD TBD
Including Controller Overhead** [1][4] ST11200 ST1980 ST1950 ST1830 Read Write Read Write Read Write Read Write
ms ms ms ms
Average - Typical [3] 11.7 12.5 11.1 11.9 TBD TBD TBD TBD
Max. [2] 14.0 15.0 13.4 14.4 TBD TBD TBD TBD
Single Track - Typical [3] 2.6 3.3 2.6 3.3 TBD TBD TBD TBD
Max. [2] 5.5 5.9 5.5 5.9 TBD TBD TBD TBD
Full Stroke - Typical [ 3 ] 21.2 22.4 20.2 21.4 TBD TBD TBD TBD
Max. [2] 25.7 27.1 24.7 26.1 TBD TBD TBD TBD
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5.2.2 Format drive command execution time (minutes) [1]
Maximum (with verify) 30 min 28 min TBD TBD Maximum (no verify) 20 min 18 min TBD TBD
* [ ] All notes are listed in Section 5.3.1. ** With disconnect enabled and Read Look Ahead cache disab led.
5.2.3 Read data command execution time [4]*
(512 byte sector size, with disconnect enabled and read look ahead cache disabled) latency time is included.
a. From CDB reception to the drive request for the first data byte to be transferred to the Host
1. Typical (Zero Stroke Seek) [3] 7.2 ms 7.2 ms TBD TBD
2. Typical (Average Seek) [3] 17.5 ms 16.8 ms TBD TBD
3. Maximum (Full Stroke Seek) [2] 36.1 ms 35.1 ms TBD TBD
b. Single Sector Read and Transfer of data to Host (time from receipt of last byte of the CDB to the request
for a status byte transfer to Host) [7].
ST11200 ST1980 ST1950 ST1830
ST11200 ST1980 ST1950 ST1830
ST11200 ST1980 ST1950 ST1830
1. Typical (Zero Stroke Seek)[3] 7.3 7.3 ms TBD TBD
2. T ypical (Aver age Seek)[3] 17.6 ms 16.9 ms TBD TBD
3. Maximum (Full Stroke Seek)[2] 36.2 ms 35.2 ms TBD TBD
5.2.4 Write data command execution time [4]
(512 byte sector size, with disconnect disabled and read look ahead disabled) latency time is included.
a. From CDB reception to the request for the first byte of write data from the Host.
1. Typical 1.5 ms 2. Maximum 1.8 ms
b. Single Sector Write and Data Transfer from Host [6] [7]
(Time from receipt of the last byte of the CDB to the request for a completion status transf er to the Host)
ST11200 ST1980 ST1950 ST1830
1. Typical (Zero Stroke Seek)[3] 7.0 ms 7.0 ms TBD TBD
2. T ypical (Aver age Seek)[3] 18.2 ms 17.6 ms TBD TBD
3. Maximum (Full Stroke Seek)[2] 38.2 ms 37.2 ms TBD TBD
*[ ] All notes are listed in Section 5.3.1.
5.3 Generalized performance characteristics
Minimum Sector Interleave 1 to 1 Data Buffer To/From Disc Media
Data transfer rate (< 1 sector) - 512 Byte Sector
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continued from previous page
ST11200 ST1980 ST1950 ST1830
Min. [4]* 2.90 3.05 TBD TBD MByte/sec Avg. [4] 4.14 4.21 Max. [4] 5.07 5.07
Data Buffer To/From Disc Media
Data Transfer Rate (< 1 Track) - 512 Byte Sector
ST11200
Min. [4] 2.50 MByte/sec divided by (Interleave Factor) Avg. [4] 3.55 MByte/sec divided by (Interleave Factor) Max. [4] 4.36 Mbyte/sec divided by (Interleave Factor)
ST1980
Min. [4] 2.62 MByte/sec divided by (Interleave Factor) Avg. [4] 3.61 MByte/sec divided by (Interleave Factor) Max. [4] 4.36 MByte/sec divided by (Interleave Factor)
ST1950
Min. [4] TBD MByte/sec divided by (Interleave Factor) Avg. [4] TBD MByte/sec divided by (Interleave Factor) Max. [4] TBD Mbyte/sec divided by (Interleave Factor)
ST1830
Min. [4] TBD MByte/sec divided by (Interleave Factor) Avg. [4] TBD MByte/sec divided by (Interleave Factor) Max. [4] TBD MByte/sec divided by (Interleave Factor)
SCSI Interface Data Transfer Rate (Asynchronous) [5]
ST11200 ST1980 ST1950 ST1830
-Maximum Instantaneous 5.0** 5.0 TBD TBD MBytes/sec**
-Maximum Aver age 3.1 3.1 TBD TBD MBytes/sec Sector Sizes 512 user data blocks (default)
Variable (256 to 4096) in even sector siz es If sector size (n, bytes) is odd it will be rounded down to n-1.
