Seagate BARRACUDA 180 User Manual
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Barracuda 180 Famil y:
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ST1181677LW/LWV/LC/LCV
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Product Manual, Volume 1
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Barracuda 180 Famil y:
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ST1181677LW/LWV/LC/LCV
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Product Manual, Volume 1
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© 2000-2001 Seagate Technology LLC All rights reserved
Publication number: 100109939, Rev. C
March 2001
Seagate, Seagate Technology, and the Seagate logo are registered trademarks of Seagate Technology LLC.
Barracuda, SeaFAX, SeaFONE, SeaBOARD, and SeaTDD are either registered trademarks or trademarks of
Seagate Technology LLC. 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 publica-
tion may be reproduced in any form without written permission ofSeagate Technology LLC.
Revision status summary sheet
Revision Date Writer/Engineer Sheets Affected
Rev. A (Class A Release) 11/9/2000 L. Newman/J. Nowitzke 1/1, v thru viii, 1-74.
Rev. B 1/17/2001 L. Newman/J. Nowitzke Page 26.
Rev. C 3/30/2001 L. Newman/J. Nowitzke Pages 21, 26, and 28.
Notice.
Product Manual 100109939 is Volume 1 of a two volume document with the SCSI interface information
in the SCSI Interface Product Manual, Volume 2, part number 75789509.
If you need the SCSI interface information, order the SCSI Interface Product Manual, Volume 2,
part number 75789509.
Barracuda 180 Product Manual, Rev. C v
Contents
1.0 Scope..........................................................................1
2.0 Applicable standards and reference documentation. . . .................................3
2.1 Standards. . . ..............................................................3
2.1.1 Electromagnetic compatibility . . . . . . . . . .................................3
2.1.2 Electromagnetic susceptibility. . . . . . . . . .................................3
2.2 Electromagnetic compliance . .................................................3
2.3 Reference documents .. . . . . .................................................4
3.0 Generaldescription...............................................................5
3.1 Standard features. . . . . . . . . . .................................................7
3.2 Mediacharacteristics........................................................7
3.3 Performance...............................................................7
3.4 Reliability.................................................................7
3.5 Unformattedandformattedcapacities...........................................8
3.6 Programmabledrivecapacity..................................................8
3.7 Factoryinstalledaccessories..................................................8
3.8 Options(factoryinstalled).....................................................8
3.9 Accessories(userinstalled)...................................................8
4.0 Performance characteristics . . . . . . .................................................9
4.1 Internaldrivecharacteristics(transparenttouser)..................................9
4.2 SCSIperformancecharacteristics(visibletouser) .................................9
4.2.1 Accesstime .......................................................9
4.2.2 Formatcommandexecutiontime(minutes)...............................9
4.2.3 Generalized performance characteristics .................................9
4.3 Start/stoptime ............................................................10
4.4 Prefetch/multi-segmentedcachecontrol........................................10
4.5 Cacheoperation...........................................................10
4.5.1 Cachingwritedata .................................................11
4.5.2 Prefetch operation ................................................. 12
5.0 Reliability specifications . . . . . . . . . ................................................13
5.1 Errorrates ...............................................................13
5.1.1 Environmentalinterference...........................................13
5.1.2 Read errors. . . . . . . ................................................13
5.1.3 Writeerrors.......................................................13
5.1.4 Seekerrors.......................................................13
5.2 Reliabilityandservice.......................................................14
5.2.1 Meantimebetweenfailure...........................................14
5.2.2 Fieldfailureratevs.time.............................................14
5.2.3 Preventivemaintenance.............................................15
5.2.4 Servicelife.......................................................15
5.2.5 Servicephilosophy................................................. 15
5.2.6 Servicetools......................................................15
5.2.7 HotpluggingBarracuda180discdrives.................................15
5.2.8 S.M.A.R.T. .......................................................16
5.2.9 DriveSelfTest(DST)...............................................17
5.2.10 Productwarranty...................................................18
6.0 Physical/electricalspecifications ..................................................21
6.1 ACpowerrequirements.....................................................21
6.2 DC power requirements . . . . . ................................................21
6.2.1 Conductednoiseimmunity...........................................22
6.2.2 Powersequencing .................................................22
6.2.3 12V-Currentprofile ...............................................22
6.3 Powerdissipation..........................................................24
6.4 Environmentallimits........................................................25
vi Barracuda 180 Product Manual, Rev. C
6.4.1 Temperature ......................................................25
6.4.2 Relativehumidity...................................................25
6.4.3 Effectivealtitude(sealevel)...........................................26
6.4.4 Shockandvibration.................................................26
6.4.5 Aircleanliness.....................................................28
6.4.6 Acoustics.........................................................28
6.4.7 Electromagneticsusceptibility.........................................28
6.5 Mechanicalspecifications....................................................29
7.0 Defectanderrormanagement .....................................................31
7.1 Driveinternaldefects........................................................31
