
2 1 0 5   S    MICROPOLIS
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 3.5"/HH               Cylinders    1748|     |     |
Capacity form/unform   560/  647 MB        Heads           8|     |     |
Seek time   / track  10.0/ 2.0 ms          Sector/track     |     |     |
Controller           SCSI2 SI/FAST         Precompensation
Cache/Buffer           512 KB READ-AHEAD   Landing Zone
Data transfer rate          MB/S int       Bytes/Sector      512
                     10.000 MB/S ext SYNC
Recording method     RLL                            operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C         5 50    |    -40 65
Power: sleep              W     Humidity     %        10 90    |     10 95
       standby            W     Altitude    km    -0.061  3.048| -0.305 15.250
       idle          11.5 W     Shock        g        10       |     60
       seek          13.0 W     Rotation   RPM      5400
       read/write    11.7 W     Acoustic   dBA        36
       spin-up            W     ECC        Bit   64
                                MTBF         h     300000
                                Warranty Month
Lift/Lock/Park     YES          Certificates                                  

**********************************************************************
                        L   A   Y   O   U   T
**********************************************************************
MICROPL. 2112/2108/2105-S  TECHNICAL MANUAL 135812 REV. A

   Single-Ended Interface / Device Electronics Board 135692
  +---------------------------------------------------------+
  |                                                     RN1+|XX
  |                                        J2 Mounted   ++|||XX
  |                                        on solder   J2||||XX
 ++  ++W14 LED Option                      side         ++++|XX
 ++++++                                                   RN2XX J1
  |++J9 Remote LED                                    W2++|||XX
  |                                    ID0+-+         W1|||||XX
  |                                    ID1| |           ++++|XX
  |                                    ID2| |            W3+|XX
  |                                    PTY| |             ++|XX
  |                                    WP | |           RN3+|XX
  |                                    SP0| |             |||XX
  |                                    SP1+-+             |||XX1
  |                                            +W12       ++|
  |                                            ++           |
  |                          +-------+         +W13         |XX J3
  |                          +++++++++         ++           |XX Power
  +---------------------------------------------------------+






   Single-Ended Interface/ Device Electronics Board 135792
  +---------------------------------------------------------+
  |                                                     RN1+|XX
  |             ++J7                       J2 mounted   ++|||XX
  |             ++LED Connector            on the      J2||||XX
  ++          ++W4                         solder side  ++++|XX
  ++          ++LED Option                              W2++|XX J1
  |++ID2                                                W1|||XX
  |+|ID1 SCSI ID                       ID0+-+             ++|XX
  |++ID0                               ID1| |           W3++|XX
  |                                    ID2| |             ++|XX
  |                                    PTY| |           RN2+|XX
  |                                    WP | |  ++         |||XX
  |                                    SP0| |  |RESERVED  |||XX
  |                                    SP1+-+  ++         ++|  1
  |                                            +W10         |
  |                                            ++           |
  |                          +-------+         +W11         |XX J3
  |                          +++++++++         ++           |XX Power
  +---------------------------------------------------------+  1







   Connector J2 (detail)
   ---------------------
   Pin 1 Slave Sync; 2 Not Connected; 3 Master Sync; 4 Ground;


             ++-+-+-------------------------
             || +-J4 Frame Ground Connector
             ||
             || +----------+
             || | ++++++++ J2
             ||++-+1+2+3+4-+-------------
             ||| o o o o o o o o o o o o
             ||| o o o o o o o o o o o
             ||+---------J1-----------
             ||    +-----------------
             |+----+
             +---------------------


 Note: There are two different Device Electronics board layouts
 implemented for the single-ended interface. These layouts are
 identified 135692 and 135792; this number can be found on the board
 part number label where it will be of the form 135692-xx-x or
 135792-xx-x. These boards are functionally equivalent. The 135792 is
 the more recent and incorporates active termination and additionally
 SCSI ID selection jumpers.