Synchronous Transfer Rate
From 1.25 MByte/sec to 10.0 MBytes/sec (See section 11.5.)
Read/Write consecutive sectors on a track Yes Flaw reallocation performance impact (For flaws reallocated using the 1 sector time (typical) spare sectors per track or cylinder reallocation scheme.)
Flaw reallocation performance impact (For flaws reallocated using the spare 35 ms (typical) tracks per volume reallocation scheme.)
Track skew incorporated at format time 1.7 ms Cylinder skew incorporated at format time 3.0 ms Overhead time for one track cylinder switch <3 ms Typical Average rotational latency 5.54 ms
* [ ] All notes are listed in Section 5.3.1. ** Assumes system ability to support 5.0 Mb/s and no cable loss.
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5.3.1 Notes for sections 5.2 and 5.3.
[1] Execution time measured from receipt of the last Byte of the Command Descriptor Block (CDB) to the
request for a Status Byte Transfer to the Initiator (excluding latency and data transfer).
[2] Maximum times are specified over the worst case conditions of temperature, voltage margins and drive
orientation. When comparing specified seek times, care should be taken to distinguish between typical seek times and maximum seek times. The best comparison is obtained by system benchmark tests conducted under identical conditions. Maximum times do not include error recovery.
[3] Typical Seek values are measured under nominal conditions of temperature, voltage, and horizontal
orientation as measured on a representative sample of drives. [4] Assumes no errors and no sector has been relocated. [5] Rate measured from the start of the first sector transfer to or from the Host. [6] Assumes the Initiator immediately sends Write Data to the drive when requested. [7] Command execution requires a data transfer phase (data to or from the disc media). Assumes the
initiator is instantly ready to send/receive the data when the drive generates first request for a data byte
transfer, and assumes an average data transfer rate between the drive and the Initiator of 5 MBytes/
sec.
[8] All performance characteristics assume that automatic adaptive temperature compensation is not in
process when the SCSI command is received. A SCSI command being executed is not interrupted for
automatic adaptive temperature compensation. If adaptive thermal compensation is in process when a
SCSI command is received, the command is queued until the compensation for the specific head being
compensated completes. When compensation completes for the specific head being compensated, the
first queued SCSI command is executed. When execution of the first queued command is complete, the
drive continues the compensation for the remaining head(s). The abov e procedure continues until com-
pensation for all heads is completed, or until one minute has elapsed. If the compensation for all heads
is not complete in one minute, the drive performs compensation for all of the remaining heads sequen-
tially without any interruption. The drive initiates an automatic adaptive temper ature compensation cycle
approximately once every 10 minutes and only when it detects a bus free condition between com-
mands. Automatic adaptive temperature compensation takes less than 0.1% of bus time. Automatic
temperature compensation also occurs at other times, but should be transparent to the user (e.g.,
during format, Rezero Command, at spindle up, during read error recovery , and during Reassign Bloc k
functions). A Rezero command can be used to reset the thermal compensation timer back to its start so
that the host can know when the interruption for thermal compensation will occur.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
_____________________________________________________________________________________
5.4 Start/stop time
After DC power has been applied, the drive becomes ready within 20 seconds (17 seconds typical) if the Motor Start Option is disabled (i.e. the motor starts as soon as the power has been applied). During this time the drive will transfer commands over the SCSI interface but may take up to 3 seconds to respond back to the host. Stop time is less than 20 seconds from remo val of DC power.
