
W D E 9 1 0 0 - 0 0 0 8   E N T E R P R    WESTERN DIGITAL
                                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 3.5"/SLIMLINE         Cylinders    6932|     |     |
Capacity form/unform  9105/      MB        Heads          12|     |     |
Seek time   / track   8.0/ 1.0 ms          Sector/track     |     |     |
Controller           SCSI3 SI/WI/ULTR/SC2  Precompensation
Cache/Buffer           512 KB ADAP./SEGMEN Landing Zone
Data transfer rate   10.000 MB/S int       Bytes/Sector      512
                     40.000 MB/S ext SYNC
Recording method     PRML 0/4/4                     operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C         5 55    |    -40 60
Power: sleep              W     Humidity     %        10 90    |      5 95
       standby            W     Altitude    km    -0.300  3.000| -0.300 12.000
       idle           9.2 W     Shock        g        10       |     70
       seek          11.8 W     Rotation   RPM      7200
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit   144BIT REED SOLOMON,SMART
                                MTBF         h    1000000
                                Warranty Month        60
Lift/Lock/Park     YES          Certificates


**********************************************************************
                        L   A   Y   O   U   T
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WESTERN  WDE9100  INSTALLATION GUIDE 4079-001055 REV. B 10/97

  +-LED-----------------------------------------------------+
  |+-+                                                      |XX
  || | Option Block                                         |XXPOWER
  || |                                                      |xx
  || |                                                      |
  || |                                                      |XX1
  |1-+                                                      |XX
  |                                                         |XX
  |                                                         |XX
  |                50-Pin Version                           |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX SCSI
  |                                                         |XX I/O
  |                                                         |XX
  +---------------------------------------------------------+








  +LED------------------------------------------------------+  69
  |+-+                                                      |XX Power
  || | Option Block                                         |XX
  || |                                                      |+-+Remote
  || |                                                      || |Option
  || |                                                      |+-+Block
  |1-+                                                      |XX1
  |                                                         |XX
  |                                                         |XX
  |                68-Pin                                   |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX SCSI
  |                                                         |XX I/O
  |                                                         |XX
  +---------------------------------------------------------+

  +-LED-----------------------------------------------------+
  |+-+                                                      |
  || | Option Block                                         |
  || |                                                      |
  || |                                                      |XX
  || |                                                      |XX
  |1-+                                                      |XX
  |                                                         |XX
  |                                                         |XX
  |                80-Pin                                   |XX
  |                                                         |XX SCSI
  |                                                         |XX I/O
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |
  |                                                         |
  +---------------------------------------------------------+

        -------------------------------------------------
        |                                               |
        |                                               |
        |  +-----/41-------------------------80\-----+  |
        |  |    / ||||||||||||||||||||||||||||| \    |  |
        |  +----+-1---------------------------40+----+  |
        ---------------SCA-2 80-Pin Connector------------



**********************************************************************
                      J   U   M   P   E   R   S
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WESTERN  WDE9100  INSTALLATIN GUIDE 4079-001055 REV. B  10/97

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

 Option Block Functions
 ----------------------
 The firmware uses several pins on the option block to modify the
 drive characteristics. The definitions for the jumpers follow:

 - SCSI ID: Four jumpers are used to identify the default SCSI ID for
   the drive.

 - Disable Auto Start: Use of this jumper disables Auto Start,
   meaning the drive does not spin-up until a START UNIT command is
   issued. Without this jumper, the drive will spin-up and prepare
   itself at power on without having to receive a START UNIT command.

 - Auto Start Delay: Use of this jumper allows the Auto Start to
   incorporate a delay. The delay time equals the SCSI ID multiplied
   by 4 seconds.

 - Disable Target Initiated Synchronous/Wide Negotiation:  Use of this
   jumper dictates that the drive cannot initiate either synchronous
   negotiation or wide negotiation. Without this jumper, the drive
   initiates synchronous and wide negotiation when appropriate.

 - Disable Unit Attention: This controls whether a CHECK CONDITION
   status is reported following a Power On or Reset sequence. A
   REQUEST SENSE command following one of those conditions still
   yields the correct sense data for the UNIT ATTENTION condition, as
   sense data is generated regardless of the jumper setting. A jumper
   on this pin disables the generation of a CHECK CONDITION for the
   Power On and Reset UNIT ATTENTION conditions. With no jumper
   attached, a CHECK CONDITION status is reported in these situations.

 - SCSI Configure Automatically (SCAM): The drive is SCAM levels 1
   and 2 compliant, which eases user configuration of SCSI IDs and
   allows for hot plugging on single and multiple drive systems. Use
   of this jumper allows the drive to function as a SCAM level 2
   device. Without the jumper the drive is not a SCAM device.

