
S T 3 9 1 7 3 F C    SEAGATE
                                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 3.5"/SLIMLINE         Cylinders        |     |     |
Capacity form/unform  9100/      MB        Heads          10|     |     |
Seek time   / track   7.1/ 1.2 ms          Sector/track     |     |     |
Controller           SCSI3 FIBRE/SCA       Precompensation
Cache/Buffer          1024 KB MULTI-SEGMEN Landing Zone
Data transfer rate   15.000 MB/S int       Bytes/Sector      512
                    100.000 MB/S ext
Recording method     EPR4 16/17                     operating  | non-operating
                                                  -------------+--------------
Supply voltage     5 V          Temperature *C         5 50    |    -40 70
Power: sleep              W     Humidity     %         5 90    |      5 95
       standby            W     Altitude    km                 |
       idle          13.0 W     Shock        g        10       |     75
       seek               W     Rotation   RPM      7200
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit   ON THE FLY,SMART
                                MTBF         h    1000000
                                Warranty Month        60
Lift/Lock/Park     YES          Certificates


**********************************************************************
                      J   U   M   P   E   R   S
**********************************************************************
SEAGATE  ST39173FC


 Jumper Setting
 ==============

 Jumpers are not used on the drive.


 Drive ID/option selection
 -------------------------
 All drive options are made through the interface connector (J1).

 LED connections
 ---------------
 A connector, J6, is provided on the printed circuit board assembly
 (PCBA) to provide port bypass, drive active, and drive fault LED
 connections.


 J6 connector requirements
 -------------------------
 Recommended mating connector part number: Berg receptacle,
 6-position, Berg part number 690-006.



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                      I   N   S   T   A   L   L
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SEAGATE  ST39173FC  PRODUCT MANUAL 77767522, REV. B

 Notes on installation
 =====================

 Installation direction
 ----------------------

     horizontally                           vertically
   +-----------------+             +--+                       +--+
   |                 |             |  +-----+           +-----+  |
   |                 |             |  |     |           |     |  |
 +-+-----------------+-+           |  |     |           |     |  |
 +---------------------+           |  |     |           |     |  |
                                   |  |     |           |     |  |
                                   |  |     |           |     |  |
 +---------------------+           |  +-----+           +-----+  |
 +-+-----------------+-+           +--+                       +--+
   |                 |
   |                 |
   +-----------------+

 The drive will operate in all axis (6 directions).


 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.


 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.


 Electromagnetic compliance
 --------------------------
 Seagate uses an independent laboratory to confirm compliance with the
 directives/standards 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:

 - 486, Pentium, and PowerPC microprocessors
 - 3.5-inch floppy disc drive
 - Keyboard
 - Monitor/display
 - Printer
 - External modem
 - Mouse

 Although the test system with this Seagate model complies with the
 directives/standards, we cannot guarantee that all systems will
 comply. The computer manufacturer or system integrator shall confirm
 EMC compliance and provide the appropriate 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.


 Cache operation
 ---------------
 Note. Refer to the Fibre Channel Interface Manual for more detail
 concerning the cache bits. Of the 1,024 Kbytes physical buffer space
 in the drive, 967.5 Kbytes can be used as a cache.  The cache can
 be divided into logical segments from which data is read and to which
 data is written.

 The drive keeps track of the logical block addresses of the data
 stored in each segment of the cache. If the cache is enabled (see RCD
 bit in the Fibre Channel Interface Manual), data requested by the
 host with a read command is retrieved from the cache, if possible,
 before any disc access is initiated. Data in contiguous logical
 blocks immediately beyond that requested by the Read command can be
 retrieved and stored in the cache for immediate transfer to the
 initiator on subsequent read commands. This is referred to as the
 prefetch operation.

 Since data that is prefetched may replace data already in the cache
 segment, an initiator can limit the amount of prefetch data to
 optimize system performance. The drive never prefetches more sectors
 than the number specified in bytes 8 and 9 of Mode page 08h. If the
 cache is not enabled, 967.5 Kbytes of the buffer are used as
 a circular buffer for read/writes, with no prefetch operation and no
 segmented cache operation.


 Shipping
 --------
 When transporting or shipping a drive, use only a Seagate-approved
 container. Keep your original box.