7.2 Drive error recovery procedures . . . ............................................31
7.3 SCSIsystemserrors........................................................32
8.0 Installation .....................................................................33
8.1 DriveID/optionselectheader .................................................33
8.1.1 NotesforFigures12,13,and14. ......................................36
8.1.2 Functiondescription.................................................37
8.2 Driveorientation ...........................................................38
8.3 Cooling ..................................................................38
8.4 Drivemounting ............................................................39
8.5 Grounding................................................................39
9.0 Interfacerequirements............................................................41
9.1 Generaldescription.........................................................41
9.2 SCSIinterfacemessagessupported............................................41
9.3 SCSIinterfacecommandssupported...........................................42
9.3.1 InquiryVitalProductdata.............................................45
9.3.2 ModeSensedata...................................................46
9.4 SCSIbus conditions and miscellaneous features supported . . . . . . . . . . ...............48
9.5 Synchronousdatatransfer ...................................................49
9.5.1 Synchronous data transfer periods supported.............................49
9.5.2 REQ/ACKoffset....................................................49
9.6 Physical interface ..........................................................49
9.6.1 DCcableandconnector .............................................49
9.6.2 SCSIinterfacephysicaldescription.....................................51
9.6.3 SCSIinterfacecablerequirements .....................................51
9.6.4 Mating connectors . . . . . . ............................................52
9.7 Electricaldescription........................................................60
9.7.1 Multimode—SEandLVDalternatives...................................60
9.8 Terminatorrequirements.....................................................62
9.9 Terminatorpower ..........................................................62
9.10 DiscdriveSCSItiming.......................................................63
9.11 DriveactivityLED ..........................................................64
10.0 Seagate Technology support services. . . ............................................65
Barracuda 180 Product Manual, Rev. C vii
List of Figures
Figure 1. Barracuda 180 family drive (ST1181677LW shown) . . . . . . . . . . . . ....................1
Figure2. Barracuda180familydrive....................................................6
Figure3. TypicalBarracuda180familydrive+12Vcurrentprofile............................22
Figure 4. Typical Barracuda 180 SCSI SE mode +5 V current profile. . . . . . . ...................23
Figure 5. Typical Barracuda 180 SCSI LVD mode +5 V current profile. . . . . . ...................23
Figure6. DCcurrentandpowervs.input/outputoperationspersecond(single-endedmode)......24
Figure7. DCcurrentandpowervs.input/outputoperationspersecond(LVDmode).............24
Figure8. LocationoftheHDAtemperaturecheckpoint....................................25
Figure9. Recommendedmounting....................................................27
Figure 10. ST1181677LW/LWV mounting configuration dimensions . . . . . . . . ...................29
Figure 11. ST1181677LC/LCV mounting configuration dimensions . . . . . . . . . ...................30
Figure12. J6jumperheader..........................................................34
Figure13. J5jumperheader(onLW/LWVmodelsonly).....................................35
Figure14. J2optionselectheader.....................................................36
Figure15. Suggestedairflow.........................................................38
Figure 16. ST1181677LW/LWV drive physical interface (68-pin J1 SCSI I/O connector). . . . . . ......50
Figure 17. ST1181677LC/LCV drive physical interface (80-pin J1 SCSI I/O connector) . . . . . . ......50
Figure 18. SCSI daisy chain interface cabling for LW/LWV drives . . . . . . . . . . ...................53
Figure19. Nonshielded68pinSCSIdeviceconnectorusedonLW/LWVdrives..................54
Figure 20. Nonshielded 80 pin SCSI “SCA-2” connector,usedonLC/LCVdrives.................55
Figure21. LVDoutputsignals.........................................................61
Figure22. TypicalSE-LVDalternativetransmitterreceivercircuits ............................61
Barracuda 180 Product Manual, Rev. C 1
1.0 Scope
This manual describes Seagate Technology®LLC, Barracuda 180™ disc drives.
Barracuda 180 drives support the small computer system interface as described in the ANSI SCSI SPI-3 inter-
face specifications to the extent described in this manual. The
75789509) describes general SCSI interface characteristics of this and other families of Seagate drives.
From this point on in this product manual the reference to Barracuda 180 models is referred to as “the drive”
unless references to individual models are necessary.
SCSI Interface Product Manual
(part number
Figure 1. Barracuda 180 family drive (ST1181677LW shown)
2 Barracuda 180 Product Manual, Rev. C
Barracuda 180 Product Manual, Rev. C 3
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. In particular, the drive must be securely mounted in order to guarantee the specified performance characteristics. Mounting by bottom holes must meet the requirements of Section 8.4.
2.1 Standards
The Barracuda 180 family complies with Seagate standards as noted in the appropriate sections of this Manual
and the Seagate
The Barracuda 180 disc drive is a UL recognized component per UL1950, CSA certified to CSA C22.2 No.
950-M89, and VDE certified to VDE 0805 and EN60950.
2.1.1 Electromagnetic compatibility
The drive, as delivered, is designed for system integration and installation into a suitable enclosure prior to use.
As such the drive is supplied as a subassembly and is not subject to Subpart B of Part 15 of the FCC Rules
and Regulations nor the Radio Interference Regulations of the Canadian Department of Communications.
The design characteristics of the drive serve to minimize radiation when installed in an enclosure that provides
reasonable shielding. As such, the drive is capable of meeting the Class B limits of the FCC Rules and Regulations of the Canadian Department of Communications when properly packaged. However, it is the user’s
responsibility to assure that the drive meets 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.
