Quantum SCORPION 24 DDS-3 User Manual
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Scorpion 24 DDS-3 Tape Drive
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STD124000N
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STD224000N
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STD624000N
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Product Manual
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Scorpion 24 DDS-3 Tape Drive
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STD124000N
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STD224000N
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STD624000N
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Product Manual
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© 1997 Seagate Technology, Inc. All rights reserved
Publication Number: 10004436-002, Rev. B, May, 1998
Seagate, Seagate Technology, the Seagate logo, Scorpion and the Scorpion logo
are trademarks or registered trademarks of Seagate Technology, Inc. Other product
names are trademarks or registered 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 from Seagate Technology, Inc.
FCC Notice
This equipment generates and uses radio frequency energy and, if not installed and
used properly—that is, in strict accordance with the manufacturer’s instructions—
may cause interference to radio communications or radio and television reception. It
has been tested and found to comply with the limits for a Class B computing device
in accordance with the specifications in Part 15 of FCC Rules, which are designed to
provide reasonable protection against such interference in a residential installation.
However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause interference to radio or television
reception, which can be determined by turning the equipment on and off, you are
encouraged to try to correct the interference by one or more of the following
measures:
z
Reorient the receiving antenna.
z
Relocate the computer with respect to the receiver.
z
Move the computer into a different outlet so that the computer and receiver are
on different branch circuits.
If necessary, you should consult the dealer or an experienced radio/television
technician for additional suggestions. You may find the following booklet prepared
by the Federal Communications Commission helpful:
How to Identify and Resolve Radio-TV Interference Problems
This booklet (Stock No. 004-000-00345-4) is available from the U.S. Government
Printing Office, Washington, DC 20402.
Warning. Changes or modifications made to this equipment which have not been
expressly approved by Seagate Technology may cause radio and
television interference problems that could void the user’s authority to
operate the equipment.
Further, this equipment complies with the limits for a Class B digital apparatus in
accordance with Canadian Radio Interference Regulations.
Cet appareil numérique de la classe B est conforme au Règlement sur brouillage
radioélectrique, C. R. C., ch. 1374.
The external device drive described in this manual requires shielded interface cables
to comply with FCC emission limits.
Additional Warnings:
z
To prevent fire or electrical shock hazard, do not expose the unit to rain or
moisture.
z
To avoid electrical shock, do not open the cabinet.
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Refer servicing to qualified personnel.
Product Manual Page iii
About This Manual
All information contained in or disclosed by this document is considered proprietary
by Seagate Technology. By accepting this material, the recipient agrees that this
material and the information contained therein are held in confidence and in trust
and will not be used, reproduced in whole or in part, nor its contents revealed to
others, except to meet the purpose for which it was delivered. It is understood that
no right is conveyed to reproduce or translate any item herein disclosed without
express written permission from Seagate Technology.
Seagate Technology provides this manual “as is,” without warranty of any kind,
either expressed or implied, including, but not limited to, the implied warranties of
merchantability and fitness for a particular purpose. Seagate Technology reserves
the right to change, without notification, the specifications contained in this manual.
Seagate Technology assumes no responsibility for the accuracy, completeness,
sufficiency, or usefulness of this manual, nor for any problem that may arise from
the use of the information in this manual.
Following are brief descriptions of the sections in this manual.
Chapter 1, “Introduction” on page 1 provides general specifications, features and
an overview on DAT technology.
Chapter 2, “Specifications” on page 9 contains physical, performance,
environmental, power, drive tape handling and DAT cartridge specification tables.
Chapter 3, “Installation” on page 15 provides cautions, unpacking tips, inspection
information and installation/connection steps, including cabling requirements and
connector pinouts.
Chapter 4, “Drive Operations” on page 33 explains the simple operation of drives.
Chapter 5, “SCSI Interface” on page 43 lists general information about the SCSI-2
interface.
Chapter 6, “DDS-3 Tape Format” on page 47 explains the DDS, DDS-DC, DDS-2
and DDS-3 tape formats.
Chapter 7, “Data Compression” on page 61 describes the data compression
algorithm and explains pertinent information for effective use of data compression.
Chapter 8, “Theory of Operations” on page 71 details the functional operation of
various assemblies of the drives.
Chapter 9, “Maintenance and Reliability” on page 83 presents maintenance
procedures and reliability information.
Appendix A, “Acronyms and Measurements” on page 87 lists the acronyms and
measurements used in the manual.
Appendix B, “Vendor-Unique SCSI Information” on page 91 provides specific
SCSI information for programming and retrieving configuration data.
The glossary on page 95 defines key terms.