**********************************************************************
                      J   U   M   P   E   R   S
**********************************************************************
MICROPL. 2112/2108/2105-S  TECHNICAL MANUAL 135812 REV. A

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

 x = default

 Device Electronic Board 135692
 ------------------------------


 SCSI ID
 -------
   +----------+-----------------------+
   | SCSI ID  |        Jumpers        |
   |          | ID2   | ID1   | ID0   |
   +----------+-------+-------+-------+
   |    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  |
   +----------+-------+-------+-------+
   | x  7     | CLOSED| CLOSED| CLOSED|
   +----------+-------+-------+-------+

 Up to eight devices (a host and seven targets) can be attached to
 the SCSI bus. The 2112/2108/2105-S each has three ID jumpers. These
 jumpers are used to assign one of the eigth SCSI ID bits (0 - 7) to
 the drive.

 In multiple-device systems, each drive must have its own unique ID.



 SPIN 0  Spindle Control Option
 ------------------------------
 A jumper at SPIN 0 is used to select the spindle control option.

 Note: Do not install jumpers at both SPIN 0 and SPIN 1.

 When a jumper (SPIN0 ) is installed, the drive must wait for an
 interface START UNIT command to start the spindle motor.

 When a jumper is not installed, (the factory default configuration),
 the drive automatically starts the spindle motor at power-on or after
 a delay related to the device SCSI ID, if enabled by the SPIN 1
 jumper.


 SPIN 1  Spindle Delay Option
 ----------------------------
 A jumper at SPIN 1 is used to select the spindle delay option
 (spindle start-up is delayed upon the SCSI ID). Delay time per ID is
 12 seconds.

 Note: Do not install jumpers at both SPIN 0 and SPIN 1.

 When a jumper is installed, spindle delay is enabled.

 When a jumper is not installed, (the factory default configuration),
 spindle delay is disabled.


 PARITY  Bus Parity Check Option
 -------------------------------
     PARITY CLOSED  The drive neither generates nor detects parity.
              OPEN  The drive generates parity and enables parity
                    detection. (Factory default)


 WPROT  Write Protect Option
 ---------------------------
     WPROT CLOSED  The drive is write protected. CAUTION: The
                   drive can still be formatted.
           OPEN    The drive is not write protected. (Factory
                   default configuration)


 W1/W2/W3  Bus Termination Power Option
 --------------------------------------

   +-----------------------+------------------------------------+
   |        Jumpers        |                                    |
   |  W1   |  W2   |  W3   |                                    |
   +-------+-------+-------+------------------------------------+
   | CLOSED| OPEN  | OPEN  |The drive provides local terminator |
   |       |       |       |power.                              |
   +-------+-------+-------+------------------------------------+
   | OPEN  | CLOSED| OPEN  |Host system provides local          |
   |       |       |       |termination power.                  |
   +-------+-------+-------+------------------------------------+
  x| CLOSED| OPEN  | CLOSED|Drive provides local terminator     |
   |       |       |       |power and terminator power to BUS.  |
   +-------+-------+-------+------------------------------------+



 W12/13  Spindle Sync Termination
 --------------------------------
 Jumpers installed (CLOSED) at W12 and W13 provide termination for the
 Spindle Synchronization signals (Slave Sync and Master Sync respect-
 ively).

 When the Spindle Synchronization option is to be implemented,
 jumpers W12 and W13 are removed from all drives except the last drive
 on the cable.

 The Rotational Position Locking field (MODE SELECT command, Page Code
 04h) is used to specify spindle synchronization operation.

 Unsynchronized: If the drive is set to Unsynchronized (RPL = 00b), it
 ignores the SLAVE SYNC signal.

 Slave: If the drive is set to Slave (RPL = 01b), it does not generate
 the MASTER SYNC signal or the SLAVE SYNC signal but synchronizes its
 index to the SLAVE SYNC signal (J2, pin 1) generated by an external
 source.

 Master: If the drive is set to Master (RPL = 10b), it generates the
 SLAVE SYNC signal (J2, pin 1) for the slaves.