SCSI Interface Product Manual
.
2.1.2 Electromagnetic susceptibility
As a component assembly, the drive is not required to meet any susceptibility performance requirements. It is
the responsibility of those integrating the drive within their systems to perform those tests required and design
their system to ensure that equipment operating in the same system as the drive or external to the system
does not adversely affect the performance of the drive. See Section 5.1.1 and Table 2, DC power requirements.
2.2 Electromagnetic compliance
Seagate uses an independent laboratory to confirm compliance to the directives/standard(s) for CE Marking
and C-Tick Marking. The drive was tested in a representative system for typical applications. The selected system represents the most popular characteristics for test platforms. The system configurations include:
• Typical current use microprocessors
• 3.5-inch floppy disc drive
• Keyboard
• Monitor/display
• Printer
• External modem
• Mouse
Although the test system with this Seagate model complies to the directives/standard(s), we cannot guarantee
that all systems will comply. The computer manufacturer or system integrator must confirm EMC compliance
and provide CE Marking and C-Tick Marking for their product.
Electromagnetic compliance for the European Union
If this model has the CE Marking it complies with the European Union requirements of the Electromagnetic
Compatibility Directive 89/336/EEC of 03 May 1989 as amended by Directive 92/31/EEC of 28 April 1992 and
Directive 93/68/EEC of 22 July 1993.
4 Barracuda 180 Product Manual, Rev. C
Australian C-Tick
If this model has the C-Tick Marking it complies with the Australia/New Zealand Standard AS/NZS3548 1995
and meets the Electromagnetic Compatibility (EMC) Framew ork requirements of Australia’s Spectrum Management Agency (SMA).
Korean MIC
If this model has the MIC (Ministry of Information and Communication) Marking it complies with paragraph 1 of
Article 11 of the Electromagnetic Compatibility control Regulation and meets the Electromagnetic Compatibility
(EMC) Framework requirements of the Radio Research Laboratory Ministry of Information and Communication
Republic of Korea.
Taiwan MIC
If this model has two Chinese words meaning “EMC certification” followed by an eight digit identification number, as a Marking, it complies with Chinese National Standard (CNS) 13438 and meets the Electromagnetic
Compatibility (EMC) Framework requirements of the Taiwanese Bureau of Standards, Metrology, and Inspection (BSMI).
2.3 Reference documents
Barracuda 180 Installation Guide
Safety and Regulatory Agency Specifications
SCSI Interface Product Manual
ANSI small computer system interface (SCSI) document numbers:
T10/1143D Enhanced SCSI Parallel Interface (EPI)
T10/1236D Primary Commands-2 (SPC-2)
T10/996D SCSI Block Commands (SBC)
T10/1157D SCSI Architectural Model-2 (SAM-2)
T10/1302D SCSI Parallel Interface version 3 (SPI-3)
SFF-8451, Specification for SCA-2 Unshielded Connections
Package Test Specification Seagate P/N 30190-001 (under 100 lb.)
Package Test Specification Seagate P/N 30191-001 (over 100 lb.)
Specification, Acoustic Test Requirements, and Procedures Seagate P/N 30553-001
In case of conflict between this document and any referenced document, this document takes precedence.
Seagate P/N 100109942
Seagate P/N 75789512
Seagate P/N 75789509
Barracuda 180 Product Manual, Rev. C 5
3.0 General description
Barracuda 180 drives combine giant magnetoresistive (GMR) heads, partial response/maximum likelihood
(PRML) read channel electronics, embedded servo technology, and a wide Ultra160 SCSI interface to provide
high performance, high capacity data storage for a variety of systems including engineering workstations, network servers, mainframes, and supercomputers.
The Ultra160 SCSI interface uses negotiated transfer rates. These transfer rates will occur only if your host
adapter supports these data transfer rates and is compatible with the required hardware requirements of the I/
O circuit type. This drive can also operate at SCSI-1 and SCSI-2 data transfer rates for backward compatibility
with non-Ultra/Ultra2/Ultra160 SCSI host adapters.
Table 1 lists the features that differentiate the various Barracuda 180 models.
Table 1: Drive model number vs. differentiating features
Number of I/O
Data buffer
Model number
size I/O circuit type [1]
ST1181677LW 4,096 kbytes Single-ended (SE) and low voltage differential (LVD) 68
ST1181677LWV 16,384 kbytes Single-ended (SE) and low voltage differential (L VD) 68
ST1181677LC 4,096 kbytes Single-ended (SE) and low voltage differential (LVD) 80
connector
pins
ST1181677LCV 16,384 kbytes Single-ended (SE) and low voltage differential (LVD) 80
[1] See Section 9.6 for details and definitions.
The drive records and recovers data on approximately 3.3-inch (84 mm) non-removable discs.
The drive supports the Small Computer System Interface (SCSI) as described in the ANSI SCSI-2/SCSI-3
interface specifications to the extent described in this manual (volume 1), which defines the product performance characteristics of the Barracuda 180 family of drives, and the
SCSI Interface Product Manual
,which
describes the general interface characteristics of this and other families of Seagate SCSI drives.