 Seagate approved containers are easily identified by the Seagate
 Approved Package label. Shipping a drive in a non-approved container
 voids the drive warranty.

 Seagate repair centers may refuse receipt of components improperly
 packaged or obviously damaged in transit. Contact your authorized
 Seagate distributor to purchase additional boxes. Seagate
 recommends shipping by an air-ride carrier experienced in handling
 computer equipment.


 Hot plugging the drive
 ----------------------
 Inserting and removing the drive on the FC-AL will interrupt loop
 operation. The interruption occurs when the receiver of the next
 device in the loop must synchronize to a different input signal. FC
 error detection mechanisms, character sync, running disparity, word
 sync, and CRC are able to detect any error. Recovery is initiated
 based on the type of error.

 The disc drive defaults to the FC-AL Monitoring state, Pass-through
 state, when it is powered-on by switching the power or hot plugged.
 The control line to an optional port bypass circuit (external to the
 drive), defaults to the Enable Bypass state. If the bypass circuit is
 present, the next device in the loop will continue to receive the
 output of the previous device to the newly inserted device. If the
 bypass circuit is not present, loop operation is temporarily
 disrupted until the next device starts receiving the output from the
 newly inserted device and regains synchronization to the new input.

 The Pass-through state is disabled while the drive performs self test
 of the FC interface. The control line for an external port bypass
 circuit remains in the Enable Bypass state while self test is
 running. If the bypass circuit is present, loop operation may
 continue. If the bypass circuit is not present, loop operation will
 be halted while the self test of the FC interface runs.

 When the self test completes successfully, the control line to the
 bypass circuit is disabled and the drive enters the FC-AL
 Initializing state. The receiver on the next device in the loop must
 synchronize to output of the newly inserted drive.

 If the self-test fails, the control line to the bypass circuit
 remains in the Enable Bypass state.

 Note. It is the responsibility of the systems integrator to assure
 that no temperature, energy, voltage hazard, or ESD potential hazard
 is presented during the hot connect/disconnect operation. Discharge
 the static electricity from the drive carrier prior to inserting it
 into the system.

 Caution. The drive motor must come to a complete stop prior to
 changing the plane of operation. This time is required to insure data
 integrity.


 Shock and vibration
 -------------------
 Shock and vibration limits specified in this document are measured
 directly on the drive chassis. If the drive is installed in an
 enclosure to which the stated shock and/or vibration criteria are
 applied, resonances may occur internally to the enclosure resulting
 in drive movement in excess of the stated limits. If this situation
 is apparent, it may be necessary to modify the enclosure to minimize
 drive movement.

 The limits of shock and vibration defined within this document are
 specified with the drive mounted in a vertical or horizontal
 position.

 Shock
 -----
 a. Operating (normal)
 The drive, as installed for normal operation, will operate error free
 while subjected to intermittent shock not exceeding 2.0 Gs at a
 maximum duration of 11 msec (half sinewave). Shock may be applied in
 the X, Y, or Z axis.

 b. Operating (abnormal)
 Equipment as installed for normal operation will not incur physical
 damage while subjected to intermittent shock not exceeding 10 Gs at a
 maximum duration of 11 msec (half sinewave). Shock occurring at
 abnormal levels may promote degraded operational performance during
 the abnormal shock period. Specified operational performance will
 continue when normal operating shock levels resume. Shock may
 be applied in the X, Y, or Z axis. Shock is not to be repeated more
 than two times per second.

 c. Non-operating
 The limits of non-operating shock apply to all conditions of handling
 and transportation. This includes both isolated drives and integrated
 drives. The drive subjected to non-repetitive shock not exceeding 75
 Gs at a maximum duration of 11 msec (half sinewave) will not exhibit
 device damage or performance degradation. Shock may be applied in
 the X, Y, or Z axis.

 The drive subjected to non-repetitive shock not exceeding 140 Gs at a
 maximum of 2 msec (half sinewave) will not exhibit device damage or
 performance degradation. Shock may be applied in the X, Y, or Z axis.


 Installation
 ------------
 Barracuda 9LP FC disc drive installation is a plug-and-play process.
 There are no jumpers, switches, or terminators on the drive. Simply
 plug the drive into the host's 40-pin Fibre Channel backpanel
 connector (FC-SCA)- no cables are required.