 - Active SCSI Termination: To ensure reliable communication, the
   SCSI bus must be properly terminated. Use of this jumper enables
   active termination on the drive. Without this jumper, active
   termination is disabled.


 The option block
 ----------------
 The WD Enterprise drive PCBA contains an option block that controls
 the drive's operation. This block is equipped with jumper pins that
 correspond to various options controlled by SCSI commands. Jumpers
 are used to enable or disable the options and modify the
 drive configuration.

 Note: Whenever you change a jumper setting, it will take effect the
 next time the drive is powered on.


 Option Block Pin Assignments
 ----------------------------
 The option block is used to modify the drive characteristics and
 make connections to external devices.
 +----------------+------+------------------------------------------+
 |OPTION/SIGNAL   |PINS  |CONFIGURATION NOTES                       |
 |SCSI  ID        |01-08 |                                          |
 +----------------+------+------------------------------------------+
 |(KEY)/LED-      | X-10 |X - NO PIN/10 - LED CATHODE CONNECTION    |
 +----------------+------+------------------------------------------+
 |RESERVED        |11-12 |11 - GROUND/12 - LED ANODE CONNECTION     |
 +----------------+------+------------------------------------------+
 |OPT 1: DISABLE  |13-14 |INSTALL JUMPER TO DISABLE AUTO START      |
 |AUTO START      |      |                                          |
 +----------------+------+------------------------------------------+
 |OPT 2: AUTO     |15-16 |INSTALL JUMPER TO ENABLE AUTO START DELAY |
 |START DELAY     |      |                                          |
 +----------------+------+------------------------------------------+
 |OPT 3: SCAM     |17-18 |INSTALL JUMPER TO ENABLE SCAM             |
 +----------------+------+------------------------------------------+
 |OPT 4: DISABLE  |19-20 |INSTALL JUMPER TO DISABLE UNIT ATTENTION  |
 |UNIT ATTENTION  |      |                                          |
 +----------------+------+------------------------------------------+
 |OPT 5: DISABLE  |21-22 |INSTALL JUMPER TO DISABLE TARGET INITIATED|
 |TARGET INITIATED|      |SYNCHRONOUS/WIDE NEGOTATION               |
 |SYNCHRONOUS/WIDE|      |                                          |
 |NEGOTATION      |      |                                          |
 +----------------+------+------------------------------------------+
 |OPT 6: SCSI     |23-24 |INSTALL JUMPER TO ENABLE SCSI TERMINATION |
 |TERMINATION     |      |                                          |
 +----------------+------+------------------------------------------+
 |TXD/RXD         |25-26 |RESERVED                                  |
 +----------------+------+------------------------------------------+
 |TPWR/+5V        |27-28 |INSTALL JUMPER TO ENABLE TERMPWR ON THE   |
 |                |      |SCSI BUS                                  |
 +----------------+------+------------------------------------------+
 |LED+/+5V        |29-30 |29 - LED ANODE CONNECTION / 30 - RESERVED |
 +----------------+------+------------------------------------------+
 |+12R/+12R       |31-32 |RESERVED                                  |
 +----------------+------+------------------------------------------+
 |+12V/+12V       |33-34 |RESERVED                                  |
 +----------------+------+------------------------------------------+
 NOTE
 Pins 1, 3, 5, 7, 11, 13, 15, 17, 19, 21, and 23 are ground.


 SCSI ID Numbers
 ---------------
 Each device on the SCSI bus requires a unique SCSI ID number
 (0 to 7 for 8-bit drives, 0 to 15 for 16-bit drives). Option
 block pin 1 through 8 are used to set the SCSI IDs. The host
 computer's SCSI controller typically uses ID number 7, and the other
 numbers are used for devices such as hard drives. The WD Enterprise
 has a default SCSI ID of 0.


 SCSI ID 8-bit
 -------------
   +----------+-----------------------+
   | SCSI ID  |        Jumpers        |
   |          | 5&6   | 3&4   | 1&2   |
   +----------+-------+-------+-------+
   |x   0     | OPEN  | OPEN  | OPEN  |
   +----------+-------+-------+-------+
   |    1     | OPEN  | OPEN  | CLOSED|
   +----------+-------+-------+-------+
   |    2     | OPEN  | CLOSED| OPEN  |
   +----------+-------+-------+-------+
   |    3     | OPEN  | CLOSED| CLOSED|
   +----------+-------+-------+-------+
   |    4     | CLOSED| OPEN  | OPEN  |
   +----------+-------+-------+-------+
   |    5     | CLOSED| OPEN  | CLOSED|
   +----------+-------+-------+-------+
   |    6     | CLOSED| CLOSED| OPEN  |
   +----------+-------+-------+-------+
   |    7     | CLOSED| CLOSED| CLOSED|
   +----------+-------+-------+-------+