The drive’s interface supports multiple initiators, disconnect/reconnect, self-configuring host software, and
automatic features that relieve the host from the necessity of knowingthe physical characteristics of the targets
(logical block addressing is used).
The head and disc assembly (HDA) is sealed at the factory. Air circulates within the HDA through a nonreplaceable filter to maintain a contamination-free HDA environment.
Refer to Figure 2 for an exploded view of the drive. This exploded view is for information only—never disassemble the HDA and do not attempt to service items in the sealed enclosure (heads, media, actuator, etc.) as this
requires special facilities. The drive contains no replaceable parts. Opening the HDA voids your warranty.
Barracuda 180 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 power is removed.
An automatic shipping lock prevents potential damage to the heads and discs that results from movement during shipping and handling. The shipping lock automatically disengages when power is applied to the drive and
the head load process begins.
Barracuda 180 drives decode track 0 location data from the servo data embedded on each surface to eliminate
mechanical transducer adjustments and related reliability concerns.
A high-performance actuator assembly with a low-inertia, balanced, patented, straight-arm design provides
excellent performance with minimal power dissipation.
6 Barracuda 180 Product Manual, Rev. C
Figure 2. Barracuda 180 family drive
Barracuda 180 Product Manual, Rev. C 7
3.1 Standard features
The Barracuda 180 family has the following standard features:
• Integrated Ultra160 SCSI controller
• Multimode SCSI drivers and receivers—single-ended (SE) and low voltage differential (LVD)
• 16 bit I/O data bus
• Asynchronous and synchronous data transfer protocol (supports Ultra160 transfer rate)
• Firmware downloadable via SCSI interface
• Selectable even byte sector sizes from 512 to 4,096 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)
• EnhancedECC (maximumburst correctionslength of 240 bits with a guaranteed burst correction of 233 bits)
• Sealed head and disc assembly
• No preventative maintenance or adjustment required
• Dedicated head landing zone
• Embedded servo design
• Self diagnostics performed when power is applied to the drive
• Zoned bit recording (ZBR)
• Vertical, horizontal,or top down mounting
• Dynamic spindle brake
• 4,096 kbyte data buffer (16,384 kbytes on LWV and LCV models)
• Hot plug compatibility for LC and LCV model drives (Section 9.6.4.2 lists proper host connector needed)
• Supports SCSI bus fairness
3.2 Media characteristics
The media used on the drive has a diameter of approximately 3.3 inches (84 mm). The aluminum substrate is
coated with a thin film magnetic material, overcoated with a proprietary protective layer for improved durability
and environmental protection.
3.3 Performance
• Supports industry standard Ultra160 SCSI interface
• Programmable multi-segmentable cache buffer (see Section 3.1)
• 7,200 RPM spindle. Average latency = 4.17 ms
• Command queuing of up to 64 commands
• Background processing of queue
• Supports start and stop commands (spindle stops spinning)
3.4 Reliability
• 1,200,000 hour MTBF
• LSI circuitry
• Balanced low mass rotary voice coil actuator
• Incorporates industry-standard Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T.)
• Incorporates Drive Self Test (DST) technology
• 5-year warranty
8 Barracuda 180 Product Manual, Rev. C
3.5 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 the standard OEM model capacities:
Formatted
data block size
512 bytes/sector [1] Unformatted
ST1181677 1522c441h (181.6 GB) [2] 241.9 GB
Notes.
[1] Sector size selectable at format time. Users having the necessary equipment may modify the data block
size before issuing a format command and obtain different formatted capacities than those listed. See
Mode Select Command and Format Command in the
SCSI Interface Product Manual
.
[2] User available capacity depends on spare reallocation scheme selected, the number of data tracks per
sparing zone, and the number of alternate sectors (LBAs) per sparing zone.
3.6 Programmable drive capacity
Using the Mode Select command, you can change the drive’s capacity to something less than maximum. See
SCSI Interface Product Manual
the
. Refer to the Parameter list block descriptor number of blocks field. A value
of zero in the number of blocks field indicates that the drivewill not change the capacity it is currently formatted
to have. A number in the number of blocks field that is less than the maximum number of LBAs changes the
total drive capacity to the value in the block descriptor number of blocks field. A value greater than the maximum number of LBAs is rounded down to the maximum capacity.
3.7 Factory installed accessories
OEM standard drives are shipped with the
Safety and Regulatory Agency Specifications
Barracuda 180 Installation Guide
, part number 100109942 and the
, part number 75789512 (unless otherwise specified). A small
bag of jumper plugs used for the J2, J5, and J6 option select jumper headers are also included with the drive.
3.8 Options (factory installed)
All customer requested options are incorporated during production or packaged at the manufacturing facility
before shipping. Some of the options available are (not an exhaustive list of possible options):
• Other capacities can be ordered depending on sparing scheme and sector size requested.
• Single unit shipping pack. The drive is normally shipped in bulk packaging to provide maximum protection
against transit damage. Units shipped individually require additional protection as provided by the single unit
shipping pack. Users planning single unit distribution should specify this option.