Page iv DAT Drives
Contents
1 Introduction.......................................................................1
Overview..............................................................................................1
DDS Format Standard Compatibility 1
Scorpion 24 Capacity and Transfer Rates 2
Features ..............................................................................................3
Models.................................................................................................4
DAT Technology Overview...................................................................6
Helical Scan Recording..................................................................6
Recording Formats ........................................................................7
DDS-3 Recording Format ........................................................7
DDS-2 Recording Format ........................................................7
DDS Recording Format ...........................................................7
DDS-DC Recording Format.....................................................8
2 Specifications.................................................................... 9
Overview..............................................................................................9
Physical Specifications.........................................................................9
Power Specifications..........................................................................11
Drive Performance Specifications....................................................... 12
Environmental Requirements .............................................................13
DDS Cartridge Specifications.............................................................13
Regulatory Compliance......................................................................14
3 Installation.......................................................................15
Introduction........................................................................................15
Guidelines and Cautions (Internal Models) .........................................15
Unpacking and Inspection..................................................................16
Cabling and Connectors.....................................................................16
Cabling Considerations................................................................16
Electrical Characteristics..............................................................16
SCSI Connector—Internal Models ...............................................18
SCSI Connector—External Models ..............................................19
Installing Internal Drives.....................................................................20
Configuring Options.....................................................................20
Setting the Switchbank Parameters .............................................20
SCSI Device Address (S1, S2, S3) .......................................22
Media Recognition System (MRS) (S4) .................................22
Product Manual Page v
Contents
Parity Check Enable/Disable (S5)..........................................23
DDS Pass-Through Mode Enable/Disable (S6)......................23
Inquiry String (S7)..................................................................23
Power-on Self-Test Mode Enable/Disable (S8) ......................23
Switches 9 and 10.................................................................23
Setting the Jumpers...............................................................24
SCSI Device Address Jumpers.............................................. 25
Hardware Data Compression.................................................26
Active Terminator.................................................................. 26
Terminator Power..................................................................26
Mounting the Drive.......................................................................27
Completing the Power and Interface Connections........................29
Installing External Drives....................................................................29
Selecting the SCSI Address.........................................................30
Completing the Interface Connection ...........................................30
Connecting the Power Cord......................................................... 31
4 Drive Operations .............................................................33
Introduction........................................................................................33
Data Compression Operation.............................................................33
Front Panel LED Operation................................................................34
Loading/Unloading the Cartridge........................................................ 37
Loading/Unloading a Cartridge (Normal Operation)......................37
Unloading a Cartridge (Manual Operation)................................... 38
Using a Blank Cartridge .....................................................................39
Using a Cartridge Containing Data ..................................................... 40
Loading Revised Firmware Using Seagate Firmware Cartridges......... 40
Flash Memory....................................................................................40
Firmware Download Process.............................................................. 41
5 SCSI Interface..................................................................43
Introduction........................................................................................43
SCSI-2 Interface................................................................................ 43
ANSI X3.131, 199x Conformance Statement (SCSI-2).......................45
General Features...............................................................................45
Typical System Configurations...........................................................46
6 DDS-3 Tape Format.........................................................47
Introduction to DDS Recording Format Standards..............................47
DDS-3 Tape Format...........................................................................47
Basic Groups...............................................................................48
Entities ........................................................................................49
Subgroups...................................................................................49
Basic Group Transformation Summary ........................................49
Subcode Information....................................................................49
Page vi DAT Drives
Contents
Subcode Location........................................................................49
DDS-3 Track Geometry ...............................................................50
Recorded Patterns.......................................................................51
Format of a Track........................................................................51
Positioning Accuracy....................................................................52
Timing Tracking...........................................................................52
Tape Layouts in the DDS-3 Standard.................................................53
Layout of a Single Data Space Tape (Single Partition)........................53
Device Area................................................................................. 54
Reference Area............................................................................54
System Area................................................................................55
Data Area....................................................................................55
Appending to Tape.......................................................................55
EOD Area....................................................................................57
Early Warning Point (EWP).......................................................... 57
Initialization..................................................................................57
Layout of a Partitioned Tape ..............................................................58
Partition 1....................................................................................59
Partition 0....................................................................................59
Initialization of Partitioned Tapes..................................................59