 SCSI ID - 16-bit
 ----------------
   +----------+-------------------------------+  80-Pin
   | SCSI ID  |       Jumper Location         |  Pin 39 SCSI ID 0
   |          |             PINS              |  Pin 40 SCSI ID 2
   |          |  7-8  |  5-6  |  3-4  |  1-2  |  Pin 79 SCSI ID 1
   +----------+-------+-------+-------+-------+  Pin 80 SCSI ID 3
   |    0     | OPEN  | OPEN  | OPEN  | OPEN  |
   +----------+-------+-------+-------+-------+  Pin 01 +12V
   |    1     | OPEN  | OPEN  | OPEN  | CLOSED|      02 +12V
   +----------+-------+-------+-------+-------+      03 +12V
   |    2     | OPEN  | OPEN  | CLOSED| OPEN  |      04 +12V
   +----------+-------+-------+-------+-------+      41 +12V GND
   |    3     | OPEN  | OPEN  | CLOSED| CLOSED|      42 +12V GND
   +----------+-------+-------+-------+-------+      43 +12V GND
   |    4     | OPEN  | CLOSED| OPEN  | OPEN  |      44 MATED1
   +----------+-------+-------+-------+-------+      34-36 +5V
   |    5     | OPEN  | CLOSED| OPEN  | CLOSED|      74 GND
   +----------+-------+-------+-------+-------+      75 +5V GND
   |    6     | OPEN  | CLOSED| CLOSED| OPEN  |      76 +5V GND
   +----------+-------+-------+-------+-------+
   |    7     | OPEN  | CLOSED| CLOSED| CLOSED|
   +----------+-------+-------+-------+-------+
   |    8     | CLOSED| OPEN  | OPEN  | OPEN  |
   +----------+-------+-------+-------+-------+
   |    9     | CLOSED| OPEN  | OPEN  | CLOSED|
   +----------+-------+-------+-------+-------+
   |   10     | CLOSED| OPEN  | CLOSED| OPEN  |
   +----------+-------+-------+-------+-------+
   |   11     | CLOSED| OPEN  | CLOSED| CLOSED|
   +----------+-------+-------+-------+-------+
   |   12     | CLOSED| CLOSED| OPEN  | OPEN  |
   +----------+-------+-------+-------+-------+
   |   13     | CLOSED| CLOSED| OPEN  | CLOSED|
   +----------+-------+-------+-------+-------+
   |   14     | CLOSED| CLOSED| CLOSED| OPEN  |
   +----------+-------+-------+-------+-------+
   |   15     | CLOSED| CLOSED| CLOSED| CLOSED|
   +----------+-------+-------+-------+-------+


 Remote Option for 68-Pin Connector
 ----------------------------------
 Signal Name   | SFF-8009   | SFF-8009  | Pin Number
               | Signal Name| Pin Number|
 --------------+------------+-----------+-----------
 SCSI  ID 0    | SEL0-      |     1     |     69
 --------------+------------+-----------+-----------
 SCSI  ID 1    | SEL1-      |     3     |     71
 --------------+------------+-----------+-----------
 SCSI  ID 2    | SEL2-      |     5     |     73
 --------------+------------+-----------+-----------
 SCSI  ID 3    | SEL3-      |     7     |     75
 --------------+------------+-----------+-----------
 TERMEN-       | ENTERM-    |     9     |     77
 --------------+------------+-----------+-----------
 +5V           | +5V        |    11     |     79
 --------------+------------+-----------+-----------
               |            |           |
 --------------+------------+-----------+-----------
 GND/OPEN      | XTFALT-    |     2     |     70
 --------------+------------+-----------+-----------
 GROUND        | VUNIQ-     |     4     |     72
 --------------+------------+-----------+-----------
 GND/OPEN      | GND/OPEN   |     6     |     74
 --------------+------------+-----------+-----------
 LED-          | XTACTV-    |     8     |     10
 --------------+------------+-----------+-----------
 GROUND        | GROUND     |    10     |     78
 --------------+------------+-----------+-----------
 NO CONNECTION | FAULT-     |    12     |     80



**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
WESTERN  WDE9100  INSTALLATION GUIDE 4079-001055 REV. B  10/97

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

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

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

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

 Mounting
 --------
 The WDE9100 features side and bottom mounting holes, which allow the
 drive to be mounted in any orientation.

 The hard drive is a precision mechanical assembly. Improper mounting
 may distort the drive frame and/or amplify shock and vibration inputs
 resulting in degraded drive performance. For instructions on
 installing the drive, including drive handling and mounting, refer to
 the WD Enterprise Installation Guide (document number 4079-001057).


