S W I F T   9 4 3 3 5 - 1 5 0    IMPRIMIS
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 3.5"/HH               Cylinders    1072|     |     |
Capacity form/unform   128/  151 MB        Heads           9|     |     |
Seek time   / track  14.5/ 4.0 ms          Sector/track   26|     |     |
Controller           RLL / ST412           Precompensation   300
Cache/Buffer               KB              Landing Zone
Data transfer rate    0.938 MB/S int       Bytes/Sector      512
                            MB/S ext
Recording method     RLL                            operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C        10 50    |    -40 70
Power: sleep              W     Humidity     %         8 80    |      5 95
       standby            W     Altitude    km    -0.305  3.048| -0.305 12.210
       idle           8.0 W     Shock        g         2       |     50
       seek          10.0 W     Rotation   RPM      3600
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit
                                MTBF         h      30000
                                Warranty Month
Lift/Lock/Park     YES          Certificates     CSA,FCC,IEC380,IEC435,UL47...

**********************************************************************
                        L   A   Y   O   U   T
**********************************************************************
SEAGATE  ST1100/ST1150R  PRODUCT MANUAL 36136-001, REV. B

  +---------------------------------------------------------+
  |                                         J7 +--------+1  |X1
  |                                            +--------+   |XX
  |                                                     ++  |XXControl
  |                                          Terminator ||  |XXCable
  |                                          Resistor   ||  |XX
  |                                          Sip        ||  |XX
  |                                                     ++  |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |
  |                                                         |X1
  |                                                         |XX
  |                                                         |XXData
  |                                                         |XXCable
  |                                                         |XX
  |                                                         |XX
  +---------------------------------------------------------+



**********************************************************************
                      J   U   M   P   E   R   S
**********************************************************************
SEAGATE  ST1100/ST1150R  PRODUCT MANUAL 36136-001, REV. B

 Jumper setting
 ==============

 x = Jumpers set at factory


 J3  Power Connector
 -------------------
     +---+
     | 1 +------- 12 V
     | 2 +------- 12 V Return
     | 3 +-------  5 V Return
     | 4 +-------  5 V
     +---+



 J4  ST 506 Interface
 --------------------
                  Signal Direction    Signal Direction
   +-----------+                                      +-------------+
   |           |                                      |Signal Ground|
   |           | Terminated                           |No.    No.   |
   |           +------------------------------------->|  2     1    |
   |           | Head Select 2(3)                     |             |
   |           +------------------------------------->|  4     3    |
   |           | Write Gate                           |             |
   |           +------------------------------------->|  6     5    |
   |           | Seek Complete                        |             |
   |           |<-------------------------------------+  8     7    |
   |Controller/| Track 0                              |             |
   |Host       |<-------------------------------------+ 10     9    |
   |Interface  | Write Fault                          |             |
   |           |<-------------------------------------+ 12    11    |
   |           | Head Select 2(0)                     |             |
   |           +------------------------------------->| 14    13    |
   |           | Reserved  to J5 pin 7                |             |
   |           +--------------------------------------+ 16    15    |
   |           | Head Select 2(1)                     |             |
   |           +------------------------------------->| 18    17    |
   |           | Index                                |             |
   |           |<-------------------------------------+ 20    19    |
   |           | Ready                                |             |
   |           |<-------------------------------------+ 22    21    |
   |           | Step                                 |             |
   |           +------------------------------------->| 24    23    |
   |           | Drive Select 1                       |             |
   |           +------------------------------------->| 26    25    |
   |           | Drive Select 2                       |             |
   |           +------------------------------------->| 28    27    |
   |           | Drive Select 3                       |             |
   |           +------------------------------------->| 30    29    |
   |           | Drive Select 4                       |             |
   |           +------------------------------------->| 32    31    |
   |           | Direction In                         |             |
   |           +------------------------------------->| 34    33    |
   |           |                                      |             |
   +-----------+                                      +-------------+
                                                       SWIFT Control
                                                       Cable Connector
                                                       J4
   All signals in the control cable are single ended signals.