Housekeeping Frames.......................................................................60
DDS-3 Recording Format Standard—Further Reference....................60
7 Data Compression .......................................................... 61
Introduction........................................................................................ 61
Data Compression—General..............................................................61
Data Compression Considerations...............................................62
Hardware Compression ...............................................................63
Data Integrity...............................................................................63
DCLZ Algorithm .................................................................................64
DCLZ Algorithm...........................................................................64
Simplified Compression Operation............................................... 64
Dictionary ....................................................................................65
Simplified Decompression Operation............................................66
SCSI/Data-Compression Chip............................................................68
Overview .....................................................................................68
Features......................................................................................68
8 Theory of Operations...................................................... 71
Overview............................................................................................71
The STD124000N Drive...............................................................72
Motors and Control Circuits..........................................................73
SCSI Controller............................................................................ 74
Helical Scan Recording—Four-Head Design................................75
Motors and Control Circuits................................................................ 76
Read and Write LSI .....................................................................77
Timing Tracking Circuitry .............................................................77
SCSI Controller............................................................................ 77
Product Manual Page vii
Contents
Flash Memory.................................................................................... 77
Sensors .............................................................................................78
Read-After-Write................................................................................78
Media Recognition System (MRS)...................................................... 79
DDS Data Cartridge...........................................................................79
9 Maintenance and Reliability...........................................83
Maintenance...................................................................................... 83
Head Cleaning.............................................................................83
Automatic Drive Spin-Down and Write ......................................... 84
Guidelines for High Temperature or Humidity Conditions
(Outside the Specified Operating Environment)................... 84
Reliability ...........................................................................................85
Mean Time Between Failures.......................................................85
Mean Time To Repair.................................................................. 85
A Acronyms and Measurements .......................................87
Acronyms and Abbreviations..............................................................87
Measurements...................................................................................89
B Vendor-Unique SCSI Information ..................................91
Overview............................................................................................91
MODE SELECT Flash Memory Configuration Page (30
MODE SENSE Flash Memory Configuration Page (30
)...................92
H
).....................93
H
Glossary......................................................................................95
Page viii DAT Drives
Figures
Figure 1. 3.5-inch Internal DDS Drive...................................................5
Figure 2. 5.25-Inch Internal DDS Drive.................................................5
Figure 3. External DDS Drive...............................................................6
Figure 4. Internal DDS Drive—General Dimensions ...........................10
Figure 5. Internal DDS Drive with Rails—General Dimensions............10
Figure 6. External Subsystem—General Dimensions .........................11
Figure 7. Switchbank Access—3.5-Inch Internal Model ......................20
Figure 8. Switchbank Access—5.25-Inch Internal Model ....................21
Figure 9. Dip Switch Default Settings .................................................22
Figure 10. Location of Jumpers for Internal Model..............................24
Figure 11. Location of Jumpers for Internal Model with Rails..............24
Figure 12. Jumper Configurations.......................................................25
Figure 13. Mounting Hole Locations (Internal Drive without Rails).......27
Figure 14. Mounting Hole Locations (Internal Drive with Rails) ...........28
Figure 15. Rear Panel (External Model)..............................................30
Figure 16. Daisy Chain Diagram.........................................................31
Figure 17. Front Panel—Internal Model..............................................35
Figure 18. Front Panel—Internal Model with Rails..............................36
Figure 19. Front Panel—External Subsytem.......................................36
Figure 20. Cartridge Loading (Internal DAT Drive)..............................37
Figure 21. Locations on Drive.............................................................38
Figure 22. SCSI System Sample Configurations.................................46
Figure 23. Structure of a Basic Group................................................48
Figure 24. Track Configuration...........................................................50
Figure 25. Timing Tracking.................................................................53
Figure 26. Layout of a Single Data Space Tape..................................54
Figure 27. Appending Rules...............................................................55
Figure 28. Tolerance on Seamless Appending ...................................56
Figure 29. Layout of a Partitioned Tape..............................................58
Figure 30. Layout of SCSI/Data Compression Device.........................69
Figure 31. Simplified Block Diagram—Scorpion 24 DDS-3 Drive ........73
Figure 32. Block Diagram—SCSI Controller DAT Models...................74
Figure 33. Four-Head Design.............................................................75
Figure 34. Alternate Azimuth Angles ..................................................76
Figure 35. DDS Cartridge...................................................................80
Figure 36. Cartridge Design Features.................................................81
Figure 37. Write-Protect Tab on the DDS Cartridge............................81
Product Manual Page ix
Figures
Page DAT Drives
x
Introduction
Overview
1
®
The Seagate
computer environments that require high-performance, high-capacity data storage.
Based on a 3.5-inch mechanism, the internal and external Scorpion 24 models
provide 12 Gbytes of data-storage capacity, 24 Gbytes compressed, with a native
transfer rate of 1.1 Mbytes per second, 2.2 Mbytes per second compressed.
The Scorpion 24 drive combines established DAT technology, high-density
recording and hardware data-compression capability along with Seagate’s proven
computer grade design to provide unmatched reliability and performance
characteristics among DDS products. The Scorpion 24 is ideal for workstation,
server and network/enterprise applications such as:
z
Backup of high-capacity fixed discs
z
Data interchange between systems
z
Network server
z
Loader products
z
Online data collection
z
Near-line secondary storage for text, graphics or multimedia information of all
types
Scorpion
®
24 digital data storage (DDS) drive is designed for
z
Archival storage
DDS Format Standard Compatibility
The Scorpion 24 drive supports the DDS-3, DDS-2 and DDS recording formats.