 Operating Shock
 ---------------
 WD Enterprise drives are tested by applying a linear shock in each
 axis, one axis at a time, at a rate not exceeding two shocks per
 second.


 Non-operating Shock
 -------------------
 WD Enterprise drives are tested by applying a linear shock in each
 axis, one axis at a time. A maximum of three shocks per axis is
 applied.


 Non-operating Rotational Shock
 ------------------------------
 WD Enterprise drives are tested by applying a rotational shock in
 each direction, about each axis, one axis at a time.


 Operating Vibration
 -------------------
 WD Enterprise drives are tested by applying a continuous swept sine
 excitation in each linear axis, one axis at a time. Sweep rate is
 0.25 octave per minute.


 Non-operating Vibration
 -----------------------
 Note: This specification applies to handling and transportation of
 unmounted drives.

 Drives are tested by applying a continuous swept sine excitation in
 each linear axis, one axis at a time. Sweep rate is one octave per
 minute.


 Packaged Shock and Vibration
 ----------------------------
 The shipping packaging is designed to meet the National/International
 Safe Transit Association (N/ISTA) standards for packaged products.
 The drive incurs no physical damage when subjected to the N/ISTA
 standards.


 Cooling
 -------
 Sustained operation at temperatures in excess of the reliability
 values degrades the MTBF rating. Short excursions up to, but not
 exceeding, the maximum values will not affect the MTBF rating.
 Maximum component temperature ratings must not be exceeded under any
 operating condition. The drive may require forced air cooling to meet
 specified operating temperatures.


 Read Caching and Pre-Fetch
 --------------------------
 Read caching allows the drive to maintain data in the cache for quick
 transfer to the host when a media access is not required.
 Pre-fetching takes place after a media access when the drive reads
 data into the cache that the firmware determines is likely to be
 requested by the host. Refer to the Western Digital SCSI
 Implementation Guide (document number 4096-001343) for further
 details.


 Write Caching
 -------------
 Write caching gives the host the ability to allow the drive to
 asynchronously write data to the media while other processes occur.
 Refer to the Western Digital SCSI Implementation Guide (document
 number 4096-001343) for further details.


 Write Coalescing
 ----------------
 Write coalescing allows the drive to combine write commands that
 write data to sequential portions of the media into one operation.
 This feature improves performance by reducing the number of
 revolutions needed to write data to the media. Refer to the Western
 Digital SCSI Implementation Guide (document number 4096-001343) for
 further details.


 Serpentine Seek Technology
 --------------------------
 Western Digital's Serpentine seek technology effectively reduces the
 overhead associated with actuator movement, thereby increasing
 sustained data throughput. Serpentine seek technology alters the
 traditional hard drive format to create a "winding" track-to-track
 pattern. This unique pattern emphasizes short, quick actuator
 movements that occur in a predictable fashion. This enhances the
 drive's ability to keep data streaming on and off the media with
 minimal disruption.


 512 Kilobyte Data Buffer
 ------------------------
 The entire data buffer is user accessible, enabling powerful data
 caching capabilities.


 Adaptive Caching
 ----------------
 The WDE9100 is equipped with an adaptive caching capability which
 enables the drive to improve performance and throughput based on how
 the drive is being used. Each drive determines the environment in
 which it is being used and optimizes the way it handles commands and
 data.


 Command Queuing and Reordering
 ------------------------------
 The WDE9100 supports both tagged and untagged queuing. Tagged queuing
 allows the drive to receive multiple I/O processes from each
 initiator. Untagged queuing allows the drive to receive a maximum of
 one I/O process from each initiator.

 In order to use tagged command queuing, the initiator must set the
 disconnect privilege bit. This allows the drive to disconnect from
 the SCSI bus. It also allows the same or other initiators to connect
 to the drive and send additional commands. The drive returns a status
 of BUSY if the disconnect privilege bit is off and the drive has I/O
 processes in the command queue. The drive has the capability to queue
 up to 64 I/O processes. Upon receipt of the 65th I/O process, the
 drive returns a status of QUEUE FULL.

 The drive can reorder I/O processes in the command queue. The order
 in which the drive executes I/O processes may differ from the order
 in which they were received.

 Command reordering employs an algorithm which improves the throughput
 of the drive by attempting to minimize both the seek time and the
 rotational latency.

 The drive uses a command aging feature to prevent the command
 reordering algorithm from keeping I/O processes waiting in the
 command queue for extended periods of time. The drive allows I/O
 processes to wait in the command queue for only a specified length of
 time before they are scheduled in the next I/O process.