• The
Barracuda 180 Installation Guide
, part number 100109942. This guide is usually included with each
standard OEM drive shipped, but you may order extra copies.
• The
Safety and Regulatory Agency Specifications
, part number 75789512, is usually included with each
standard OEM drive shipped, but you may order extra copies.
3.9 Accessories (user installed)
The followingaccessories are available. All accessories may be installed in the field.
• Single unit shipping pack.
Barracuda 180 Product Manual, Rev. C 9
4.0 Performance characteristics
4.1 Internal drive characteristics (transparent to user)
ST1181677
Drive capacity 181.6 GBytes (formatted, rounded off values)
Read/write heads 24
Bytes/track 406,071 Bytes (average, rounded off values)
Bytes/surface 19,263 Mbytes (unformatted, rounded off values)
Tracks/surface (total) 24,247 Tracks (user accessible)
Tracks/inch 31,200 TPI
Peak bits/inch 490 KBPI
Internal data rate 282-508 Mbits/sec (variable with zone)
Disc rotational speed 7,200 r/min (+
Average rotational latency 4.17 msec
4.2 SCSI performance characteristics (visible to user)
The values given in Section 4.2.1 apply to all models of the Barracuda 180 family unless otherwise specified.
Refer to Section 9.10 and to the
SCSI Interface Product Manual
4.2.1 Access time [5]
Including controller overhead
(without disconnect) [1] [3]
Drive level Drive level
Read Write Read Write
msec msec
Av erage—Typical [2] 7.6 8.4 7.4 8.2
Single Track—Typical [2] 1.0 1.3 0.8 1.1
Full Stroke—Typical [2] 16.2 17.2 16.0 17.0
0.5%)
for additional timing details.
Not Including controller overhead
(without disconnect) [1] [3]
4.2.2 Format command execution time (minutes) [1]
ST1181677
Maximum (with verify) 210
Maximum (no verify) 120
4.2.3 Generalized performance characteristics
Minimum sector interleave 1 to 1
Data buffer transfer rate to/from disc media (one 512-byte sector):
Minimum [3]* 25.3 MByte/sec
Average [3] 36.1 MByte/sec
Maximum [3] 47.0 MByte/sec
SCSI interface data transfer rate (asynchronous):
Maximum instantaneous one byte wide 5.0 Mbytes/sec [4]
Maximum instantaneous two bytes wide 10.0 Mbytes/sec [4]
Synchronous formatted transfer rate Ultra2 SCSI Ultra160 SCSI
In low voltage differential (LVD) interface mode 5.0 to 80 Mbytes/sec 5.0 to 160 Mbytes/sec
10 Barracuda 1 80 Product Manual, Rev. C
Sector Sizes:
Default 512 byte user data blocks
Variable 512 to 4,096 bytes per sector in even number of bytes per sector.
If n (number of bytes per sector) is odd, then n-1 will be used.
Read/write consecutive sectors on a track Yes
Flaw reallocation performance impact (for flaws reallocated at format time using
the spare sectors per sparing zone reallocation scheme.)
Average rotational latency 4.17 msec
Notes for Section 4.2.
[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 connect/disconnect).
[2] Typical access times are measured under nominal conditions of temperature, voltage, and horizontal ori-
entation as measured on a representative sample of drives.
[3] Assumes no errors and no sector has been relocated.
[4] Assumes system ability to support the rates listed and no cable loss.
[5] Access time = controller overhead + average seek time.
Access to data = controller overhead + average seek time + latency time.
4.3 Start/stop time
After DC power at nominal voltage has been applied, the drive becomes ready within 30 seconds if the Motor
Start Option is disabled (i.e. the motor starts as soon as the power has been applied). If a recoverable error
condition is detected during the start sequence, the drive executes a recovery procedure which may cause the
time to become ready to exceed 30 seconds. During spin up to ready time the drive responds to some commands over the SCSI interface in less than 1.5 seconds after application of power. Stop time is less than 30
seconds from removal of DC power.
If the Motor Start Option is enabled, the internal controller accepts the commands listed in the
Product Manual
been received the drive becomes ready for normal operations within 30 seconds typically (excluding an error
recovery procedure). The Motor Start Command can also be used to command the drive to stop the spindle
(see
SCSI Interface Product Manual
less than 1.5 seconds after DC power has been applied. After the Motor Start Command has
).
Negligible
SCSI Interface
There is no power control switch on the drive.
4.4 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. “The term “cache” 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 (see
and cache operations are independent features from the standpoint that each is enabled and disabled independently using the Mode Select command. However, in actual operation, the prefetch feature overlaps cache
operation somewhat as is noted in Section 4.5.1 and 4.5.2.
All default cache and prefetch Mode parameter values (Mode Page 08h) for standard OEM versions of this
drive family are provided in Table 7.
4.5 Cache operation
In general, 3,600 kbytes (14,399 kbytes of the 16,384 kbytes on LWV and LCV models) of the 4,096 kbytes of
physical buffer space in the drive can be used as storage space for cache operations. The buffer can be divided
into logical segments (Mode Select Page 08h, byte 13) from which data is read and to which data is written.