Compatibility with each of these standards ensures complete write and read
interchange of recorded digital data between all compliant drive and media vendors.
Additionally, the Scorpion 24 drive supports DDS-DC, the DDS data compression
standard, effectively doubling storage capacity and transfer rates.
Product Manual Page 1
Chapter 1 Introduction
The Scorpion 24 drive complies with:
z
The DDS recording format standard,
ANSI/ECMA-139, 3,81mm Wide Magnetic
Tape Cartridge for Information Interchange - Helical Scan Recording - DDS
Format.
z
The DDS-DC recording format standard,
ANSI/ECMA-150, 3,81mm Wide
Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording DDS-DC Format using 60 m and 90 m Length Tapes.
z
The DDS-2 recording format standard,
ANSI/ECMA-198, 3,81mm Wide
Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording DDS-2 Format using 120 m Length Tapes.
z
The DDS-3 recording format standard,
ANSI/ECMA-236, 3,81mm Wide
Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording DDS-3 Format using 125 m Length Tapes.
Scorpion 24 Capacity and Transfer Rates
The Scorpion 24 provides the following capacities and transfer rates, depending on
recording mode and tape length:
Recording Mode
DDS DDS-DC DDS-2 DDS-3
Tape length 60 meter 90 meter 120 meter 125 meter
Capacity (native) 1.3 Gbytes 2.0 Gbytes 4.0 Gbytes 12.0 Gbytes
Capacity (compressed) N/A 4.0 Gbytes 8.0 Gbytes 24.0 Gbytes
Transfer rate (native) 780
Kbytes/sec
780
Kbytes/sec
780
Kbytes/sec
1.1
Mbytes/sec
In data-compression mode, the Seagate Scorpion 24 drive typically doubles the
storage capacity and transfer rate of the native uncompressed operation. Tape
capacity and sustained data-transfer rate are also dependent upon the
characteristics of the files being compressed, along with other system parameters,
including the speed of the host, the operating system and the application software
used.
The Scorpion 24 drive also offers synchronous or asynchronous SCSI transfers with
a high-speed burst data-transfer rate of 10 Mbytes per second.
The Scorpion 24 provides unmatched reliability through three levels of errorcorrection code (ECC) and the four-head design, which provides for read-after-write
(RAW) error detection and correction. The Scorpion 24 also contains an onboard
serial port that provides the capability for extensive testing of the drives.
Page 2 DAT Drives
Introduction Chapter 1
Features
The Scorpion 24 DDS drive represents Seagate’s commitment to engineering
reliable and durable tape drive products that implement leading-edge technology.
Key features of the drive include:
z
Platform based on 3.5-inch DDS drive components
z
3.5-inch internal form-factor for installation in a 3.5-inch half-height space
(model STD124000N)
z
3.5-inch drive with factory-installed 5.25-inch mounting rails and bezel for
installation in a 5.25-inch half-height space (model STD224000N)
z
External subsystem with built-in, auto-sensing, worldwide power supply (model
STD624000N)
z
Capability to write and read DDS-3, DDS-2, DDS-DC and DDS cartridges
z
Advanced onboard DDS-DC hardware using Data Compression Lempel-Ziv
(DCLZ) data-compression algorithm
z
ANSI/ECMA DDS-3, DDS-2, DDS-DC and DDS tape format compliance for
compatibility and interchange
z
High-speed random access of 20 seconds (average) to any file on a 60 m tape;
30 seconds for a 90 m tape; 40 seconds on a 120 m tape; and 40 seconds on a
125 m tape
z
High-speed transfer rates for fast backups:
– 1.1 Mbytes per second (66 Mbytes per min) typical—uncompressed data
– 2.2 Kbytes per second (132 Mbytes per min) typical—compressed data
z
High-performance SCSI burst transfer rate of 7 Mbytes per second
asynchronous and 10 Mbytes per second synchronous
z
Flash memory to store setup parameters
z
Four-head design with RAW error detection and rewrites
z
Three levels of ECC to ensure data integrity
z
Uncorrectable error rate of less than 1 in 1015 bits
z
Flash memory to enable field firmware upgrades
z
Custom Seagate-designed LSI circuitry to reduce component count and boost
drive reliability
z
Advanced, single-chip, DDS formatter LSI
z
Low power consumption—less than 5.5 watts (typical) for internal drives
Product Manual Page 3
Chapter 1 Introduction
z
Single-ended SCSI connection with these features:
– Embedded full LSI, high-speed SCSI-2 controller
– Software selectable synchronous or asynchronous SCSI data transfer
– Onboard output jack on internal models for configuring the SCSI
address if repackaged in an external box
z
Automatic power-on self-tests available
z
Manual emergency cartridge ejection procedure
z
Support for TapeAlert™ Certified Solutions
Models
The Scorpion 24 3.5-inch and 5.25-inch internal drive form-factors are tailored for
easy installation in today’s computers, and the full-featured embedded SCSI
controller facilitates easy integration into a variety of systems.