 Use the FC-AL interface to select drive ID and all option
 configurations for devices on the loop.
 If multiple devices are on the same FC-AL and physical addresses are
 used, set the device selection IDs (SEL IDs) on the backpanel so that
 no two devices have the same selection ID. This is called the hard
 assigned arbitrated loop physical address (AL_PA). There are 125
 AL_PAs available. If you set the AL_PA on the backpanel to any value
 other than 0, the device plugged into the backpanel's SCA connector
 inherits this AL_PA. In the event you don't successfully assign
 unique hard addresses (and therefore have duplicate selection IDs
 assigned to two or more devices), the FC-AL generates a message
 indicating this condition. If you set the AL_PA on the backpanel to
 a value of 0, the system issues a unique soft-assigned physical
 address automatically.

 Loop initialization is the process used to verify or obtain an
 address. The loop initialization process is performed when power is
 applied to the drive, when a device is added or removed from the
 Fibre Channel loop, or when a device times out attempting to win
 arbitration.

 - Set all option selections in the connector prior to applying power
   to the drive. If you change options after applying power to the
   drive, recycle the drive power to activate the new settings.

 - It is not necessary to low-level format this drive. The drive is
   shipped from the factory low-level formatted in 512-byte logical
   blocks. You need to reformat the drive only if you want to select a
   different logical block size.


 Drive orientation
 -----------------
 The drive may be mounted in any orientation. All drive performance
 characterizations, however, have been done with the drive in
 horizontal (discs level) and vertical (drive on its side)
 orientations, which are the two preferred mounting orientations.


 Cooling
 -------
 Cabinet cooling must be designed by the customer so that the ambient
 temperature immediately surrounding the drive will not exceed
 temperature conditions.

 Specific consideration should be given to make sure adequate air
 circulation is present around the printed circuit board assembly
 (PCBA) to meet the requirements.


 Air flow
 --------
 The rack, cabinet, or drawer environment for the drive must provide
 cooling of the electronics and head and disc assembly (HDA). You
 should confirm that adequate cooling is provided using the
 temperature measurement guidelines described below.

 The drive should be oriented, or air flow directed, so that the least
 amount of air-flow resistance is created while providing air flow to
 the electronics and HDA. Also, the shortest possible path between
 the air inlet and exit should be chosen to minimize the travel length
 of air heated by the drive and other heat sources within the
 rack, cabinet, or drawer environment.

 The air-flow patterns are created by one or more fans, either
 forcing or drawing air as shown in the illustrations. Other air-flow
 patterns are acceptable as long as the temperature measurement
 guidelines are met.


 Drive mounting
 --------------
 Mount the drive using the bottom or side mounting holes. If you mount
 the drive using the bottom holes, ensure that you do not physically
 distort the drive by attempting to mount it on a stiff, non-flat
 surface. The allowable mounting surface stiffness is 80 lb/in (14.0
 N/mm). The following equation and paragraph define the allowable
 mounting surface stiffness:

 where K is the mounting surface stiffness
 (units in lb/in or N/mm) and X is the out-of-plane surface distortion
 (units in inches or millimeters). The out-of-plane distortion (X) is
 determined by defining a plane with three of the four mounting points
 fixed and evaluating the out-of-plane deflection of the fourth
 mounting point when a known force (F) is applied to the fourth point.


 Grounding
 ---------
 Signal ground (PCBA) and HDA ground are connected together in the
 drive and cannot be separated by the user. Maximizing the conductive
 contact area between HDA ground and system ground may reduce radiated
 emissions. If you do not want the system chassis to be connected to
 the HDA/PCBA ground, you must provide a nonconductive (electrically
 isolating) method of mounting the drive in the host equipment;
 however, this may increase radiated emissions and is the system
 designer's responsibility.

                 K x X = F < 15lb = 67N


 FC-AL physical interface
 ------------------------
 The operational aspects of Seagate's Fibre Channel drives are
 provided in the Fibre Channel Interface Manual.


 Physical description
 --------------------
 FIbre Channel drives may be connected in a loop together or with
 other compatible FC-AL devices. A maximum of 127 devices may have
 addresses; however, one of the addresses is reserved for a fabric
 port switch device. This means 126 addresses are available for FC-AL
 devices. More FC-AL compatible devices may physically reside on the
 loop, but they will not be functional because they would not be able
 to obtain valid addresses.