 LED Support
 -----------
 An LED is installed on the drive:
 The LED is turned off as soon as power is applied. If Auto Start is
 enabled, the LED is on while the drive is spinning up and turned off
 when Auto Start is completed.

 The LED is on when a SCSI command is being executed.

 The LED flashes when an error prohibits the use of the SCSI
 interface.


 Hot Plug/Unplug Support
 -----------------------
 The conditions for hot-plugging drives into an active SCSI bus
 follow:

 - The drive signal ground must be made before the SCSI bus signals.

 - Power-both +5V and +12V-cannot be applied until the SCSI bus
   signals are connected.

 - The host(s) are not actively trying to access the inserted device.

 - The drive is not supplying TERMPWR to the SCSI bus.

 - The drive is not supplying termination to the SCSI bus.

 The conditions for the removal of a device from an active SCSI bus
 follow:

 - The host(s) are not actively trying to access the device to be
   removed.

 - The drive is not supplying TERMPWR to the SCSI bus.

 - The drive is not supplying termination to the SCSI bus.

 - Power-both +5V and +12V-must be removed before the SCSI bus signals
   are disconnected.

 - The drive signal ground must be broken after the SCSI bus signals.

 The SCA-2 (80-pin) connector allows for proper insertion and
 extraction by providing an appropriate mechanical mating that makes
 the signal ground connection first upon insertion and last upon
 extraction. There are also control signals that allow the proper
 application of power to adhere to the insertion and extraction rules
 above. However, the user must guarantee that the three rules listed
 below apply:

 The host(s) are not actively trying to access the inserted device.

 The drive is not supplying TERMPWR to the SCSI bus.

 The drive is not supplying termination to the SCSI bus.


 Physical Characteristics (Option Block)
 ---------------------------------------
 The block consists of a 2-pin by 17-pin male header. Pin-to-pin
 spacing is 2 mm by 2 mm.


 SCSI Connectors
 ---------------
 Power Connectors and Cables
 50-pin Drive Power Connector and Cable
 POWER CONNECTOR   MATING CONNECTOR         WIRE GAUGE
 AMP 2-in-1        1x4 PC power connector   18 AWG

 68-pin Drive Power Connector and Cable
 POWER CONNECTOR                    MATING CONNECTOR       WIRE GAUGE
 Molex 3-in-1 combo (or equivalent) 1x4 PC power connector 18 AWG


 SCSI Physical Interface
 -----------------------
 All Western Digital SCSI hard drives are designed to conform to the
 SCSI-3 Parallel Interface as described in the draft of proposed ANSI
 specification X3T10/855D Revision 15a. In addition, drives equipped
 with the 80-pin SCA connector are designed to conform to the Small
 Form Factor Committee draft specification SFF-8046 Rev 2.0 entitled
 "SCA-2 (Single Connector Attach) for SCSI Disk Drives." Since
 tutorials on SCSI-3 and SCA are beyond the scope of this manual,
 users should review their SCSI implementations as required to ensure
 compliance. The SCSI-3 specification has several informative annex
 sections on cabling, bus termination, crosstalk, etc., that are quite
 helpful to SCSI system architects and implementors.


 DC Power Connector
 ------------------
 Signal Name         Pin Number    Signal Name
 +12V (+12 SUPPLY)   51  52        GROUND (+12 RETURN)
 GROUND (+5 RETURN)  53  54        +5V (+5 SUPPLY)


 Installation and Maintenance
 ----------------------------
 For instructions on installing the drive, including drive handling
 and mounting, determining the configuration, setting the drive
 jumpers, and cabling procedures, refer to the WD Enterprise
 Installation Guide (document number 4079-001057).


 Electrostatic Discharge (ESD) Protection
 ----------------------------------------
 To prevent drive damage, it is essential to keep the drive in an ESD
 safe environment. You can take several precautions to avoid permanent
 damage to the drive.

 - Keep the drive in the shielded anti-static bag prior to testing or
   installation.

 - Gently place the drive on a padded, grounded anti-static surface
   when it is not in its shipping container.

 - Wear a grounded wrist strap throughout all phases of drive
   handling.

 - Do not allow clothing to come in direct contact with the drive or
   PCBA.

 - Do not insert any other items in the shielded anti-static bag with
   the drive.


 External Air Filter
 -------------------
 In addition, adequate clearance above this region must be maintained
 to allow the free exchange of air. This region contains the external
 air filter, which allows the pressure inside the drive to equalize
 with the ambient atmosphere. If obstructed, the filter may not be
 able to compensate for expansion and contraction of the air inside
 the drive, which may degrade drive performance.


 Maintaining the Drive
 ---------------------
 To keep the drive in optimal working order and prolong the life of
 the unit, do the following:

 - Do not attempt to open the sealed compartment of the WDE9100 drive;
   this will void the warranty.