 Pin 2 in the command cable (Head Select 2(3)) is defined as Reduced
 Write Current in the Seagate St412 interface. The  SWIFT controls
 write current internally, and thus the line is not needed for this
 function and is used for head selection.



 J5   ST 506 Interface
 ---------------------
                  Signal Direction    Signal Direction
   +-----------+                                      +-------------+
   |           |                                      |Pin No. Type*|
   |           | Drive Selected                       |             |
   |           |<-------------------------------------+  1      SE  |
   |           | Ground                               |             |
   |           +--------------------------------------+  2          |
   |           | Reserved                             |             |
   |           +--------------------------------------+  3      SE  |
   |           | Ground                               |             |
   |           +--------------------------------------+  4          |
   |Controller/| Motor On (Optional)                  |             |
   |Host       +--------------------------------------+  5      SE  |
   |Interface  | Ground                               |             |
   |           +--------------------------------------+  6          |
   |           | Reserved  to J4 Pin 16               |             |
   |           +--------------------------------------+  7      SE  |
   |           | Ground                               |             |
   |           +--------------------------------------+  8          |
   |           | Reserved                             |             |
   |           +--------------------------------------+  9          |
   |           | Reserved                             |             |
   |           +--------------------------------------+ 10          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 11          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 12          |
   |           | +MFM (RLL) Write Data                |             |
   |           +------------------------------------->| 13      DIFF|
   |           | -MFM (RLL) Write Data                |             |
   |           +------------------------------------->| 14      DIFF|
   |           | Ground                               |             |
   |           +--------------------------------------+ 15          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 16          |
   |           | +MFM (RLL) Read Data                 |             |
   |           |<-------------------------------------+ 17      DIFF|
   |           | -MFM (RLL) Read Data                 |             |
   |           |<-------------------------------------+ 18      DIFF|
   |           | Ground                               |             |
   |           +--------------------------------------+ 19          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 20          |
   |           |                                      |             |
   +-----------+                                      +-------------+
                                                       SWIFT Data
                                                       Cable Connector
                                                       J5

 * SE   = Single ended signals
   DIFF = Differential signal


 J7   Drive Select/Radial Select/External Spindle Clock
 ------------------------------------------------------

     +-------------------+
     | 1  3  5  7  9  11 |
     | 2  4  6  8 10  12 |
     +-+--+--+--+--+--+--+
       |  |  |  |  |  +------------ External Spindle Clock Connector
       |  |  |  |  +--------------- Radial Select
       |  |  |  +------------------ Drive Select 4
       |  |  +--------------------- Drive Select 3
       |  +------------------------ Drive Select 2
       +--------------------------- Drive Select 1


 J7  Drive Select
 ----------------

  +----------------------------------------------------+
  |   SELECT            1-2     3-4     5-6     7-8    |
  +----------------------------------------------------+
  |Drive Select 1       CLOSED  OPEN    OPEN    OPEN   |
  |Drive Select 2       OPEN    CLOSED  OPEN    OPEN   |
  |Drive Select 3       OPEN    OPEN    CLOSED  OPEN   |
  |Drive Select 4       OPEN    OPEN    OPEN    CLOSED |
  +----------------------------------------------------+


 Drive Select 1-2-3-4
 --------------------
 These lines are used to activate a device's drivers and receivers
 for up to four drives in a daisychained operation.
 The following characteristics apply to the DRIVE SELECT lines:

  1.   Logical unit designation is accomplished at the time of
       installation by setting the jumper plug located on the printed
       Circuit board.

  2.   All command cable lines are gated with DRIVE SELECT. No data
       cable signal lines are gated with DRIVE SELECT.

  3.   DRIVE SELECT must remain asserted during any communication with
       the host controller.

  4.   When the radial select jumper is installed, the drive is
       selected all the time.

  5.   The drive should not be selected until 1 second after DC power
       is applied. The Drive READY input is valid within 500 ns
       after the drive is selected (DRIVE SELECT true) and after the
       power on delay.

  6.   The drive is selected within 1 us after the assertion of
       DRIVE SELECT, if the power on sequence is complete. The drive
       will be the deselected within 1 us after the negation of
       DRIVE SELECT.