 Port bypass circuits (PBCs) allow devices to be inserted into
 unpopulated locations or removed from the loop with loop operation
 recovery after a brief interruption. These PBCs are located external
 to the FC-AL device.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
SEAGATE  ST39173FC  PRODUCT MANUAL 77767522, REV. B

 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.

 Standards
 ---------
 The Barracuda 9LP FC family complies with Seagate standards as noted
 in the appropriate sections of this manual and the Seagate Fibre
 Channel Interface Manual, part number 77767496. The Barracuda 9LP FC
 disc drive is a UL recognized component per UL1950, CSA certified to
 CAN/CSA C22.2 No. 950-95, and VDE certified to VDE 0805 and EN60950.


 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.


 General description
 -------------------
 Barracuda 9LP FC drives are random access storage devices designed to
 support the Fibre Channel Arbitrated Loop (FC-AL) and SCSI Fibre
 Channel Protocol as described in the ANSI specifications, this
 document, and the Fibre Channel Interface Manual (part number
 77767496) which describes the general interface characteristics
 of this drive. ST39173FC drives are classified as intelligent
 peripherals and provide level 2 conformance (highest level) with the
 ANSI SCSI-1 standard.

 You can view the Fibre Channel interface simply as a transport
 vehicle for the supported command set (ST39173FC drives use the SCSI
 command set). In fact, the Fibre Channel interface is unaware
 of the content or meaning of the information being transported. It
 simply packs the SCSI commands in frames, transports them to the
 appropriate devices, and provides error checking to ensure that the
 information reaches its destination accurately.

 The head and disc assembly (HDA) is environmentally sealed at the
 factory. Air recirculates within the HDA through a non-replaceable
 filter to maintain a contamination-free HDA environment.

 The drive contains no parts replaceable by the user and opening the
 HDA for any reason voids your warranty.

 Barracuda 9LP FC 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 heads automatically
 go to the landing zone when power is removed from the drive.

 An automatic shipping lock prevents potential damage to the heads and
 discs that results from  movement during shipping and handling. The
 shipping lock disengages and the head load process begins when
 power is applied to the drive.

 The drives also use a high-performance actuator assembly design that
 provides excellent performance with minimum power dissipation.


 Standard features
 -----------------
 Barracuda 9LP FC drives have the following standard features:
 - Integrated dual port FC-AL controller
 - Concurrent dual port transfers
 - Support for FC arbitrated loop and private loop attachment
 - Differential copper FC drivers and receivers
 - Downloadable firmware using the FC-AL interface
 - Drive selection ID and configuration options are set on the FC-AL
   backpanel or through interface commands.

 Jumpers are not used on the drive.

 - Fibre Channel worldwide name uniquely identifies the drive and each
   port
 - User-selectable logical block size (512 to 4,096 bytes)
 - Selectable frame sizes from 128 to 2,112 bytes
 - Industry standard 3.5-inch low profile (1 inch high) form factor
   dimensions
 - Programmable logical block reallocation scheme
 - Flawed logical block reallocation at format time
 - Programmable auto write and read reallocation
 - Reed-Solomon error correction
 - Sealed head and disc assembly (HDA)
 - No preventive maintenance or adjustments required
 - Dedicated head landing zone
 - Automatic shipping lock
 - Embedded Grey Code track address to eliminate seek errors
 - Self-diagnostics performed at power on
 - 1:1 interleave
 - Zone bit recording (ZBR)
 - Vertical, horizontal, or top down mounting
 - Dynamic spindle brake
 - 1,024 Kbyte data buffer
 - Embedded servo design
 - Supports SCSI enclosure services via interface connector
 - Supports up to 32 initiators
 - Reallocation of defects on command (Port Format)
 - Fibre Channel interface transports SCSI protocol


 Media description
 -----------------
 The media used on the drive has a diameter of approximately 95 mm
 (approximately 3.7 inches). The aluminum substrate is coated with a
 thin film magnetic material, overcoated with a proprietary protective
 layer for improved durability and environmental protection.