If the Motor Start Option is enabled the internal controller accepts the commands listed in the SCSI Interface Product Manual* less than 3 seconds after DC power has been applied. After the Motor Start Command has been received the drive typically becomes ready for normal operations within 13.5 seconds. The Motor Start Command can also be used to command the drive to stop the spindle*.
There is no power control switch on the drive.
5.5 Prefetch/multi-segmented cache control
The drive provides prefetch (read look-ahead) and multi-segmented cache control algorithms that in many cases can enhance system performance. “Cache” as used herein refers to the drive buffer storage space when it is used in “cache” operations. To select prefetch and cache features the host sends the Mode Select command with the proper values in the applicable bytes in Mode Page 08h*. Prefetch and cache operation are independent features from the standpoint that each is enabled and disabled independently via the Mode Select command. Ho wev er , in actual operation the pref etch f eature ov erlaps cache operation somewhat as is noted in sections 5.5.1 and 5.5.2.
13
All default cache and prefetch Mode parameter values (Mode Page 08h) for standard OEM versions of this drive family are given in T ab les 11.3.2-1 through 11.3.2-4.
5.5.1 Cache operation
In general, 240 Kbytes of the 256 Kbytes of ph ysical buffer space in the driv e can be used as storage space for cache operations. The buff er can be divided into logical segments (Mode Select Page 08h, b yte 13) from which data is read and to which data is written. The drive maintains a table of logical block disk medium addresses of the data stored in each segment of the buffer. If cache operation is enabled (RCD bit = 0 in Mode Page 08h, byte 2, bit 0. See SCSI Interface Product Manual*), data requested by the host with a Read command is retrieved from the buff er (if it is there), before any disc access is initiated. If cache operation is not enabled, the buff er (still segmented with required number of segments) is still used, b ut only as circular buffer segments during disc medium read operations (disregarding Prefetch operation for the moment). That is, the drive does not check in the buff er segments for the requested read data, b ut goes directly to the medium to retrieve it. The retrieved data merely passes through some buffer segment on the way to the host. All data transfers to the host are in accordance with “buffer-full” ratio rules. See explanations associ­ated with Mod page 02h (disconnect/reconnect control) in the SCSI Interface Product Manual*.
__________ *SCSI Interface Product Manual, P/N 77738479.
14
______________________________________________________________________________________ The following is a simplified description of a read operation with cache operation enabled:
Case A - A Read command is received and the first logical block (LB) is already in cache:
1. Drive transfers to the initiator the first LB requested plus all subsequent contiguous LB’s that are
already in the cache. This data may be in multiple segments.
2. When the requested LB is reached that is not in any cache segment, the drive fetches it and any
remaining requested LB’s from the disc and puts them in a segment of the cache. The drive transfers the remaining requested LB’s from the cache to the host in accordance with the disconnect/reconnect specification mentioned above.
3. If the prefetch feature is enabled, refer to section 5.5.2 for operation from this point. Case B - A Read command requests data, the first LB of which is not in any segment of the cache:
1. The drive fetches the requested LB’s from the disc and transf ers them into a segment, and from there
to the host in accordance with the disconnect/reconnect specification referred to in case A.
2. If the prefetch feature is enabled, refer to section 5.5.2 for operation from this point. Each buffer segment is actually a self-contained circular storage (wr ap-around occurs), the length of which
is an integer number of disc medium sectors. The wrap-around capability of the individual segments greatly enhances the buffer’s overall performance as a cache storage, allowing a wide range of user selectable configurations, which includes their use in the prefetch operation (if enabled), even when cache operation is disabled (see section 5.5.2). For the Hawk 1 family the Mode Select command, but the selecting the segment Sense command page 08h, bytes 14 and 15. If a size specification is sent by the host in a Mode Select command (bytes 14 and 15) no new segment size is set up by the drive, and if the “STRICT” bit in Mode page 00h (byte 2, bit 1) is set to one, the drive responds as it does for any attempt to change unchangeable parameters (see SCSI I/O Product Manual*). The Hawk 1 family of drives supports operation of any integer number of segments from 1 to 16. Divide the 245,760 b ytes in the b uff er b y the number of segments to get the size (in bytes) of each segment.