Scorpion 24 Model Names
Capacity 24.0 Gbytes*
3.5-in internal STD124000N
5.25-in internal STD224000N
External STD624000N
*Typical with data compression
Scorpion 24 models include:
z
A 3.5-inch, half-height DDS-3 drive that mounts internally (model
STD124000N).
z
A 5.25-inch, half-height DDS-3 drive that consists of a 3.5-inch drive with 5.25inch mounting rails and bezel that mounts internally in a 5.25-inch, half-height
space (model STD224000N).
z
A complete external subsystem that contains the 3.5-inch DDS-3 drive and
built-in worldwide power supply (model STD624000N).
Page 4 DAT Drives
Introduction Chapter 1
Figures 1, 2 and 3 illustrate the internal, internal with rails and external drives,
respectively.
Figure 1. 3.5-Inch Internal DDS Drive
Figure 2. 5.25-Inch Internal DDS Drive
Product Manual Page 5
Chapter 1 Introduction
Figure 3. External DDS Drive
DAT Technology Overview
Developed for the audio electronics market, DAT technology was first applied in
computer peripherals in the late 1980s. Unlike traditional magnetic tape audio
cartridge products, DAT technology proves inherently reliable through the
scan recording method,
error rate. All DAT products, including computer implementations, use the helical
scan recording method. This recording method has been used in professional video
tape recorders (VTRs) since 1956 and in home video cartridge recorders (VCRs)
since 1974. In 1986, DAT products that used helical scan technology were first
developed for audio applications. DAT consumer products are specifically designed
for digital audio recording and playback.
Helical Scan Recording
Helical scan recording was originally developed as a method of efficiently recording
high-quality television signals on a relatively slow moving tape. It requires that both
the tape and the recording head move simultaneously. This recording method
results in an extremely high recording density, far higher than can be achieved with
stationary-head devices such as 1/2-inch open-reel or 1/4-inch cartridge tapes. (See
chapter 8, “Helical Scan Recording—Four-Head Design” for additional information.)
In helical scan recording, both the read and write heads are located on a rapidly
rotating cylinder or drum. The cylinder is tilted at an angle in relation to the vertical
axis of the tape. As the tape moves horizontally, it wraps around the part of the
circumference of the cylinder (102°) so that the head enters at one edge of the tape
and exits at the other edge before the tape unwraps.
helical
which provides a high recording density with a very low
Page 6 DAT Drives
Introduction Chapter 1
The horizontal movement of the tape in combination with the angular movement of
the cylinder causes the track to be recorded diagonally across the tape rather than
straight down its length. The resulting recorded track, nearly one inch, is
approximately eight times longer than the width of the tape.
Recording Formats
The Seagate Scorpion 24 DDS drive is designed to comply with the industrystandard DDS-3, DDS-2, DDS-DC and DDS recording formats. These formats are
summarized in the following text.
DDS-3 Recording Format
The DDS-3 recording format provides for writing data in helical tracks that are the
same width as DDS-2. The significant capacity increase associated with DDS-3 is
achieved by: 1) doubling linear recording density from 61 Kbpi (DDS-2) to 122 Kbpi
along with the use of PRM L enc oding; 2) increasing tape length to 125 meters and
3) using the timing tracking system, which eliminates the need for dedicated top and
bottom servo burst information associated with the previous ATF system.
DDS-2 Recording Format
DDS Recording Format
The DDS-2 or narrow track recording format provides for writing data in helical
tracks that are narrower than the previous DDS track width. This format doubles
capacity by increasing track density one and a half times, along with a 33% increase
in tape length; the higher output MP+ media associated with the 120-m DDS-2
cartridges ensures reliable data integrity given the decrease in track widths from
13.6 µm with DDS and DDS-DC to 9 µm with DDS-2.
This standard format was codeveloped by DDS manufacturers to support DAT
devices as computer peripherals. The objectives of DDS are to maximize storage
capacity and performance, facilitate data interchange, provide compatibility with
existing tape storage command sets and provide extremely fast random access.
The DDS format also takes advantage of the helical scan recording method and the
inherent error correction capability of the DAT technology to augment error detection
and correction.
The format consists of a finite sequence of data groups where each data group is a
fixed-length recording area. A data group is made up of 22 data frames and 1 ECC
frame; each frame is made up of two helical scan tracks. The advantages of the
fixed-length data group is that ECC is easily generated, and buffering requirements
are simplified. (See Chapter 6, “Tape Formats,” for additional information.)