  7.   The drive activates the data cable DRIVE SELECTED signal within
       1 us after receipt of DRIVE SELECT if the drive is selected.
       The drive negates DRIVE SELECTED within 1 us after the
       DRIVE SELECT signal is negated.

  8.   DRIVE SELECT must be valid 100 ns minimum before the first step
       pulse is received and 100 ns minimum after the last step pulse
       is received.

  9.   At the completion of a write operation, DRIVE SELECT must
       remain asserted for 1 us.

 10.   When the DRIVE SELECT line is asserted, a head change occurs,
       thus requiring a delay of 5 us before a read or write operation
       can be initiated.


 J7  Radial Select
 -----------------
   9-10  OPEN      Radial disable
         CLOSED    Radial enable



 J7  External Spindle Clock (Option)
 -----------------------------------
  11-12  OPEN      Spindle Sync disabled
         CLOSED    Spindle Sync enabled

 The external spindle clock options allow for synchronized rotation
 of a few disk drives in a system. Each drive can be configured to one
 of the following modes:

      a. Use internal spindle clock, output spindle reference clock.

      b. Use internal spindle clock with a line terminator.

      c. Use external spindle clock without the line terminator.



 Motor On Command (Optional)
 ---------------------------
 When the Motor On Command option is installed, the Motor On input
 line controls the drive spin up and spin down operation. This line is
 terminated with 220 ohm to +5V and with 330 ohm to ground. The
 terminator is not removable. The Motor On signal is asserted when
 high. There is no need to select the drive for spin up/spin down
 operation.



**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
SEAGATE  ST1100/ST1150R  PRODUCT MANUAL 36136-001, REV. B

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

 Drive mounting
 --------------

     horizontally             vertically
   +-----------------+   +--+             +--+ +------------------+
   |                 |   |  +-----+ +-----+  | |                  | x
   |                 |   |  |     | |     |  | x+----------------+x
 +-+-----------------+-+ |  |     | |     |  | ||x              x||
 +---------------------+ |  |     | |     |  | ||  x          x  ||
                         |  |     | |     |  | ||    x      x    ||
      x           x      |  |     | |     |  | ||      x  x      ||
 +------x------x-------+ |  +-----+ +-----+  | ||       xx       ||
 +-+------x--x-------+-+ +--+             +--+ ||     x    x     ||
   |       xx        |                         ||   x        x   ||
   |     x    x      |                         || x            x ||
   +---x--------x----+                         |x                x|
     x            x                           x++----------------++x
      UNACCEPTABLE!                                UNACCEPTABLE!
      Never install PC board on the Top!



 Drive Orientation
 -----------------
 The permissible drive mounting orientations include operation in the
 horizontal plane with PCB down and in the vertical plane. Mounting
 with either end down (front or rear) is not permissible.


 The SWIFT is designed, manufactured, and tested with a "Plug-in and
 Play" installation philosophy. Basically, this philosophy minimizes
 the requirements for highly trained personnel to integrate the SWIFT
 into the OEM's system, wether in a factory or field environment.


 Front Panel
 -----------
 The SWIFT is available with a black front panel. The panel has a
 single green rectangular lens through which ligth from a LED mounted
 on the PWA radiates. The LED indicates the drive is selected when
 glowing. A flashing LED indicates the presence of a nonrecoverable
 fault. A fault indication is displayed irrespective of DRIVE SELECT
 status.


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

 Sway
 ----
 The sway of the HDA left to right and front to rear is within the
 envelope. The sway of the HDA up and down is   0.05 inch outside the
 envelope.


 Interface Cabling Options
 -------------------------

 View A
    +---------------------Host-Controller---------------------+
    |                                                         |
    |Data Command   Data Command  Data Command   Data Command |
    +--+-----+--------+-----+--------+-----+--------+-----+---+
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
    +-++-+--++-+-+ +-++-+--++-+-+ +-++-+--++-+-+ +-++-+--++-+-+
    | |R |  | T| | | |R |  | T| | | |R |  | T| | | |R |  | T| |
    | +--+  +--+ | | +--+  +--+ | | +--+  +--+ | | +--+  +--+ |
    |   SWIFT    | |   SWIFT    | |   SWIFT    | |   SWIFT    |
    +------------+ +------------+ +------------+ +------------+

    Each cable command length must not exceed 20 feet (6.10m). Each
    data cable length must not exceed 20 feet (6.10m).