number
size
specification. The size in Kbytes of each segment is reported by the Mode
number
can not be directly selected.
of segments may be selected using the
Size
is selected only as a by-product of
5.5.2 Prefetch operation
If the Prefetch feature is enabled, data in contiguous logical blocks on the disc immediately beyond that which was requested by a Read command can be retriev ed and stored in the b uffer for immediate transfer from the buffer to the host on subsequent Read commands that request those logical blocks (this is true even if “cache” operation is disabled). Though the prefetch operation uses the buffer as a “cache”, finding the requested data in the buffer is a prefetch “hit”, not a “cache” operation “hit”. Prefetch is enabled using Mode Select page 08h, byte 12, bit 5 (Disable Read Ahead - DRA bit). DRA bit = 0 enables prefetch. Since data that is prefetched replaces data already in some buffer segment(s), the host can limit the amount of prefetch data to optimize system performance. The dr ive never prefetches more logical blocks than the number specified in the prefetch logical blocks ceiling bytes (8 and 9) of Mode page 08h.
During a prefetch operation, the drive crosses a cylinder boundary to fetch more data ity (DISC) bit is set to one in bit 4 of byte 2 of Mode parameters page 08h.
__________ *SCSI Interface Product Manual P/N 77738479.
only
if the Discontinu-
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
_____________________________________________________________________________________ The operation of the prefetch feature (when enabled by DRA = 0) can be modified to an adaptable prefetch
mode, wherein prefetch is disabled as long as two sequential read operations are of data. If two sequential Read operations request contiguous logical blocks of data, the drive automatically enables the prefetch feature for the end of the second Read operation. As long as sequential Read opera­tions request contiguous LB’s of data, pref etch oper ation remains enab led.
If the host uses software interleave, there will not likely ever be two sequential Read operations for contigu­ous LB’s, so the adaptiv e pref etch f eature k eeps pref etch disab led, e v en if the DRA bit enables it. Adaptive prefetch is enabled when the IC (Initiator Control) bit (Mode page 08h, byte 2, bit 7) is set to 0 and when DRA. = 0 (prefetch enabled).
5.6 Caching write data
Write caching is a write operation by the drive that makes use of a drive buff er storage area where the data to be written to the medium is stored in one or more segments while the drive performs the write command.
Write caching is enabled along with read caching. F or write caching, the same buff er space and segmenta­tion is used as set up for read functions. The buffer segmentation scheme is set up or changed indepen­dently , having nothing to do with whether or not read and write caching is enabled or disab led. When a write command is issued, the cache is first checked to see if any logical blocks that are to be written are already stored in the cache from a previous read or write command. If there are, the respective cache segments are cleared. The new data is cached for subsequent Read commands.
not
for contiguous blocks
15
If the number of write data logical blocks exceeds the size of the segment being written into when the end of the segment is reached, the data is written into the beginning of the same cache segment, overwriting the data that was written there at the beginning of the operation. Howev er, the drive does not o verwrite data that has not yet been written to the medium.
Tables 11.3.2-1 through 11.3.2-4 show Mode default settings for the Ha wk 1 family of drives.
5.7 Synchronized spindle operation
The synchronized spindles operation allows several drives operating from the same host to operate their spindles at the same synchronized rotational rate. Drives operating in a system in synchronized mode increase the system capacity and transfer rate in a cost effective manner.
The interface consists of a twisted pair cable that connects the drives in the synchronized system in a daisychain configuration as shown in Figure 5.7-1. Master/slave operation is automatically set by the drives in the system at power up time, or each drive in the system can be configured by the host (using a Mode Select command*) to operate in either the master or slave mode. While loading heads after power up, a drive checks for occurrences of the reference index signal (REFIND+). If there are no reference index pulses occurring, the drive takes over as master and begins sending the reference index signal. Drives can be re-configured by the host any time after power up to be master or slave by use of the Mode Select command Rigid Disc Drive Geometry page.* The master provides the reference signal to which all other drives phase lock, including the master . There is only one master per system, and that can be a drive or the host computer. All drives may be configured as slaves allowing the host to pro vide the ref erence signal. All drives default to the synchronized mode when powered up.