The drive supports a maximum of 64 cache segments and maintains a table of logical block disk medium
addresses of the data stored in each segment of thebuffer. If cache operation is enabled (RCD bit = 0 in Mode
Page 08h, byte 2, bit 0. See
mand is retrieved from the buffer (if it is there) before any disc access is initiated. If cache operation is not
SCSI Interface Product Manual
), data requested by the host with a Read com-
SCSI Interface Product Manual)
.Prefetch
Barracuda 180 Product Manual, Rev. C 11
enabled, the buffer (still segmented with required number of segments) is still used, but 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 buffer segments for the requested read data, but goes directly to the medium to
retrieve it. The retrieved data merely passes through some buffer segment on the way to the host. On a cache
miss, all data transfers to the host are in accordance with buffer-full ratio rules. On a cache hit, the drive ignores
the buffer-full ratio rules. See explanations associated with Mode page 02h (disconnect/reconnect control) in
the
SCSI Interface Product Manual
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. Driv e transfers to the initiator the first LB requested plus all subsequent contiguous LBs 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 drivefetches it and any remaining
requested LBs from the disc and puts them in a segment of the cache. The drive transfers the remaining
requested LBs 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 4.5.2 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 drivefetches the requested LBs from the disc and transfers them into a segment, and from there to the
host in a ccordance with the disconnect/reconnect specification referred to in case A.
2. If the prefetch feature is enabled, refer to Section 4.5.2 for operation from this point.
.
Each buffer segment is a self-contained circular storage area (wrap-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 cache storage, allowing a wide range of user selectable configurations, including their use in the prefetch operation (if enabled) even when cache operation is disabled (see
Section4.5.2). The numberof segmentsis set dynamically by the drive and cannot be set by the host.The size
in kbytes of each segment is not reported by the Mode Sense command page 08h, bytes 14 and 15. The value
0XFFFF is always reported. 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
Product Manual
three segments.
4.5.1 Caching write data
Write caching is a write operation that uses the drive buffer 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.
If read caching is enabled (RCD=0), data written to the medium is retained in the cache for future read cache
hits. The same buffer 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 the state of the RCD bit. When a write
command is issued, if RCD=0, 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.
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. However, the drive does not overwrite data that has not
yet been written to the medium.
). The drive supports operation of any integer number of segments from 1 to 64. The default is
SCSI Interface
If write caching is enabled (WCE=1), the drive may return GOOD status on a write command after the data has
been transferred into the cache, but before the data has been written to the medium. If an error occurs while
writing the data to the medium, and GOOD status has already been returned, a deferred error will occur.
The Synchronize Cache command may be used to force the drive to write all cached write data to the medium.
Upon completion of a Synchronize Cache command, all data received from previous write commands will have
been written to the medium.
12 Barracuda 1 80 Product Manual, Rev. C
Tables 7 show Mode default settings for the drives.
4.5.2 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 retrieved and stored in the buffer 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 max prefetch field (bytes 8 and 9) limits the amount of prefetch. The drive does not use the
Prefetch Ceiling field (bytes 10 and 11).
During a prefetch operation, the drive crosses a cylinder boundary to fetch more data only if the Discontinuity
(DISC) bit is set to one in bit 4 of byte 2 of Mode parameters page 08h.
Whenever prefetch (read look-ahead) is enabled (enabled by DRA = 0), it operates under the control of ARLA
(Adaptive Read Look-Ahead). If the host uses software interleave, ARLA enablesprefetch of contiguous blocks
from the disc when it senses that a prefetch hit will likely occur, even if two consecutive read operations were
not for physically contiguous blocks of data (e.g. “software interleave”). ARLA disables prefetch when it decides
that a prefetch hit will not likely occur. If the host is not using software interleave, and if two sequential read
operations are not for contiguous blocks of data, ARLA disables prefetch, but as long as sequential read operations request contiguous blocks of data, ARLA keeps prefetch enabled.
Barracuda 180 Product Manual, Rev. C 13
5.0 Reliability specifications
The following reliability specifications assume correct host/drive operational interface, including all interface
timings, power supply voltages, environmental requirements and drive mounting constraints (see Section 8.4).
Seek Errors
Less than 10 in 10
Read Error Rates [1]
Recovered Data Less than 10 errors in 10
Unrecovered Data Less than 1 sector in 10
Miscorrected Data Less than 1 sector in 10
MTBF 1,200,000 hours
Service Life 5 years
Preventive Maintenance None required
Note.
[1] Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated.
5.1 Error rates
The error rates stated in this specification assume the following:
• The drive is operated per this specification using DC power as defined in this manual (see Section 6.2).
• The drive has beenfo rmatted with the SCSI Format command.
• Errors caused by media defects or host system failures are excluded from error rate computations. Refer to
Section 3.2, “Media Characteristics.”
• Random data is used.
8
seeks
12
bits transferred (OEM defaultsettings)
15
bits transferred (OEM defaultsettings)
21
bits transferred
5.1.1 Environmental interference
When evaluating system operation under conditions of Electromagnetic Interference (EMI), the performance of
the drive within the system is considered acceptable if the drive does not generate an unrecoverable condition.