    T  indicates terminator resistor pack.
    SWIFT data cables are permanently terminated.
    R  indicates discrete terminator.


 Radial Configuration
 --------------------
 View A shows each drive interfaced to its own command cable, which
 allows interfacing of any number of drives and a variety of
 system operational techniques. Each drive has its data cable and
 command cable radially connected to the host controller. The length
 of each individual cable must not exceed 20 feet (6.10 meters).
 Terminator resistors must be installed in the host controller for
 each data cable and for each command cable.


 View B
    +--------------Host Controller----------------------------+
    |                                                         |
    |Data Command   Data          Data             Data       |
    +-+------+-------+--------------+---------------+---------+
      |      |       |              |               |
      |      |       |              |               |
      |      |       |              |               |
      |      |       |              |               |
      |      +-------+Command+------+-------+Command+-------+
    +++-+----+---+ +++-+-----+--+ +++-+-----+--+  +++-+----++-++
    ||R |        | ||R |        | ||R |        |  ||R |    | T||
    |+--+        | |+--+        | |+--+        |  |+--+    +--+|
    |   SWIFT    | |    SWIFT   | |   SWIFT    |  |   SWIFT    |
    +------------+ +------------+ +------------+  +------------+

    Total command cable length must not exceed 20 feet (6.10m). Each
    data cable length must not exceed 20 feet (6.10m).

   T  indicates terminator resistor pack.
   SWIFT data cables are permanently terminated.
   R  indicates discrete terminator.


 Daisychain Configuration
 ------------------------
 A daisychain configuration incorporates parallel interfacing of the
 disk drives on a common command cable. A maximum of four drives may
 be daisychained on the command cable. Only the drive which is
 selected by the host system has its control and data signals enabled
 through this common interface. View B consists of four SWIFT disk
 drives only. A terminator resistor pack is required in the host
 controller for each data cable. Only the last SWIFT in the daisychain
 requires a terminator resistor pack for the command cable. Terminator
 resistor packs for the command cable or other drives are removed. The
 total combined command cable length (from the controller to the first
 drive, to the second and subsequent drives) must not be more than 20
 feet (6.1 meters).


 DC Cable and Connector
 ----------------------
 The SWIFT receives DC power through a 4 pin connector mounted on the
 HDA. Recommended part numbers for the mating connector are included
 below, but equivalent parts may be used.

 Type of cable:      18 AWG
 Connector:          AMP 1-480424-0
 Contacts:           AMP 60619-4 (Loose Piece); AMP 61117-4 (Strip)


 Ground Connection
 -----------------
 A quick disconnect, Amerlock MTL-1802-A, is provided on the drive
 chassis.

 Type of cable:      26-24 AWG
 Connector:          WALDOM ST-2750
 Contacts:           Quick Disconnect (Ground)



 Data Cable and Connector
 ------------------------
 The I/O connector for the data interface is a 20 pin board edge
 connector. The odd pins are located on the side of the printed
 circuit board facing towards the HDA. The even pins are on the side
 of the printed circuit board facing away from the HDA. A key slot is
 provided between pins 3 and 5. CDC recommends keying this connector
 to prevent installing it upside down.

 Recommended part numbers for the mating connector are included below,
 but equivalent parts may be used.

 Connector:          20 pin, 3M-3461-0001, AMP 88373-6
 Cable:              Flat Cable (Stranded AWG 28) 3M-3365-20
                     Flat Cable (Stranded AWG 28) 3M-3517-20 (Shielded
                     Cable)
 Key:                AMP 583274-1, 3M-3439-0000



 Command Cable and Connector
 ---------------------------
 The I/O connector for the command interface is a 34 pin board edge
 connector. The odd pins are located on the front side of the
 printed circuit board facing towards the HDA and are connected to the
 ground plane. The even pins are on the side of the printed circuit
 board facing away from the HDA. A key slot is provided between pin 3
 and 5. CDC recommends keying this connector to prevent installing it
 upside down.