Although data groups are fixed-length and always contain 22 data frames, the DDS
format is designed such that variable-length computer records can be stored in the
fixed-length data groups.
Product Manual Page 7
Chapter 1 Introduction
DDS-DC Recording Format
A superset of the basic DDS format, DDS-DC drives can write compressed and
uncompressed data to the same cartridge. Because DDS-DC is based on the DDS
format, backward-compatibility is maintained.
Introduced by the DDS Manufacturers Group and approved by ANSI and ECMA,
DDS-DC is a
lossless
compression algorithms based on substitution—such as those of the
record compression
industry-standard format that provides support for
Lempel-Ziv family.
This format supports compressed and uncompressed records. A recorded DDS
cartridge may contain compressed records, uncompressed records, filemarks and
setmarks. Compressed records exist within recorded objects called
entities
. Entities
and uncompressed records are collected into groups.
Many aspects of the DDS-DC format are identical to those of the DDS format:
z
The series of transformations (randomizing, interleaving, generation and
inclusion of two Reed-Solomon error-correction codes) applied to a group
before recording
z
The tape layout
z
The third group-based level of Reed-Solomon error-correction codes (C3)
The only differences between the DDS and DDS-DC formats are in the contents of
the groups.
Page 8 DAT Drives
Specifications
Overview
This chapter includes technical specifications for the internal and external SCSI
drives. This information covers the following specifications and requirements:
z
z
z
z
z
z
2
Physical specifications
Power requirements
Drive performance specifications
Environmental requirements
DAT cartridge specifications
Regulatory compliance
Physical Specifications
The physical specifications of the Scorpion 24 internal and external models are
listed in the following table:
Specification Internal Internal with rails External
Height 1.6 in/41.2 mm 1.6 in/41.2 mm 2.7 in/69 mm
Width 4.0 in/101.6 mm 5.7 in/146.0 mm 6.1 in/155.0 mm
Length 5.7 in/146.0 mm 6.9 in/175.0 mm 9.3 in/236.0 mm
Weight 2.0 lb/0.85 kg 2.4 lb/1.1 kg 4.1 lb/1.8 kg
Figures 4, 5 and 6 illustrate the general dimensions of the internal and external drive
models. Drive dimensions are in millimeters.
Product Manual Page 9
Chapter 2 Specifications
101.6
6
41.3
146
Cassette
104.1
in Place (Green)
41.2
Drive Busy (Yellow)
Figure 4. Internal DDS Drive—General Dimensions
146
41.4
174.6
6
Cassette
in Place (Green)
Drive Busy (Yellow)
149.1
41.2
Figure 5. Internal DDS Drive with Rails—General Dimensions
Page 10 DAT Drives
Specifications Chapter 2
236
Drive Busy
(Yellow)
Cassette in Place
(Green)
Power On
(Green)
155
69
Figure 6. External Subsystem—General Dimensions
Power Specifications
The following table lists the power specifications for the internal Scorpion 24 drives.
DC Voltage +12 VDC +5 VDC
Voltage Tolerance + or – 10% + or – 7%
Operational Current 250 milliamps 600 milliamps
Standby Current 50 milliamps 550 milliamps
Peak 600 milliamps 800 milliamps
Ripple (peak-to-peak)
Power dissipation
(Standby)
Power dissipation
(Operating)
The following table lists pin assignments of the power connector for the internal
models.
Pin Assignment
1 +12 VDC
2 +12 return
3 +5 return
4 +5 VDC
≤
100 mV
≤
100 mV
< 3.3 watts < 2.2 watts
< 5.5 watts < 5.5 watts
Product Manual Page 11
Chapter 2 Specifications
The external drives have a built-in power supply that senses the incoming voltage
and automatically adapts to voltages within the range of 100 to 240 volts, 50 to 60
Hz. The following table lists its power specifications.
Specification AC Input Voltage
100 (Japan) 120 (US) 240 (European)
AC Input Current 100 milliamps 85 milliamps 170 milliamps
AC Input Power 10.0 watts 10.0 watts 10.0 watts
Drive Performance Specifications
The following table lists the specifications for the Scorpion 24 drive.