 Performance
 -----------
 - 106 Mbytes/sec maximum instantaneous data transfers per port
 - 7,200 RPM spindle; average latency = 4.17 msec
 - Command queuing of up to 128 commands
 - Background processing of queue
 - Supports start and stop commands
 - Adaptive seek velocity; improved seek performance


 Factory-installed accessories
 -----------------------------
 OEM standard drives are shipped with the Barracuda 9LP FC
 Installation Guide (part number 77767523).


 Factory-installed options
 -------------------------
 You may order the following items which are incorporated at the
 manufacturing facility during production or packaged before shipping:
 - 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.


 User-installed accessories
 --------------------------
 The following accessories are available. All kits may be installed in
 the field.

 - Evaluation kit, part number 73473641.
   This kit provides an adapter card ("T-card") to allow cable
   connections for two FC ports and DC power. Two twin axial cables, 6
   feet in length, are included for the input and output connections
   to the FC interface.


 Start/stop time
 ---------------
 If the Motor Start option is disabled, the drive becomes ready within
 25 seconds after DC power is applied. If arecoverable error condition
 is detected during the start sequence, the drive executes a
 recovery procedure and the time to become ready may exceed 25
 seconds. During the start sequence, the drive responds to some
 commands over the FC-AL interface. Stop time is less than 25 seconds
 (maximum) from removal of DC power.

 If the Motor Start option is enabled, the internal controller accepts
 the commands listed in the Fibre Channel Interface Manual less than 3
 seconds after DC power has been applied. After the Motor Start
 command has been received, the drive becomes ready for normal
 operations within 13 seconds (excluding the error recovery
 procedure). The Motor Start command can also be used to command the
 drive to stop the spindle.

 There is no power control switch on the drive.


 Prefetch/multi-segmented cache control
 --------------------------------------
 The drive provides a prefetch/multi-segmented cache algorithm that in
 many cases can enhance system performance. To select this feature the
 host sends the Mode Select command with the proper values in the
 applicable bytes in page 08h. Default is prefetch and read cache
 enabled.

 If the Prefetch feature is enabled, data in contiguous logical blocks
 on the disc immediately beyond that which was requested by a Read
 command are 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). To enable Prefetch, use 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
 segments, 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).


 Cache operation
 ---------------
 Note. Refer to the Fibre Channel Interface Manual for more detail
 concerning the cache bits. Of the 1,024 Kbytes physical buffer space
 in the drive, 967.5 Kbytes can be used as a cache.

 The cache can be divided into logical segments from which data is
 read and to which data is written. The drive keeps track of the
 logical block addresses of the data stored in each segment of the
 cache. If the cache is enabled (see RCD bit in the Fibre Channel
 Interface Manual), data requested by the host with a read
 command is retrieved from the cache, if possible, before any disc
 access is initiated. Data in contiguous logical blocks immediately
 beyond that requested by the Read command can be retrieved and stored
 in the cache for immediate transfer to the initiator on subsequent
 read commands. This is referred to as the prefetch operation.

 Since data that is prefetched may replace data already in the cache
 segment, an initiator can limit the amount of prefetch data to
 optimize system performance. The drive never prefetches more sectors
 than the number specified in bytes 8 and 9 of Mode page 08h. If the
 cache is not enabled, 967.5 Kbytes of the buffer are used as
 a circular buffer for read/writes, with no prefetch operation and no
 segmented cache operation.

 The following is a simplified description of the prefetch/cache
 operation:

 Case A-read command is received and the first logical block is
 already in cache:

 1. Drive transfers to the initiator the first logical block requested
    plus all subsequent contiguous logical blocks that are already in
    the cache. This data may be in multiple segments.

 2. When a requested logical block is reached that is not in any
    segment, the drive fetches it and any remaining requested logical
    block addresses from the disc and puts them in a segment of the
    cache. The drive transfers the remaining requested logical blocks
    from the cache to the initiator in accordance with the
    "buffer-full" ratio specification given in Mode Select
     Disconnect/Reconnect parameters, page 02h.

 3. The drive prefetches additional logical blocks contiguous to those
    transferred in step 2 above and stores them in the segment. The
    drive stops filling the segment when the maximum prefetch value
    has been transferred.

 Case B-read command is received and the first logical block address
 requested is not in any segment of the cache.

 1. The drive fetches the requested logical blocks from the disc and
    transfers them into a segment, and then from there to the
    initiator in accordance with the "buffer-full" ratio specification
    given in Mode Select Dis-connect/Reconnect parameters, page 02h.