 Master Control: If the drive is set to Master Control (RPL = 11b), it
 generates the MASTER SYNC signal (J2, pin 3). This output is used by
 the controller to generate the SLAVE SYNC signal (J2, pin 1) for the
 slaves.


 W14  Remote LED Option
 ----------------------
 A jumper at W14 is used to select the front bezel LED option.

   x CLOSED  The front bezel LED is enabled and remote LED connector
             J9 is disabled.
     OPEN    The front bezel LED is disabled; and remote LED connector
             J9 is enabled.


 Interface Termination
 ---------------------
 Terminators installed at RN1, RN2, and RN3:
 x Drive provides termination for the interface lines.

 Terminators ommitted:
   Drive does not provide termination for the interface lines.

 -------------------------------------------------------------------

 Device Electronics Board 135792
 -------------------------------

 NOTE: There are two identiacal groups of address jumpers on the
 Device Electronics Board; one group is near the LED, and the other
 group is in line with SP0, SP1 WP, and PTY. USE EITHER GROUP FOR
 ADDRESS SELECTION BUT - NOT - USE BOTH AT THE SAME TIME.

 Interface termination on the 135792 is active termination (SCSI-2
 alternative 2 termination). Termination can be disabled electrically
 (by jumpers) and physically (by removing resistor packs RN1 and RN2,
 preferred method).


 SCSI ID
 -------

   +----------+-----------------------+
   | SCSI ID  |        Jumpers        |
   |          | ID2   | ID1   | ID0   |
   +----------+-------+-------+-------+
   |    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  |
   +----------+-------+-------+-------+
   | x  7     | CLOSED| CLOSED| CLOSED|
   +----------+-------+-------+-------+

 Up to eigth devices (the host and seven targets) can be attached to
 the SCSI Bus. The 2112S, 2108S, and 2105S have three ID
 jumpers ID0, ID1, and ID2. The jumpers are used to assign one of
 eight SCSI ID bits (0-7) to the drive. In multiple-device systems,
 each drive must have its own unique ID.


 RN1/RN2  Interface Termination
 ------------------------------
 Terminators INSTALLED at RN1 and RN2 (Default).
     Drive provides termination for the interface lines.

 Terminators at RN1 and RN2 omitted.
     Drive does not provide termination for the interface lines.


 W1/W2/W3  Bus Termination Power Option
 --------------------------------------
        W1  CLOSED  Drive provides local terminator power.
        W2  CLOSED  Host system provides local terminator power.
 W1 and W3  CLOSED  Drive provides local terminator power and
                    terminator power to the BUS. (default)


 W4  Remote LED Option
 ---------------------
 x   W4  CLOSED  LED on Device Electronics board is enabled.
         OPEN    LED (user supplied) at J7 is enabled.



 W10/W11  Spindle Sync Termination
 ---------------------------------
 x  W10/W11  CLOSED  Spindle Sync signal is terminated.
             OPEN    Spindle Sync is not terminated.

 When this option is to be implemented, the jumpers are removed from
 all drives except the last drive on the cable.


 SP0/SP1  Spindle Control Option
 -------------------------------
    SP0  CLOSED
    SP1  OPEN    Spindle motor starts when START UNIT command is
                 received.
 x  SP0  OPEN    Spindle motor starts at power-on.



 SP0/SP1  Spindle Delay Option
 -----------------------------
    SP1  CLOSED
    SP0  OPEN    Spindle start-up is delayed based on SCSI ID (12
                 seconds per ID).
 x  SP1  OPEN    Spindle start-up delay is disabled.



 WP  Write Protect Option
 ------------------------
     WP  CLOSED  Drive is write protected.
 x       OPEN    Drive is not write protected.



 PTY  Bus Parity Check Option
 ----------------------------
      CLOSED  Drive neither generates nor detects parity.
 x    OPEN    Drive generates parity and has parity detection
              enabled.