 Recommended part numbers for the mating connector are included below,
 but equivalent parts may be used.

 Connector:          34 pin, 3M-3463-0001, AMP 88373-3
 Key:                AMP 583274-1, 3M-3439-0000
 Cable:              Flat cable (Stranded AWG 28) 3M-3365-34
                     Flat cable (Stranded AWG 28) 3M-3517-34 (Shielded
                     Cable)
                     Spectra Strip Twist'n Flat 455-248-34 (Stranded
                     AWG 28 Twisted Pair)



 Cable and Connector
 -------------------
 The connector for the spindle reference clock signal is a 2 pin 2.0
 mm pitch connector. The recommended connector consists of:

                 a.  Du Pont Housing   69305-002
                 b.  Du Pont Terminal  77138-001

 or equivalent.

 The cable consists of two 28 AWG wires. The maximum cable length is
 20 feet (6.1 meters).

 The external spindle clock connector header is mounted on the disk
 drive main PCB. J7 pins 11 and 12 are used for the external spindle
 clock connection.


 Interface Drivers/Receivers
 ---------------------------
 The SWIFT uses both single ended and balanced differential signals on
 the I/O. The data signals use balanced differential drivers and
 receivers. All other signals use single ended drivers and receivers.


 Single Ended Drivers/Receivers
 -------------------------------
 Transmitter Characteristics
 The SWIFT uses a custom driver to transmit status to the host. This
 driver is capable of sinking a current of 24 mA with a low level
 output voltage of 0.4 V.


 Receiver Characteristics
 The SWIFT uses a custom receiver with hysteresis gate as a line
 receiver. The input of each receiver is terminated in a 220/330 ohm
 resistor network.


 Terminator Characteristics
 The terminator consists of a resistor module which plugs into a
 socket in the last drive in a daisychain. Each drive is furnished
 with a terminator. Terminators must be removed from all except the
 last drive on the cable prior to daisychain operation. The terminator
 can be easiliy removed with tweezers or needlenose pliers. Terminator
 installation, however, requires some disassembly of the drive. An
 equivalent terminator must be provided in the controller on each
 input signal line from the drive to the controller. Only the Command
 cable resistor module is removable.


 Balanced Differential Drivers/Receivers
 ---------------------------------------
 Transmitter Characteristics
 The SWIFT uses 75158 type balanced differential drivers. A signal on
 the interface is defined as asserted when the "+" output is more
 positive than the "-" output.


 Receiver Characteristics
 ------------------------
 The SWIFT uses 75157 type balanced differential receivers. A signal
 on the interface is defined as asserted when the "+" input is more
 positive than the "-" input.


 Terminator Requirements
 -----------------------
 Each differential receiver in the drive is terminated with a 100 ohm
 resistor. The terminator is a Beckman Industrial P/N L105C221/331F or
 equivalent. An equivalent terminator must be provided in the
 controller on each input signal line from the drive to the
 controller.


 Driver and Receiver
 -------------------
 The external spindle clock signal utilized a balanced differential
 driver and receiver the same as those used for data transfer. The +
 signal is connected to J7 Pin 11 and the - signal is connected to J7
 pin 12. The terminator used is the same as the one used for data
 transfer.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
SEAGATE  ST1100/ST1150R  PRODUCT MANUAL 36136-001, REV. B

 General Description
 -------------------
 The SWIFT is a member of a family of low cost, high performance,
 highly reliable, random access storage devices designed to meet the
 needs of the OEM marketplace.

 The SWIFT interface consists of a 34 pin command interface cable and
 a 20 pin data interface cable which is compatible with the industry
 standard ST506/ST412 disk drive interfaces. The 34 pin command inter-
 face is designed to allow daisy chained or radial connections to
 additional SWIFT disk drives.


 Standards
 ---------
 The SWIFT has been developed as a system peripherals to the highest
 standards of design and construction. The SWIFT depends upon its host
 equipment to provide adequate power and environment in order to
 achieve optimum performance and compliance with applicable
 industry and governmental regualations. Special attention must be
 given in the areas of safety, power distribution, shielding, audible
 noise control, and temperature regulation.