 2. The drive prefetches additional logical blocks contiguous to those
    transferred in Case A, step 2 above and stores them in the
    segment. The drive stops filling the segment when the maximum
    prefetch value has been transferred.

    During a prefetch, the drive crosses a cylinder boundary to fetch
    data only if the Discontinuity (DISC) bit is set to 1 in bit 4 of
    byte 2 of the Mode Select parameters page 08h. Default is zero for
    bit 4.

 Each cache segment is actually a self-contained circular buffer whose
 length is an integer number of logical blocks. The wrap-around
 capability of the individual segments greatly enhances the cache's
 overall performance, allowing a wide range of user-selectable
 configurations. The drive supports operation of any integer
 number of segments from 1 to 16. Divide the 967.5 Kbytes in the
 buffer by the number of segments to get the segment size. Default is
 3 segments.

 Note. The size of each segment is not reported by Mode Sense command
 page 08h, bytes 14 and 15. The value 0XFFFF is always reported
 regardless of the actual size of the segment. Sending a size
 specification using the Mode Select command (bytes 14 and 15) does
 not set up a new segment size. 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 an unchangeable parameter.


 Caching write data
 ------------------
 Write caching is a write operation by the drive that makes use of a
 drive buffer storage area where the data to be written to the medium
 is stored while the drive performs the Write command. Write caching
 is enabled independently of read caching. Write caching is enabled by
 default.

 To disable the write cache, use the Write Caching Enable (WCE) bit.

 For write caching, the same buffer space and segmentation is used as
 set up for read functions. When a write command is issued, the cache
 is first checked to see if any logical blocks that are to be written
 are already stored in the cache from a previous read or write
 command. If there are, the respective cache segments are cleared. The
 new data is cached for subsequent read commands. If a 10-byte CDB
 Write command (2Ah) is issued with the data page out (DPO) bit set to
 1, no write data is cached, but the cache segments are still checked
 and cleared, if need be, for any logical blocks that are being
 written.

 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.


 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 imminent drive failure and is designed to provide sufficient
 warning of a failure to allow you to back up the data before an
 actual failure occurs.

 Note. The drive's firmware monitors specific attributes for
 degradation over time but can't predict instantaneous
 Each monitored 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.


 Product warranty
 ----------------
 Beginning on the date of shipment to the customer and continuing for
 a period of five years, Seagate warrants that each product (including
 components and subassemblies) that fails to function properly
 under normal use due to defect in materials or workmanship or due to
 nonconformance to the applicable specifications will be repaired or
 replaced, at Seagate's option and at no charge to the customer, if
 returned by customer at customer's expense to Seagate's designated
 facility in accordance with Seagate's warranty procedure.

 Seagate will pay for transporting the repair or replacement item to
 the customer. For more detailed warranty information, refer to the
 standard terms and conditions of purchase for Seagate products on
 your purchase documentation.

 The remaining warranty for a particular drive can be determined by
 calling Seagate Customer Service at 1-800-468-3472. You can also
 determine remaining warranty using the Seagate web site
 (www.seagate.com).

 The drive serial number is required to determine remaining warranty
 information.


 Defect and error management
 ---------------------------
 The drive, as delivered, complies with this product manual. The read
 error rates and specified storage capacities are not dependent upon
 use of defect management routines by the host (initiator).
 Defect and error management in the SCSI protocol involves the drive
 internal defect/error management and FC-AL system error
 considerations (errors in communications between the initiator and
 the drive). Tools for use in designing a defect/error management plan
 are briefly outlined in this section. References to other sections
 are provided when necessary.


 Drive internal defects/errors
 -----------------------------
 During the initial drive format operation at the factory, media
 defects are identified, tagged as being unusable, and their locations
 recorded on the drive primary defects list (referred to as the "P"
 list and also as the ETF defect list). At factory format time, these
 known defects are also reallocated, that is, reassigned to a new
 place on the medium and the location listed in the defects
 reallocation table. The "P" list is not altered after factory
 formatting. Locations of defects found and reallocated during error
 recovery procedures after drive shipment are listed in the "G" list
 (defects growth list). The "P" and "G" list may be referenced by the
 initiator using the Read Defect Data command.