An unrecoverable error, or unrecoverable condition, is defined as one that:
• Is not detected and corrected by the drive itself;
• Is not capable of being detected from the error or fault status provided through the drive or SCSI interface; or
• Is not capable of being recovered by normal drive or system recovery p rocedures without operator interven-
tion.
5.1.2 Read errors
Before determination or measurement of read error rates:
• The data to be used for measurement of read error rates must be verified as being written correctly on the
media.
• All media defect induced errors must be excluded from error rate calculations.
5.1.3 Write errors
Write errors can occur as a result of media defects, environmental interference, or equipment malfunction.
Therefore, write errors are not predictable as a function of the number of bits passed.
If an unrecoverable write error occurs because of an equipment malfunction in the drive, the error is classified
as a failure affecting MTBF. Unrecoverable write errors are those which cannot be corrected within two
attempts at writing the record with a read verify after each attempt (excluding media defects).
5.1.4 Seek errors
A seek error is defined as a failure of the drive to position the heads to the addressed track. There shall be no
more than ten recoverable seek errors in 10
8
physical seek operations. After detecting an initial seek error, the
drive automatically performs an error recovery process. If the error recovery process fails, a seek positioning
error (15h) is reported with a Medium error (3h) or Hardware error (4h) reported in the Sense Key. This is an
14 Barracuda 1 80 Product Manual, Rev. C
unrecoverable seek error. Unrecoverable seek errors are classified as failures for MTBF calculations. Refer to
the
SCSI Interface Product Manual
for Request Sense information.
5.2 Reliability and service
You can enhance the reliability of Barracuda180 disc drives by en suring that thedrive receives adequate cooling. Section 6.0 provides temperature measurements and other information that you can use to enhance the
service life of the drive. Section 8.3 provides recommended air-flow information.
5.2.1 Mean time between failure
The production disc drive achieves an MTBF of 1,200,000 hours when operated in an environment that
ensures the case temperatures specified in Section 6.4.1 are not exceeded. Short-term excursions up to the
specification limits of the operating environment will not affect MTBF performance. Continual or sustained
operation at case temperatures above the values specified in Section 6.4.1 may degrade product reliability.
The MTBF target is specified as device power-on hours (POH) for all drives in service per failure.
MTBF per measurement period =
Estimated power-on operating hours in the period
__
Number of drive failures in the period
Estimated power-on operation hours means power-up hours per disc drive times the total number of disc drives
in service. Each disc drive must have accumulated at least nine months of operation. Data is calculated on a
rolling average base for a minimum period of six months.
MTBF is based on the following assumptions:
• 8,760 power-on hours per year.
• 250 average on/off cycles per year.
• Operations at nominal voltages.
• Systems will provide adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not
exceeded.
Drive failure means any stoppage or substandard performance caused by drive malfunction.
A S.M.A.R.T. predictive failure indicates that the drive is deteriorating to an imminent failure and is considered
an MTBF hit.
5.2.2 Field failure rate vs. time
The expected field failure rate is listed below. D rive utilization will vary. An estimated range of utilization is:
• 720 power-on hours (POH) per month.
• 250 on/off cycles per year.
• Read/seek/write operation 90% of power-on hours.
• Systems will provide adequate cooling to ensure the case temperatures specified in Section 6.4.1 are not
exceeded.
Month 1 2,500 PPM
Month 2 1,600 PPM
Month 3 1,200 PPM
Month 4 1,000 PPM
Month 5 890 PPM
Month 6 840 PPM
Month 7 805 PPM
Failure rate is calculated as follows:
• No system-induced failures are counted
• Based on 1,200,000 MTBF and 720 power-on hours per month
• Month 1’s rate includes a 300 PPM installation failure
Barracuda 180 Product Manual, Rev. C 15
5.2.3 Preventive maintenance
No preventive maintenance is required.
5.2.4 Service life
The useful service life of the drive is five years. Depot repair or replacement of major parts is permitted during
the lifetime (see Section 5.2.5).
5.2.5 Service philosophy
Special equipment is required to repair the drive HDA. In order to achieve the above service life, repairs must
be performed only at a properly equipped and staffed service and repair facility. Troubleshooting and repair of
PCBs in the field is not recommended, because of the extensive diagnostic equipment required for effective
servicing. Also, there are no spare parts available for this drive. Drive warranty is voided if the HDA is opened.
5.2.6 Service tools
No special tools are required for site installation or recommendedfor site maintenance. Refer to Section 5.2.5.
The depot repair philosophy of the drive precludes the necessity for special tools. Field repair of the drive is not
practical since there are no user purchasable parts in the drive.
5.2.7 Hot plugging Barracuda 180 disc drives
The ANSI SPI-3 (T10/1302D) document defines the physical requirements for removal and insertion of SCSI
devices on the SCSI bus. Four cases are addressed. The cases are differentiated by the state of the SCSI bus
when the removal or insertion occurs.