 - Avoid harsh shocks or vibrations.

 - Observe the environmental limits specified for this product.

 - To protect your data, back it up regularly. Western Digital assumes
   no responsibility for loss of data. For information about back-up
   and restore procedures, consult your operating system manual. There
   are a number of utility programs to back up your data.

 Caution: Do not remove any product identification labels.
 The drive requires no preventive maintenance and contains no
 user-serviceable parts. Service and repair of the drive must be
 performed at a Western Digital Service Center. Contact your Western
 Digital representative for warranty information and service/return
 procedures.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
WESTERN  WDE9100  INSTALLATION GUIDE 4079-001055 REV. B  10/97

 General Description
 -------------------
 Western Digital, the recognized leader in time to volume hard drive
 manufacturing, is first to offer a low-profile 9.1 GB high-
 performance SCSI hard drive. Our team of expert enterprise
 storage engineers developed this leading-edge drive using Western
 Digital's proven technology and world-class quality processes.

 The WD Enterprise WDE9100 - the second in a family of low-profile
 7200 RPM drives - delivers outstanding performance, capacity, and
 reliability, and is an excellent choice for workstation, server,
 multi-user, data warehousing, audio-video, and array/RAID
 applications.

 The drive features a formatted capacity of 9.1 GB in a low-profile
 form factor with Ultra SCSI host data transfer rates up to 40 MB/s.
 This device also supports high performance I/O features such as
 adaptive caching, command queuing, command reordering, active
 termination, S.M.A.R.T. (Self Monitoring, Analysis, and Reporting
 Technology), and SCAM (SCSI Configure AutoMagically) that allow for
 multi-threaded I/O and more intelligent drive reporting. This drive
 supports 50-pin, 68-pin, and 80-pin (SCA-2) connectors. In addition,
 advanced data protection capabilities such as thermal asperity
 detection and correction in hardware make this hard drive ideal for
 the mission critical enterprise computing environment.

 The WD Enterprise WDE9100 delivers the performance, capacity, and
 reliability demanded by all high-performance enterprise systems.


 Advanced Features
 -----------------
 Product Features
 - Formatted Capacity of 9.1 GB

 - 3.5-Inch Low Profile (1-inch high)

 - Magnetoresistive Heads

 - 7200 RPM Spindle Speed

 - SCSI-3 SPI Compliant; Ultra Fast/Ultra Fast Wide with SCA-2
   interface supported

 - 512 kilobytes Programmable Multi-segmented Data Buffer (1 MB
   option)

 - Zoned Recording

 - Headerless Format

 - SCAM Plug-N-Play Compliant

 - Single-ended SCSI Drivers/Receivers

 - Active Termination (available on 50- and 68-pin single-ended
   drives)

 - Downloadable SCSI and Servo Firmware

 - Ultra SCSI Interface Supported for up to 40 MB/s Host Transfer
   Rates

 - Embedded Servo

 - Balanced Spindle

 - Dynamic Spindle Brake

 - Vertical or Horizontal Mounting


 Performance Features
 --------------------
 - Serpentine Seek Technology

 - Media Data Rate Up to 160 Mbits/s (20MB/s)

 - Average Read Seek Time of < 8 ms

 - 4.17 ms Rotational Latency

 - Tagged Command Queuing

 - Seek and Rotational Command Reordering

 - Write/Read Coalescing

 - Adaptive Caching

 - Self-Optimizing Buffer Ratios

 - Adaptive Segmented Cache

 - Auto-Read Reallocation/Auto-Write Reallocation (ARRE/AWRE)

 - Adaptive Servo Functions

 NOTE 50-pin and 68-pin drives can be ordered with or without
      terminators.


 Reliability Features
 --------------------
 - Self Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.)

 - Thermal Asperity Detection and Correction in Hardware

 - E-coat Base Casting

 - Hardware On-The-Fly Error Correction

 - CRC Data Buffer Protection

 - Sector Slipping Defect Management

 - Self Diagnostics on Power Up

 - 1,000,000 Hour MTBF POH


 Options
 -------
 The following options are incorporated at the time of production, or
 shipped separately upon request.

 - Data buffer of 1 megabyte
   The standard data buffer size is 512 kilobytes. You may order a 1
   megabyte option.

 - Single-unit shipping pack kit
   The drive is shipped in bulk packaging to provide maximum
   protection against damage during transit. Units shipped
   individually require additional protection as provided by the
   single-unit shipping pack. Contact your local Western Digital
   sales office for ordering information.


 Termination Power
 -----------------
 50-pin and 68-pin drives have the ability to supply termination power
 to the SCSI bus. This option can be enabled by setting the
 corresponding jumper on the option block.