 Details of the SCSI commands supported by the drive are described in
 the Fibre Channel Interface Manual.

 Also, more information on the drive error recovery philosophy is
 presented in the Fibre Channel Interface Manual.



**********************************************************************
                      G   E   N   E   R   A   L
**********************************************************************
SEAGATE   FC-AL INTERFACE


 An Overview of Fibre Channel
 ---------------------------

 Introduction
 ------------
 Everyone has accepted the fact that we have moved into the Age of
 Information. In this paradigm information itself is a commodity, and
 therefore there is great value in its efficient disbursement.

 Unfortunately, industry has placed greater value in creating
 information, than distributing it. We often hear about new machines
 which are capable of performing prodigious calculation at the blink
 of an eye. New reports of ever faster computers are commonplace.

 Sharing this information, however, has become a priority only
 recently. It seems that although we have moved into the Age of
 Information, one of our biggest challenges is to efficiently
 distribute the information for everyone to use.

 Luckily, a viable solution is at hand. Conceived and supported by
 such industry giants as IBM, Hewlett-Packard, and Sun Microsystems,
 the Fibre Channel is aimed at providing an inexpensive, flexible and
 very high-speed communications system. Most of the popular network
 implementations today can claim to have any two of these elements.
 Since Fibre Channel encompasses all three, it has everything
 necessary to become a resounding success.

 Not the Network
 Fibre Channel has significant advantages over common networks. The
 first difference is speed. The fastest network implementations today
 support transfer data at a little over 100 megabits per second. For
 smaller data files, where a single computer is directly communicating
 with a file server, such speeds are adequate. However, for realtime
 video and sound, or systems where two machines must operate on common
 data even 200 megabits per second is hopelessly inadequate. Fiber
 Channel provides significantly higher rates, from 10 to 250 times
 faster than a typical Local Area Network (LAN). In fact, Fibre
 Channel can transfer data at speeds exceeding 100 megabytes, or 800
 megabits, per second. This speed is sufficient to allow transfer of a
 1024x768 image with 24-bit color at 30 frame per second, and CD-
 quality digital sound.

 This overcomes the bandwidth limitation, which is probably the most
 serious impediment  for LAN performance. As the number of computers
 communicating on a common network increases, the amount of data
 packets increases accordingly.

 This is because data on a LAN is common to all computers on that
 network. The software must decide if a particular message is relevant
 for a particular machine. When several machines are communicating
 with one another, every other machine on the network must contend
 with all of the messages. As the number of messages increases, the
 load for the entire system is increased.

 Fiber channel is a switched system. Much like a telephone system, a
 connection is established between only the parties that need to
 communicate. These parties can share the entire bandwidth of Fibre
 Channel, since they do not have to contend with messages not relevant
 to their communication. LANs attempt to compensate for this by
 increasing the transfer speed, which places an even greater burden on
 the software. Since all protocol for Fibre Channel is handled by
 the hardware, the software overhead is minimal. Fibre Channel also
 supports full parallelism, so if greater capacity is needed, more
 lines can be added. The common analogy for showing the advantages of
 parallelism is the effect of doubling the number of lanes on a
 freeway instead of doubling the speed limit.

 The physical distance between computers is another limiting factor
 for conventional LANs. Ethernet cables usually have a limit of 1000
 feet between machines whereas Fibre Channel can support a link
 between two up to 10 kilometers apart.

 Finally, Fibre Channel is not software intensive. All of the
 essential functions are  handled by hardware, freeing the computer's
 processor to attend to the application at hand. Even the error
 correction for transmitted data is handled by the Fibre Channel
 hardware. In standard LANs this requires precious processor
 resources.


 Advantages for Computing
 ------------------------
 The obvious advantage for Fibre Channel is to facilitate
 communication between machines. Several workstations clustered
 together already surpass the speed and capacity of a VAX, and begin
 to rival the power of a super computer, at a much lower cost. The
 power of concurrent processing is awesome. For example, a single
 neuron inside our brain is much less complex, and operates far slower
 than a common 286 processor. However, millions of neurons working in
 parallel can process information much faster than any processor known
 today. Networking simple logical units, and operating them in
 parallel offers advantages simply unavailable for the fastest single
 processor architectures. These shared architectures require a huge
 amount of communication and data sharing which can only be handled by
 high-speed networks. Fibre Channel not only meets these requirements,
 but meets them inexpensively.