 The SWIFT complies with CDC standards.


 The SWIFT is a UL Recognized component per UL478 and a CSA Certified
 product per CSA C22.2, No. 220-M1986. It also meets the requirements
 of DIN IEC 380/IEC 435/IEC 950/VDE 0806/8.81.

 The SWIFT, as delivered, is designed for system integration before
 use. It is supplied as a Class A Computing Device per the FCC Rules
 and Regulations, Part 15, Subpart J, governing EMI of computing
 devices.


 The SWIFT uses a dedicated landing zone at the innermost radius
 of the media where is no user data, thus eliminating the possibility
 of destroying or degrading customer data. Read/write heads are auto-
 matically moved to the landing zone upon loss of power.

 The SWIFT incorporates an automatic shipping look which prevents
 potential damage to the heads and discs caused by movements during
 shipping and handling. The shipping lock is automatically disengaged
 when power is applied to the drive and nominal spindle speed is
 achieved.

 The SWIFT decodes Track 0 location from the dedicated servo surface
 thereby eliminating mechanical transducer adjustments and
 related reliability concerns.

 The SWIFT uses a high performance actuator assembly consisting of a
 low inertia, patented straight arm driven by a highly efficient
 pancake coil assembly. This actuator mechanism provides excellent
 performance with minimal power dissipation.


 Media Description
 -----------------
 The media used in the SWIFT has a diameter of approximately 95 mm.

 Each data surface has a total of 1072 tracks and is capable of
 recording 11,165,952 (16,748,928 RLL) bytes of unformatted data.

 Media defects are characterized as beeing either correctable or
 uncorrectable as a function of the type and magnitude of the media
 flaw. Various error correction codes may be implemented to correct
 errors in the data read from the disk. However, the code chosen
 should be consistent with Control Data media testing and
 certification methods. In the SWIFT media certification is performed
 using the following standards:

            An error burst of 11 bits or less is a correctable error.

            An uncorrectable error is one greater than 11 bits in
            length.

 Host systems using the SWIFT should have, as a minimum, resident
 capabilities to recognize and map defective tracks and perform track
 reallocation routines.

 At the time of shipment from the point of manufacture, the SWIFT
 recording surfaces meet the following requirements.

       1. 1072 total tracks per surface.

       2. Track 0 to be error free on each data surface.

       3. 15 bad tracks per surface maximum (MFM Models).
          20 bad tracks per surface maximum (RLL Models).

       4. Accumulative defects not to exceed 1 per megabyte, based on
          total available unformatted drive capacity.


 Service Tools
 -------------
 No special tools are required for site installation or recommended
 for site maintenance.


 Defect and Error Management
 ---------------------------
 The SWIFT, as delivered, complies with all aspects of this
 specification. The read error rate and specified storage capacity
 are not dependent upon the use of defect management routines.
 However, carefully chosen defect management methods can significantly
 enhance overall system performance. The application of error
 correction codes (ECC), and/or sector reallocation permits the
 continued use of the major portion, or perhaps all of a track when a
 defect is found.

 ECC is highly recommended since the majority of defects are correct-
 able. If ECC is not used, then all flagged defects will be essenti-
 ally uncorrectable and must be reallocated. Sector or track realloca-
 tion schemes are effective methods for relocating media defects.
 Sector reallocation in general is more efficient and may offer
 significant performance improvement.



 Acoustic Noise Level
 --------------------
 Acoustic noise power level of the SWIFT should be less than TBD
 numbers bels during idle/operation mode. Equivalent typical average
 sound pressure level should be less than TBD numbers dba when
 measured with microphone at a distance of one meter from the drive.


 Custom Formatting
 -----------------
 CDC maintains custom formatting capability which can accommodate many
 of the unique formats used in the Winchester marketplace. A majority
 of special format requirements can be implemented as specified by the
 customer. Unique format requirements should be identified as soon as
 possible to facilitate timely implementation.