 Bring-Up Sequence
 -----------------
 After power is applied, the following events occur as the drive
 becomes ready for use.

 1. The microprocessor tests itself, the on-board memory, and
    components on the printed circuit board assembly (PCBA).

 2. The SCSI interface is enabled to accept the following commands:
    Inquiry, Request Sense, Start/Stop Unit, Test Unit Ready. Refer to
    the Western Digital SCSI Implementation Guide (document number
    4096-001343) for additional SCSI commands and features.

 3. Internal electronic component initialization and testing
    continues.

 4. If the Auto Start option is enabled, the motor spins up.

 5. The servo system calibrates itself.

 6. Additional configuration information is read from an area on the
    disk that is reserved for the drive's internal use.

 7. A self test is performed on the read/write path.

 8. The drive is ready to read and write data.

 If an error occurs during the bring-up sequence, sense data is
 available if the SCSI interface is working; otherwise the LED
 flashes.

 If a reassign was in progress when the drive was turned off, the
 drive automatically completes that operation during startup.


 Regulatory Agency Information
 -----------------------------
 The drive has met the following regulatory agency standards:

 Underwriters Laboratories
 UL-Standard 1950, Standard for Safety of Information Technology
 Equipment including Electrical Business Equipment
 File Number E101559

 Federal Communication Commission
 Verified to comply with FCC Rules for Radiated and Conducted
 Emission, Part 15, Subpart B, for Class B Equipment

 Canadian Standards Association
 CSA-Standard C22.2, No. 950 - M89, Standard for Safety of Information
 Technology Equipment including Electrical Business Equipment
 File Number LR 68850

 TUV Essen Laboratories
 IEC 950 (EN 60 950) Standard for Safety of Information Technology
 Equipment including Electrical Business Equipment

 CE Compliance for Europe
 Verified to comply with EN 55022 for RF Emissions and EN 50082-1 for
 Generic Immunity as applicable.


 Advanced product features
 -------------------------
 Compatibility Testing
 Western Digital performs extensive testing in its Functional
 Integrity Test Lab (FIT Lab). By equipping the FIT Lab with
 multiple host systems, adapters, operating systems, and application
 programs, compatibility is achieved with a broad range of
 applications implemented on workstations, servers, multi-user, and
 array systems.


 SCSI-3 SPI Compliant
 --------------------
 The WDE9100 conforms to the SCSI-3 SPI (SCSI Parallel Interface)
 standard. The drive also supports the Ultra SCSI performance
 specification and is offered in several configurations such as Ultra
 Fast (8-bit, 50-pin; up to 20MB/s) and Ultra Fast Wide (16-bit,
 68-pin, 80-pin SCA-2; up to 40MB/s) host transfer rates.


 Embedded Servo Control
 ----------------------
 The WDE9100 features embedded servo technology to generate accurate
 positioning information on every track. An embedded servo system has
 servo bursts interspersed with customer data on every track. This
 provides a tight coupling between head positioning and user data. In
 addition, embedded servo technology is less susceptible to thermal
 shifts of the system since customer data and position information are
 recorded together on the same track.


 Media Defect Management
 -----------------------
 Western Digital drives support a defect management algorithm that
 uses sector slipping. Defective sites are pushed down during a
 reassignment operation to maintain a sequential order. Spare sectors
 are placed throughout the drive to support this algorithm. This
 routine can be invoked by the drive when Auto-Read Reallocation/
 Auto-Write Reallocation (ARRE/AWRE) is enabled in MODE SELECT Page 1.
 If ARRE/AWRE functions are disabled, the drive reports the status and
 may recommend the host request a reassign.


 Microcode Download
 ------------------
 Western Digital drives support downloadable microcode via the SCSI
 WRITE BUFFER command. The supported modes include Download Microcode
 and Save, as well as Download Microcode with Offsets and Save.

 Download Microcode with Offsets is used when the buffer is limited to
 the full download and requires smaller partial downloads to complete
 the download task.


 Reed Solomon ECC On-the-Fly
 ---------------------------
 Error Correction Code (ECC) on-the-fly is a correction technique that
 reduces the uncorrectable read error rate in hardware. This provides
 a high degree of data integrity with no impact on the drive's
 performance.


 CRC Data Protection
 -------------------
 Cyclic Redundancy Check (CRC) data protection is a feature that
 enhances data integrity. The WDE9100 uses CRC protection for both the
 data buffer path and also for protection against ECC miscorrection.
 During a write operation, before a user data block enters the cache
 (data buffer), the SCSI controller generates CRC data (2 bytes) and
 attaches it to the user data block (usually 512 bytes). In addition,
 prior to generating the data ECC bytes, four CRC bytes are then added
 to the existing bytes (data bytes and 2 CRC bytes).