Capacity
60 m MP
90 m MP
120 m MP+
125 m MP++
2.6 Gbytes
4.0 Gbytes
8.0 Gbytes
24.0 Gbytes
Recording density 122,000 bpi
Flux density 152,400 ftpi
Track density 2,804 tpi
Error recovery Read-after-write
Reed Solomon ECC (C3 - 3 levels)
Recording unrecoverable errors < 1 in 10
Tape drive type Computer grade 4DD mechanism
Head configuration 2 read heads, 2 write heads
Recording format DDS-3
Recording method Helical scan (R-DAT)
Cartridge 2.9 in × 2.1 in × 0.4 in
Transfer rate (sustained) 2,200 Kbytes per sec DC ON
Synchronous transfer rate (burst) 10 Mbytes per sec max
Asynchronous transfer rate (burst) 7 Mbytes per sec max
Search speed 200 X normal speed
Average access time
60 m cartridge
90 m cartridge
120 m cartridge
125 m cartridge
Drum rotation speed 4,000 RPM (DDS-3 mode)
Tape speed 0.43 in per sec
Head-to-tape speed 246.94 in per sec
<20 sec
<30 sec
<40 sec
<40 sec
8,000 RPM (DDS-2, DDS modes)
15
data bits
Page 12 DAT Drives
Specifications Chapter 2
Environmental Requirements
The following table lists the environmental specifications for DDS drives. You can
mount internal DDS drives either vertically (drive left side up or right side up) or
horizontally.
Specification Operational Nonoperational
Temperature +41o to +113oF
(+ 5o to + 45oC)
Thermal gradient 2oC per minute
(no condensation)
Relative humidity 20% to 80%
noncondensing
Maximum wet bulb temperature 78.8oF (26oC) No condensation
Altitude –100 to +4,575 meters –300 to +15,200
Vibration — 1.5 g (5 to 500 Hz)
Sweep Test 1.20 mm peak-to-peak
(5–17 HZ)
0.73 G peak (17 to 150 Hz)
0.50 G peak (150–500 Hz)
Sweep Rate 8 decades per hour —
Dwell Test (15 min) 0.90 mm peak-to-peak
(5–17 Hz)
0.55 G peak (17–150 Hz)
0.25 G peak (150–500 Hz)
Acoustic level idling (A-wt sum) 45 dBA maximum —
Acoustic level operational
(A-wt sum)
Shock (1/2 sine wave) 10 Gs peak, 11 msec 50 Gs peak, 11 msec
50 dBA maximum
(measured in suitable
enclosure at 3-ft distance
and operator height)
1
1
o
–40
to +149oF
(–40o to + 65oC)
Below condensation
0% to 90%
noncondensing
meters (power off)
—
—
—
—
—
—
—
2
2
1. Mechanism and media 2. Mechanism
DDS Cartridge Specifications
DDS drives provide maximum data integrity and reliability when Seagate-qualified
DDS cartridges are used as the recording media. Seagate maintains an ongoing
program to qualify manufacturers of DDS cartridges.
The following cartridges are recommended:
z
DDS data cartridge: model M31300, 60-meter tape
z
DDS data cartridge: model M32000, 90-meter tape
z
DDS-2 data cartridge: model M34000, 120-meter tape
z
DDS-3 data cartridge: model M312000, 125-meter tape
z
DDS cleaning cartridge: model M91301
Contact your Seagate sales representative for information on qualified DDS data
and cleaning cartridge manufacturers and models.
Product Manual Page 13
Chapter 2 Specifications
Regulatory Compliance
These DDS drives comply with the regulations listed in the following table.
Agency Regulation
CSA C22.2, No. 950-M89
TUV-RHEINLAND EN 60 950
UL 1950
FCC Class A and Class B
CE CE compliance
1. Required compliance for external model; verification on file for internal models.
Use these drives only in equipment where the combination has been determined to
be suitable by an appropriate certification organization (for example, Underwriters
Laboratories Inc. or the Canadian Standards Association in North America). You
should also consider the following safety points:
Install the drive in an enclosure that limits the user’s access to live parts, gives
adequate system stability and provides the necessary grounding for the drive.
1
Provide the correct voltages (+5 VDC and +12 VDC) based on the regulation
applied—Extra Low Voltage (SEC) for UL and CSA and Safety Extra Low
Voltage for BSI and VDE (if applicable).
Page 14 DAT Drives
Installation
Introduction
3
This chapter explains how to install the Scorpion 24 drive. Some of the information
relates to all models; other information is specifically aimed at either the internal or
external models. The following paragraphs briefly outline the organization of this
chapter.
Guidelines and Cautions: lists guidelines for handling the internal drive.
z
Unpacking and Inspection: contains general information that you should read
z
before installation.
Cabling and Connectors: gives specific cabling requirements and connector
z
pinouts for the drive.
Installing the Internal Drives: describes installing the 3.5-inch internal drive
z
and the 3.5-inch drive with 5.25-inch mounting rails and bezel.
Installing the External Drive: describes installing the external subsystem.
z
Guidelines and Cautions (Internal Models)
The following guidelines and cautions apply to handling and installing the Scorpion
24 internal drive. Keep them in mind as you install the drive.
z
Internal drives contain some exposed components that are sensitive to static
electricity. To reduce the possibility of damage from static discharge, the drives
are shipped in a protective antistatic bag.
z
Do not remove the drive from the antistatic bag until you are ready to install it.
z
Before you remove the drive from the antistatic bag, touch a metal or grounded
surface to discharge any static electricity buildup from your body.
z
Hold the drive by its edges only, and avoid direct contact with any exposed
parts of the printed circuit board (PCB).
z
While not installed, always lay the drive either on top of the antistatic bag or
place it inside of the bag to reduce the chance of damage from static discharge.