 The hardware industry is partly responsible for the I/O bottleneck.
 By using the processor speed as the primary focus for their sales
 efforts, the bus speeds have languished. With respect to the new
 class of processors, current system bus speeds  are greatly lagging.
 This is something like building a mill which can process 1000 pounds
 of grain a day, and supplying that mill with a single donkey. There
 is little use for a fast processor that spends most of its time
 waiting for data to act upon.  Whether this data comes from disc
 drives, peripherals, or even other processors, today's bus speeds
 would leave most processors idle, and the next generation of
 processors will be many times faster. Fiber Channel provides the
 data transfer capability which can keep current and upcoming
 processors busy.


 Impact on Mass Storage
 ----------------------
 Today's fastest interfaces are capable of transferring data at around
 20 megabytes per second. However, this speed rating is only for
 transferring data. All protocol intercommunication occurs at  much
 slower speeds, resulting in a lower effective data transfer rates,
 typically around 11 megabytes per second. This represents about
 one-tenth of Fibre Channel's current capability. Fibre Channel drives
 do not suffer from device protocols occurring at slower speeds, since
 all communication occurs at 100 megabytes per second, including
 device intercommunication. In addition to this, the drive itself can
 be placed up to 10 kilometers away from the computer. This would have
 two effects on the way mass storage is implemented.

 First, the amount of data a machine could receive would only be
 limited to the transfer speed of the drive. For high performance disc
 arrays this could exceed 50 megabytes per second. Machine and disc
 storage could finally work to provide real-time, full motion video
 and sound for several machines simultaneously. With Fibre Channel's
 ability to work across long distances, these machines could
 conceivably reside many miles apart. For medical applications,
 computer design centers, and real-time networks such as reservations
 systems, this capability would be invaluable.

 Second, such support for transmitting data over large distances would
 allow disc drives to be placed away from the computer itself. This
 would allow for centralized data resource areas within a business
 office, simplifying everything from site planning to maintenance
 procedures. Indeed a centralized data resource center would be
 possible for an entire office complex.

 The development of the Loop will also provide a huge advantage in
 implementing large capacity disc sub systems. The Fast/Wide SCSI
 specification has a theoretical upper limit of 16 total devices
 attached to a single host. The practical maximum is 6 devices. Fibre
 Channel supports a theoretical limit of 256 devices for a common
 host, with a practical implementation of 64 devices. This practical
 limit is a very conservative figure, and implementation with more
 devices are easily possible. The Loop allows system designers to
 build high capacity configurations, well into the terabyte range,
 with much lower overall cost.

 Finally, Fibre Channel is a serial communications device which has
 two immediate advantages. First, the cabling necessary to
 interconnect Fibre Channel devices is very inexpensive when compared
 to SCSI cabling. Fibre Channel cabling is also much easier to
 connect, and replace than SCSI cables, which simplifies the entire
 process of integration and maintenance for a high capacity data
 storage system. For corporations that are currently grappling with a
 the complexity of installation, and high-cost of SCSI cables, this
 feature will prove invaluable for cutting costs and simplifying
 installation and upkeep.

 Secondly, implementing Fibre Channel requires less space on the
 circuit board than SCSI drives. This reduced space requirement would
 allow the drive designers to include extended features which cannot
 currently be implemented. For example, a 3.5-inch form-factor drive
 with Fibre Channel could be designed with  dual-port capability, a
 feature necessary for use with many mainframes and mini-computers.
 The space saved on the circuit board by using Fibre Channel would
 allow for the extra connector and additional circuitry needed for
 dual-port drives.


 Conclusion
 ----------
 The Fibre Channel will provide the corporations with data in much the
 same way the freeway system provided motorists mobility. Access to a
 vast, interconnected information network which is fast, inexpensive,
 and flexible. With the adoption of Fibre Channel as an open ANSI
 standard, its effect on the horizon of computing will be nothing
 short of revolutionary.

 We have become very good at processing data; Fibre Channel allows us
 to move it. The ability to share information will provide the impetus
 for communication, design and development on a scale not previously
 possible. By facilitating the fabled data-highway, Fibre Channel
 will accelerate  to the Age of Information, as the steam engine moved
 us into the Age of Industry.