 --------------------------------------------------------------------


 J3   DC Power and pin connector assignments
 -------------------------------------------
 -------------------+
 --+  +-----J3-----+|  pin 1    +12 VDC
  1|  | 4  3  2  1 ||  pin 2    +12 Volts Return
  -+  +------------+|  pin 3    + 5 Volts Return
  ------------------+  pin 4    + 5 VDC



**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
MICROPL. 2112S/D/2108S/2105S  TECHNICAL MANUAL 135812 REV. A

 Notes on Installation
 =====================

 Recommended mounting orientations
 ---------------------------------

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

 The drives use industry-standard mounting for 3 -inch full-height
 Winchester disk drives.

 The drives are designed such that the outer frame should be hard-
 mounted to the host equipment; no additional/external shock mounts
 should be used.

 Recommend orientation is vertical on either side, or horizontal with
 the Device Electronics board down.

 No matter what mounting orientation is used, Micropolis specifies
 that the maximum HDA casting temperature not exceed 60*C (140*F).

 If the HDA casting temperature measurement cannot be made, the
 ambient air temperature around the drive must be kept at or below
 50*C (122*F).

 Caution:
 The mounting screws must be selected so that they do not penetrate
 the bottom mounting holes by more than 0.20 inches or the side mount-
 ing holes by more than 0.156 inches.

 Screws that are too long will short to PCBA components and/or prevent
 proper operation of the shock mount system.


 Mounting holes
 --------------
 3 per side and 4 on bottom #6-32 UNC-2B thru.


 Multiple-Drive Systems
 ----------------------
 Up to seven drives may be connected to a single host controller/
 formatter. Control signals at J1 are transmitted via standard,
 daisy-chain interconnection. Data signals at J2 are transmitted via
 radially connected data-transfer lines.

                                             Drive #1
  +------HOST------+                 +-----------------+
  | +-----------+  +--+-SCSI-BUS-----+ J1              |
  | |Terminators|  |  |       +------+ J3    J4        |
  | +-----------+  |  |       |      +--------+--------+
  |                |  |       |               +------------------+
  +----------------+  |       |              Drive #2            |
                      |       |      +-----------------+         |
                      +-------+------+ J1              |         |
                      |       o------+ J3    J4        |         |
                      |       |      +--------+--------+         |
                      |       |               +------------------o
                      |       |              Drive #3            |
                      |       |      +-----------------+         |
                      +-------+------+ J1              |         |
                      |       o------+ J3    J4        |         |
                      |       |      +--------+--------+         |
                      |       |               +------------------o
                      |       |              Drive #4            |
                      |       |      +--------------+--+         |
                      +-------+------+ J1           |T |         |
                              o------+ J3    J4     +--+         |
           ---DC-VOLTAGES-----+      +--------+--------+         |
           ---GROUND--------------------------o------------------+

 T = TERMINATORS

 Terminators are installed ONLY in the last physical drive in the
 control chain.

 Connection J4 is provided for grounding; system characteristics
 determine the proper ground connection.


 J1 Signal Connector
 -------------------
 Recommended Cable:    3M Scotchflex 3365/50 or equivalent
 Mating connector:     3M P/N 3425-3000 or equivalent


 J2 Spindle Synchronization connector
 ------------------------------------
 Recommended mating connector: MOLEX 10-11-2043 or equivalent
 Pins:                         MOLEX 08-50-0005
 Suggested wire size:          22-24 AWG for all pins


 J3 Power Connector
 ------------------
 Recommended mating connector: AMP 1-480424-0 or equivalent
 Pins:                         AMP 350078-4
 Suggested wire size:          18 AWG (minimum) for all pins.


 J4 Ground Connector
 -------------------
 3/16-inch spade lug J4 is provided for grounding. System character-
 istics determine proper ground connection.

 Recommended mating connector: AMP 60972-2 or equivalent


 J7 Remote LED Connector
 -----------------------
 Recommended mating connector: Dupont 69305-002 or equivalent
 Pins:                         Dupont 77138-001
 Suggested wire size:          26-30 AWG for all pins


 Differential Terminator
 -----------------------
 Suggested Terminator: Methode DM 103-01-0 or equivalent


 135692 SINGLE-ENDED Interface Electrical Characteristics
 --------------------------------------------------------
 Interface control and status signals are digital (open collector TTL)
 using industry-standard transmitters and receivers.