Product Manual Page 15
Chapter 3 Installation
Unpacking and Inspection
Although drives are inspected and carefully packaged at the factory, damage may
occur during shipping. Follow these steps for unpacking the drive.
1. Visually inspect the shipping containers and notify your carrier immediately of
any damage.
2. Place shipping containers on a flat, clean, stable surface; then carefully remove
and verify the contents against the packing list.
If parts are missing or the equipment is damaged, notify your Seagate
representative.
3. Always save the containers and packing materials for any future reshipment.
Cabling and Connectors
The Scorpion 24 drive provides a standard single-ended SCSI interface. ANSI SCSI
standards specify the technical requirements for correctly cabling and connecting
single-ended devices. This section provides some basic information about SCSI
cabling and connectors for the drives.
Cabling Considerations
You can use either a 50-pin flat cable or a 25-signal twisted-pair cable with a
maximum length of 6 meters (19 feet) to connect the drives to the SCSI host
adapter output. If twisted-pair cabling is used, connect the twisted pairs to physically
opposing contacts on the connector.
A stub length no greater than 0.1 meter should be used off the mainline connection
within any connected equipment.
The cable characteristic impedance should be between 90 ohms and 140 ohms. A
cable characteristic impedance of greater than 100 ohms is recommended.
To minimize noise and ensure even distribution of terminator power, the minimum
recommended conductor size is 28 AWG (0.08042 mm
Electrical Characteristics
This section lists measurements of various electrical signals in relation to the singleended SCSI connection. For these measurements, SCSI bus termination is
assumed to be external to the SCSI device.
2
).
Page 16 DAT Drives
Installation Chapter 3
All signals except GROUND and TEMPWR must be terminated at both ends of the
cable. Each signal termination consists of 220 ohms (± 5%) to TEMPWR and 330
ohms (± 5%) to GROUND and must meet the following specifications or
requirements:
z
Terminators must supply a characteristic impedance of 100 to 132 ohms.
z
External terminators must be powered by the TEMPWR line, and units that
provide terminator power to the cable must have:
V
= 4.25 to 5.25 VDC
TERM
900 milliamps minimum source drive capability
The external drive normally supplies terminator power to the SCSI bus.
z
When TEMPWR matches the above values, the voltage of released signal lines
must be at least 2.5 VDC.
z
When a driver asserts a line and pulls it to 0.5 VDC, the current available to the
signal line driver may not exceed 48 milliamps. The first two terminators may
only supply 44.8 milliamps of this current.
z
When at least one device supplies TEMPWR, these conditions may be met by
any valid configuration of targets and initiators.
All signals use open-collector drivers. The output characteristics (measured at the
connector of the drive) of signals driven by the drive are:
z
Signal assertion (low-level output voltage): 0.0 to 0.5 VDC at 48 milliamps
sinking
z
Signal negation (high-level output voltage): 2.5 to 5.25 VDC
Signals received by the drive have the following characteristics.
z
Signal assertion (low-level input voltage): 0.0 to 0.8 VDC
z
Signal negation (high-level input voltage): 2.0 to 5.25 VDC
z
Maximum input load (low-level input current): –0.4 at 0.5 VDC
z
Minimum input hysteresis: 0.2 VDC
Product Manual Page 17
Chapter 3 Installation
SCSI Connector—Internal Models
The internal drive provides a 50-pin, right-angle, dual-row connector on the main
PCB at the rear of the drive. The pin assignments for this single-ended connector
are listed in the following table.
Note. All odd pins, except pin 25, are connected to signal ground at the drive. Pin
25 is left open. A signal name or abbreviation preceded by a dash indicates
that the signal is active-low.
Pin Assignment
2 –DB(0)
4 –DB(1)
6 –DB(2)
8 –DB(3)
10 –DB(4)
12 –DB(5)
14 –DB(6)
16 –DB(7)
18 –DB(P)
20 GROUND
22 GROUND
24 GROUND
26 TERMINATOR POWER
28 GROUND
30 GROUND
32 –ATN
34 GROUND
36 –BSY
38 –ACK
2
–
40
RST
42 –MSG
44 –SEL
46 –C/D
48 –REQ
50 –I/O
1
1. The +5V drive supply is available on the SCSI connector as a terminator power
option. This pin is connected to the +5V through a diode. The option is selected
by a jumper at the rear of internal drives. Terminator power disabled is the
factory default.
2. ANSI defines –RST as a bidirectional pin. On the drive, –RST is input only.
Page 18 DAT Drives
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