 Drive/Receiver Characteristics
 ------------------------------
 Interface signals levels and logical sense at the SWIFT I/O
 Connector are defined as follows:

 Logic Level                   Drive Output         Receiver Input
 --------------------------------------------------------------------
 High (false/negated) (0)      2.5 V;   5.25 V      2.0 V;   5.25 V
 Low  (true/asserted) (1)      0.4 V;   0.0 V       0.5 V;   0.0 V

 The difference in the voltages between input and output signals is
 due to the losses in the cable.



 Seek Time
 ---------
                                                Models
                                          |16.5 MS |25 MS   |
        ----------------------------------+--------+--------+
        Track-to-track         msec. max. |   4    |   5    |
                       Average msec. typ. |  15    |  22    |
                       Average msec. max. |  16.5  |  25    |
        Latency                msec. avg. |   8.33 |   8.33 |
        ----------------------------------+--------+--------+

 Seek time is defined as the time required from the receipt of a seek
 or position command by the SWIFT until the drive signals the
 controller that it is ready to perform another seek or a read/write
 function on the new cylinder. Average seek time is determined by
 dividing the sum of the time for all possible movements by the total
 number of movements.


 Spindle Speed and Latency
 -------------------------
 The spindle speed is 3600   0.5% r/min. The speed tolerance includes
 motor performance and motor control circuit tolerances.

 The average latency time is 8.33 milliseconds, based on a nominal
 disc speed of 3600 r/min. The maximum latency time is 16.75 milli-
 seconds based on a minimum disc speed of 3582 r/min.


 Read Data Transfer Rate
 -----------------------
 The nominal read serial data transfer rate is 5.0 Mbits per second,
 for MFM models and 7.5 Mbits per second for the RLL models.


 Power Sequencing
 ----------------
 Power sequencing is not required for the SWIFT. The SWIFT protects
 against inadvertent writing during power up and down. Daisychain
 operation requires that power be maintained on the terminated unit
 to ensure proper termination of the peripheral I/O cables.

 Power sequencing can be obtained by using the motor on command
 option, if the drive has been configured for its use.


 Heat/Power Dissipation
 ----------------------
 Each SWIFT will typically dissipate 10 watts (34 BTU per hour) of
 power during operation (seeking). Idle mode power dissipation is less
 than 8 watts, typically.


 Temperature
 -----------
 50*F to 122*F (10*C to 50*C) (dry air) operating ambient with a
 maximum gradient of 18* F (10* C) per hour. Above 1000 feet (305
 meters) altitude the maximum temperature is derated linearly to 112*F
 (44* C) at 10,000 feet (3048 meters). Cabinet packaging designs
 must provide ample air circulation around the SWIFT to make sure
 environmental limits are not exceeded as a result of heat transfer
 from other system components. Operating ambient for specification
 purposes is defined as the environment immediately surrounding the
 SWIFT. The temperature of the HDA is restricted to a maximum of
 TBD during operation. System cooling consideration should
 avoid large thermal gradients between points A and B.


 Air Cleanliness
 ---------------
 The SWIFT is designed to operate in a typical office environment
 with minimum environmental control.


 Electromagnetic Emissions
 -------------------------
 The SWIFT meets the performance requirements for electromagnetic
 emissions set forth in CDC-STD 1.03.208 which assures compliance
 with FCC rules and regulations.


 Chassis/DC ground separation
 ----------------------------
 The SWIFT is provided with the chassis groung tied to DC logic
 ground. An option is provided for the user to isolate the chassis and
 logic grounds. This option may be beneficial in reducing ground
 induced noise in some system applications.


 Write Precompensation
 ---------------------
 RLL write data must conform to the conventional RLL encoding rules
 and must write precompensated by   12 ns per the industry standard
 RLL data write precompensation rules. Write precompensation is re-
 commended on all tracks; however, write precompensation must be
 performed on tracks greater than Track 300.

 No write precompensation is required for MFM.


 Options
 -------
 All options are either incorporated or packaged at the manufacturing
 facility.


 Reliability
 -----------
 The following reliability specifications require that correct
 host/drive operational interface has been implemented, including all
 interface timings, power supply voltages, environmental conditions,
 and appropriate data handling circuits in the host system.

 MTBF                     30,000 hours
 Service Life             5 years
 Preventive Maintenance   None required