__________ *SCSI Interface Product Manual P/N 77738479.
16
______________________________________________________________________________________ Each drive can be configured for the non-synchronized mode in which it ignores any reference signal that
might be present. The connection of the synchronized ref erence signal to the host is required only if the host is to provide the reference signal. If the host does not provide the reference signal, the host should not be connected and the master should be drive #1. See Figure 5.7-1.
Master Sync
Source
Host
(or other drive)
SCSI Bus
System
Interface
J1
J1
37 [2]
37 [2]
Sync Interface
Spindle Control
+5V
Drive 1
Spindle Control
+5V
Drive 2
REFIND +
J6
6
5
R
T
R
T
[1]
J6
6
5
[1]
Spindle
37 [2]
Drive n
Control
+5V
R
J1
Notes:
[1] Configuration Select Header: (see Figure 10.1-1 and 10.2.1-1). [2] This connection is only available on the "NC" models
Figure 5.7-1. Synchronized drive interconnect diagram
J6
6
5
T
[1]
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
17
_____________________________________________________________________________________ The servo/read-write LSI on the master drive provides the reference signal (REFIND+). It is a 90.18 Hz
crystal generated signal. The signal is normally false/negated (nominal 0 V) and makes a transition to the true/asserted (nominal +5 V) le vel to indicate the ref erence position during the revolution period. The trailing (falling) edge of the reference signal is used by the master and the slave drives to phase lock their spindles. A maximum of 10 seconds is allowed for a slave to synchronize with the reference signal. Figure 5.7-2 shows the characteristics of the reference signal.
T
1
REFIND +
0
0.5 usec min. 500 usec max.
T = 0.0111 second (+/- 1.0% max); +/- 10 usec cycle to cycle v ariance; +/- 50 usec phase error while synchronized.
Figure 5.7-2. Synchronized reference signal characteristics
SCSI Interface Factors
The Rotational Position Locking (RPL) field in byte 17 (bits 0 and 1) of the Rigid Disc Drive Geometry mode parameters page (page 04h) is used for enabling/disabling spindle synchronization mode*. If the target fails to achieve synchronization, it shall create a unit attention to all initiators . The sense key shall be set to UNIT ATTENTION and the additional sense code set to RPL STATUS CHANGE. However, in automatic arbitra­tion mode, UNIT ATTENTION and the RPL STATUS CHANGE is not set.
If subsequent to achieving synchronization the target detects a change of synchronization:
1) and, if the logical unit is not presently ex ecuting an I/O process for the initiator, the target shall create a
unit attention condition. The sense key shall be set to UNIT ATTENTION and the additional sense code
set to RPL STATUS CHANGE.
2) and, if the logical unit is presently executing an I/O process and no other error occurs, the target shall
return CHECK CONDITION status. The sense k ey shall be set to RECO VERED ERR OR if the target is
able to complete the I/O process or HARDWARE ERROR if the target is unable to complete the I/O
process. The additional sense code is set to RPL STATUS CHANGE.
__________ *SCSI Interface Product Manual P/N 77738479.
18
______________________________________________________________________________________ The drive may be operated with a rotational ske w when synchronized. The rotational skew is applied in the
retarded direction (lagging the synchronized spindle master control). A rotational offset of up to 255/256 of a revolution lagging ma y be selected. The amount of offset is set by using the Mode Select command, Rigid Disc Drive Geometry page (page 04), byte 18*. The value in b yte 18 (0 - FFh) is the numerator of a fractional multiplier that has 256 as the denominator. F or example, 40h selects 40h/100h or 1/4 of a re volution lagging skew, 80h selects 1/2 revolution lagging skew and etc. Since the drive supports all offset values from 0 to 255, values sent by the initiator are not rounded off. The dr ive translation of the digital offset values to physical rotational offsets results in offset values whose phase error lies within the + or - 50 usec phase error with respect to the supplied 90.18 Hz reference signal.
The drive does not have the capability to adjust the rotational offset value requested by the initiator to a physical offset in the drive that corresponds in any way to sector boundaries or changes in ZBR zones. Such correspondences or changes, if required, must be formulated by the initiator in order for it to calculate the value of offset it sends to the drive.
__________ *SCSI Interface Product Manual P/N 77738479.
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