 The assigned signals are terminated with 220 ohms to +5V (nominal)
 and 330 ohms to ground at each end of the cable.

 All signals use open-collector or tri-state drivers.

 Single-ended drivers and receivers allow a maximum cable length of
 six meters (primarily for connection within a cabinet).

 Signal transmission requires a single 50-conductor (flat or twisted
 pair) cable. A characteristic impedance of 100 ( 10%) ohms is
 recommended.

   a. Input Characteristics

      1)  Signal true = 0.0 VDC to 0.8 VDC
      2)  Maximum total input load = -0.4 milliamps at 0.5 VDC
      3)  Signal false = 2.0 VDC to 5.25 VDC
      4)  Minimum input hysteresis = 0.2 VDC

   b. Output Characteristics

      Each driven signal has the following characteristics when
      measured at the interface connector.

      1)  Signal assertion = 0.0 VDC to 0.5 VDC
      2)  Minimum driver output capability = 48 milliamps (sinking) at
                                             0.5 VDC.
      3)  Signal negation = 2.5 VDC to 5.25 VDC

   c. Terminator Power (TERMPWR at Pin 26)

      Terminator Power has the following requirements:

      V(TERM) = 4.25 VDC to 5.25 VDC

      800 milliamps minimum source drive capability, with 1.0 amp
      recommended current limiting (e.g., a fuse).

      1.0-milliamp maximum bus loading (except for the purposes of
      providing power to an internal terminator).

 The drive provides keyed connectors to prevent accidental grounding
 or misconnection of terminator power.


 135792 SINGLE-ENDED Interface Electrical Characteristics
 --------------------------------------------------------
 Interface control and status signals are digital (open collector TTL)
 using industry-standard transmitters and receivers.

 For active termination, the assigned signals are terminated with 110
 ohms to +2.85V (nominal). For passive termination, the assigned
 signals are terminated with 220 ohms to +5V (nominal) and 330 ohms to
 ground. All signals use open-collector or tri-state drivers.
 Single-ended drivers and receivers allow a maximum cable length of
 six meters (primarily for connection within a cabinet).
 Signal transmission requires a single 50-conductor (flat or twisted
 pair) cable. A characteristic impedance of 100 ( 10%) ohms is
 recommended.

   a. Input Characteristics

      Each of the drive's signal receivers has the following
      characteristics when measured at the interface connector.

      1) Low-level input voltage (Signal true) = 0.0 VDC to 0.8 VDC
      2) High-level input voltage (Signal false) = 2.0 VDC to 5.25 VDC
      3) Low-level input current = -0.4 milliamps at 0.5 VDC
      4) High-level input current = 0.1 milliamps at 2.7 VDC
      5) Minimum input hysteresis = 0.2 VDC
      6) Maximum input capacitance = 25 pF

   b. Output Characteristics

      Each of the drive's signal drivers has the following
      characteristics when measured at the interface connector.

      1) Low-level input coltage (Signal assertion) = 0.0 VDC to 0.5
                                                      VDC
      2) High-level input voltage (Signal negation) = 2.5 VDC to 5.25
                                                      VDC
      3) Minimum driver output capability = 48 milliamps (sinking) at
                                            0.5 VDC.

   c. Terminator Power (TERMPWR at Pin 26)

      Terminator Power has the following requirements:

      V(TERM) = 4.25 VDC to 5.25 VDC

      800 milliamps minimum source drive capability, with 1.0 amp
      recommended current limiting (e.g., a fuse).

      1.0-milliamp maximum bus loading (except for the purposes of
      providing power to an internal terminator).

 The drive provides keyed connectors to prevent accidental grounding
 or misconnection of terminator power.


 DIFFERENTIAL Interface Electrical Characteristics
 -------------------------------------------------
 Differential interface signals consist of two signal lines which are
 denoted +SIGNAL and -SIGNAL.

 A signal is defined as true when the +SIGNAL is more positive than
 the -SIGNAL.
 A signal is defined as false when the -SIGNAL is more positive than
 the +SIGNAL.