Case 1 - All bus devices powered off during removal or insertion
Case 2 - RST signal asserted continuously during removal or insertion
Case 3 - Current I/O processes not allowed during insertion or removal
Case 4 - Current I/O process allowed during insertion or removal,except on the device being changed
Seagate Barracuda 180 disc drives support all four hot plugging cases. Provision should be made by the system such that a device being inserted makes power and ground connections prior to the connection of any
device signal contact to the bus. A device being removed should maintain power and ground connections after
the disconnection of any device signal contact from the bus (see T10/1302D SPI-3 Annex C).
It is the responsibility of the systems integrator to assure that no hazards from temperature, energy, voltage, or
ESD potential are presented during the hot connect/disconnect operation.
All I/O processes for the SCSI device being inserted or removed should be quiescent. All SCSI devices on the
bus should have receivers that conform to the SPI-3 standard.
If the device being hot plugged uses single-ended (SE) drivers and the bus is currently operating in low voltage
differential (LVD) mode, then all I/O processes for all devices on the bus must be completed, and the bus quiesced before attempting to hot plug the drive. Following the insertion of the newly installed device, the SCSI
host adapter must issue a Bus Reset, followed by a synchronous transfer negotiation. Failure to perform the
SCSI Bus Reset could result in erroneous bus operations.
The SCSI bus termination and termination power source must be external to the device being inserted or
removed.
End users should not mix devices with high voltage differential (HVD) drivers and receivers and devices with
SE, LVD, or multimode drivers and receivers on the same SCSI bus since the common mode voltages in the
HVD environment may not be controlled to safe levels for SE and L VD devices (see ANSI SPI-3).
The disc drive spindle must come to a complete stop prior to completely removing the drive from the cabinet
chassis. Use of the Stop Spindle command or partial withdrawal of the drive, enough to be disconnected from
the power source, prior to removal are methods for insuring that this requirement is met. During drive insertion,
care should be taken to avoid exceeding the limits stated in Section 6.4.4, “Shock and vibration” in this manual.
16 Barracuda 1 80 Product Manual, Rev. C
5.2.8 S.M.A.R.T.
S.M.A.R.T. is an acronym for Self-Monitoring Analysis and Reporting Technology. This technology is intended
to recognize conditions that indicate a drive failure and is designed to provide sufficient warning of a failure to
allow data back-up before an actual failure occurs.
Note. The firmware will monitor specific attributes for degradation over time but cannot predict instantaneous
drive failures.
Each attribute has been selected to monitor a specific set of failure conditions in the operating performance of
the drive, and the thresholds are optimized to minimize “false” and “failed” predictions.
Controlling S.M.A.R.T.
The operating mode of S.M.A.R.T. is controlled by the DEXCPT bit and the PERF bit of the “Informational
Exceptions Control Mode Page” (1Ch). The DEXCPT bit is used to enable or disable the S.M.A.R.T. process.
Setting the DEXCPT bit will disable all S.M.A.R.T. functions. When enabled, S.M.A.R.T. will collect on-line data
as the drive performs normal read/write operations. When the PERF bit is set, the drive is considered to be in
“On-line Mode Only” and will not perform off-line functions.
The process of measuring off-line attributes andsaving data can be forced by the RezeroUnit command. Forcing S.M.A.R.T. will reset the timer so that the next scheduled interrupt will be two hours.
The drive can be interrogated by the host to determine the time remaining before the next scheduled measurement and data logging process will occur. This is accomplished by a log sense command to log page 0x3E.
The purpose is to allow the customer to control when S.M.A.R.T. interruptions occur. As described above, forcing S.M.A.R.T by the Rezero Unit command will reset the timer.
Performance impact
S.M.A.R.T. attribute data will be saved to the disc for the purpose of recreating the events that caused a predictive failure. The drive will measure and save parameters once every two hours subject to an idle period on the
SCSI bus. The process of measuring off-line attribute data and saving data to the disc is uninterruptable and
the maximum delay is summarized below:
Maximum processing delay
On-line only delay Fully enabled delay
DEXCPT = 0, PERF = 1 DEXCPT = 0, PERF = 0
S.M.A.R.T. delay times 50 milliseconds 300 milliseconds
Reporting control
Reporting is controlled in the Informational Exceptions Control Page (1Ch). Subject to the reporting method,
the firmware will issue a 01-5D00 sense code to the host. The error code is preserved through bus resets and
power cycles.
Determining rate
S.M.A.R.T. monitors the rate at which errors occur and signals a predictive failure if the rate of degraded error
rate increases to an unacceptable level. To determine rate, error events are logged and compared to the number of total operations for a given attribute. The interval defines the number of operations over which to measure the rate. The counter that keeps track of the current number of operations is referred to as the Interval
Counter.
S.M.A.R.T. measures error rate, hence for each attribute the occurrence of an error is recorded. A counter
keeps track of the number of errors for the current interval. This counter is referred to as the Failure Counter.
Error rate is simply the number of errors per operation. The algorithm that S.M.A.R.T. uses to record rates of
error is to set thresholds for the number of errors and the interval. If the number of errors exceeds the threshold
before the interval expires, then the error rate is considered to be unacceptable. If the number of errors does
not exceed the threshold before the interval expires, then the error rate is considered to be acceptable. In either
case,the interval and failure counters are reset and the process starts over.
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