 During a read operation, after the drive has done its ECC check and
 possible correction, the four byte CRC operation takes place. In the
 unlikely event a miscorrection results from the ECC operation, the
 CRC detects this and the read is repeated. If the CRC check is
 successful, the data is put in the drive cache. The two byte CRC
 check occurs when the data is being transferred out of the SCSI
 controller chip to the host controller. A CRC error at this juncture
 results in a check condition to inform the host controller of the
 error.


 Zoned Recording
 ---------------
 The WDE9100 employs zoned recording to increase data density on the
 outer tracks of the drive. Zoned recording allows the adjustment of
 the number of sectors per track, which provides storage of more
 sectors on the larger, outer tracks. Formatting packs data uniformly
 throughout the surface of the platter by dividing the outer tracks
 into more sectors. With more bytes per track, the drive reads the
 data in the outer zones at a faster rate.


 Headerless Format
 -----------------
 Headerless format is also known as ID-less or No-ID sector format.
 This format removes the header (or ID fields) and all the information
 within the header (track format) to provide a dramatic increase in
 user capacity. Our advanced, integrated SCSI controller assumes the
 task of determining the physical location of each sector.


 Auto-Read Reallocation/Auto-Write Reallocation (ARRE/AWRE)
 ----------------------------------------------------------
 This error recovery feature controls whether automatic reallocation
 takes place during read and write commands. If enabled, the drive may
 perform automatic reallocations to correct a potentially defective
 sector.


 Magnetoresistive (MR) Heads
 ---------------------------
 The WDE9100 incorporates magnetoresistive heads to meet increasing
 capacity requirements. The MR head uses separate read and write
 elements in order to optimize read and write capabilities. The write
 element is a thin-film inductive element that records data. The read
 element, composed of a thin-film material whose resistance changes in
 the presence of a magnetic field, produces a strong signal, allowing
 significant increases in areal densities. When MR heads are used in
 combination with a PRML read channel, capacities can be significantly
 increased.


 Thermal Asperity (TA) Detection and Correction
 ----------------------------------------------
 A thermal asperity (media defect or particulate) can cause a sudden
 transfer of energy to an MR head, and the resistance change that
 accompanies this activity can limit the drive's ability to read and
 write for a period of time. The WDE9100 uses advanced techniques to
 detect an increased thermal condition due to an asperity. If a data
 error occurs, several recovery algorithms are used to recover the
 data in read or write modes.


 E-coat Base Casting
 -------------------
 The WDE9100 base casting has an electro-deposited organic coating,
 commonly referred to as E-coat. This smooth coating reduces the
 particle count inside the drive housing, which results in a clean
 environment for MR heads.


 Error Recovery Operations
 -------------------------
 Error recovery options are set using MODE SELECT Page 1 (Read/Write
 Error Recovery Page) and the Write Recovery Threshold and Read
 Recovery Threshold fields in MODE SELECT Page 0 (WD Vendor Unique
 Page).

 The drive employs a variety of recovery actions based on the type of
 error that occurs. Separate recovery actions are defined for read
 errors, write errors, servo errors, and drive fault errors. For a
 given error type, several different recovery actions may be used. For
 example, read error recovery may use retries, servo track offsets,
 channel parameter modification, and software ECC in an attempt to
 recover the error. Error information is available to the host via the
 REQUEST SENSE command based on the settings in MODE SELECT Pages 0
 and 1.

 The drive uses a 3-way interleaved Reed-Solomon ECC operating on 8
 bit (1 byte) symbols. On-the-fly ECC is capable of correcting single
 burst errors up to 1 byte per interleave (3 bytes total) with no
 performance degradation. On-the-fly correction is done in hardware
 and cannot be disabled. The drive firmware also implements a software
 ECC, which is capable of correcting random errors up to 3 bytes per
 interleave (9 bytes total) and burst errors up to 5 bytes per
 interleave (15 bytes total). Refer to the Western Digital SCSI
 Implementation Guide (document number 4096-001343) for more
 information.


 Self-Monitoring, Analysis, and Reporting Technology (S.M.A.R.T.)
 ----------------------------------------------------------------
 Self-Monitoring, Analysis and Reporting Technology (S.M.A.R.T.) is a
 hard drive firmware technology that performs drive failure prediction
 by monitoring selected parameters during normal drive operations. The
 intent of this technology is to minimize unscheduled system downtime
 caused by predictable failures. By monitoring selected parameters,
 the S.M.A.R.T. firmware can predict some drive failures before they
 actually occur, allowing the user to schedule drive replacement and
 minimize system interruptions.