 Differential drivers and receivers allow a maximum cable length of
 25 meters.

 Signal transmission requires a single 50-conductor cable. A
 characteristic impedance of 100 ( 10%) ohms is recommended for un-
 shielded flat or twisted pair ribbon cable.

 A minimum conductor size of 28 AWG should be employed to minimize
 noise effects and ensure proper distribution of optional terminator
 power.

 A stub length of no more than 0.2 meters is allowed off the main-line
 interconnection within any connected equipment.

   a. Input Characteristics

      Each of the drive's signal receivers has the following
      characteristics when measured at the interface connector.

      I (input current on either input) =   2.0 milliamps, maximum

      Note: These characteristics include both receivers and passive
      drivers.

      This requirement is met with the input voltage varying between
      -7V and +12V, with power either on or off, and with hysteresis
       equaling 35 millivolts, minimum.

   b. Output Characteristics

      Each driven signal has the following characteristics when
      measured at the interface connector.

      VOL (low-level output voltage) = 1.7V maximum at IOL
           where IOL = 55 milliamps

      VOH (high-level output voltage) = 2.7V maximum at IOH
          where IOH = -55 milliamps

      VOD (differential voltage) = 1.0V minimum, with common-mode
          voltage ranges from -7 to +12

      VOL and VOH are measured between the output terminal and the
      SCSI device's logic ground reference.


   c. Terminator Power (TERMPWR at Pins 25 and 26)

      Terminator Power has the following requirements:

      V(TERM) = 4.0 VDC to 5.25 VDC

      600 milliamps minimum source drive capability, with 1.0 amp
      recommended current limiting (e.g., a fuse).

      1.0-milliamp maximum bus loading (except for the purposes of
      providing power to an internal terminator).

 The drive provides keyed connectors to prevent accidental
 grounding or misconnection of terminator power.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
MICROPL. 2112S/D/2108S/2105S  TECHNICAL MANUAL 135812 REV. A


 The single-ended and differential interface drive is compatible with
 the "ANSI CCS" and "SCSI-2" versions of the industry-standard Small
 Computer System Interface (SCSI) specification.


 Media Defects
 -------------
 Media defects are physical characteristics of the media which result
 in repetitive read errors when a functional drive is operated within
 specified operating conditions.

 At the time of manufacture, a media test system evaluates every
 drive and identifies each media defect location. The defective
 areas are identified by head address (HD), cylinder address (CYL),
 and number of bytes from Index (BFI).

 The list of manufacturer-found defects is stored on the drive in a
 reserved, write-protected area accessible by the SCSI controller.
 This list is known as the MDL (Manufacturers Defect List) or PList
 (Primary Defect List).

 A printed listing of the defects is also shipped with each drive. The
 entries it contains can be mapped out (reassigned) automatically at
 format time by appropriate format control parameter bits.


 Seek Time
 ---------

        ----------------------------------+--------+
        Track-to-Track  read   msec. typ. |   1.5  |
                        write  msec. typ. |   2.5  |
                       Average msec. typ. |  10    |
                               msec. max. |  25    |
        Latency                msec. avg. |   5.56 |
        ----------------------------------+--------+


 Preventive Maintenance
 ----------------------
 No preventive maintenance is required during normal use.


 Corrective Maintenance
 ----------------------
 There are no field-replaceable components within the sealed area;
 therefore, clean-area integrity MUST NOT be violated.

 The Micropolis warranty will be invalidated if any of the screws in
 the Head/Disk Assembly are removed.


 Field-Replaceable Parts
 -----------------------
 An ID is attached to the drive HDA casting. It indicates the model
 number, part number (Top Assembly number), and serial number of the
 drive. These numbers should be referenced when ordering the field-
 replaceable parts.

 Caution: DO NOT remove any of the screws securing the drive's top
 cover (Cover Assembly).


 Internal Data Rate
 ------------------
 24 to 40 MHz

 Sector Size = Variable; programmable up to 4096 bytes.


