1 5 4 8 - 1 5    MICROPOLIS
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 5.25"/FH              Cylinders    2099|     |     |
Capacity form/unform  1748/ 2000 MB        Heads          15|     |     |
Seek time   / track  11.0/ 2.5 ms          Sector/track     |     |     |
Controller           SCSI2 SI/FAST         Precompensation
Cache/Buffer           256 KB DUAL-PORTED  Landing Zone
Data transfer rate    4.500 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        10 50    |    -40 65
Power: sleep              W     Humidity     %        10 90    |     10 90
       standby       18.0 W     Altitude    km    -0.061  3.048| -0.305 15.240
       idle               W     Shock        g         3       |     40
       seek               W     Rotation   RPM      3600
       read/write    24.0 W     Acoustic   dBA        40
       spin-up            W     ECC        Bit   64
                                MTBF         h     150000
                                Warranty Month        60
Lift/Lock/Park     YES          Certificates


**********************************************************************
                        L   A   Y   O   U   T
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MICROPL. 1548  PRODUCT DESCRIPTION 110682 REV. B

   Single-Ended
  +---------------------------------------------------------++-+
  |                                                         || 20  J2
  |                                                         || |
  |   COMPONENT SIDE                                        || |  ID2
  |                                                         || |  ID1
  |                                    W8 ++                |1-2  ID0
  |                                       ||         W12+++ |XX
  |                                    W9 ++            +++ |XX
  |                                                 RN6+-+  |XX
  |                                          Interface | |  |XX
  |                                          Terminator| |  |XX J1
  |                                                    | |  |XX
  |                                                    +-+  |XX
  |                                                   ++++  |XX
  |                                                   ++++  |XX
  |                                                  W2  W1 |  1
  |                             Frame Ground W11++          |XX J3
  |                                             ++          |XX Power
  +---------------------------------------------------------+  1






   Differential
  +---------------------------------------------------------++-+
  |                                                         || 20  J2
  |                                                         || |
  |   COMPONENT SIDE                                   +-+  || |  ID2
  |                                                 RN12 |  || |  ID1
  |                                    W8 ++           | |  |1-2  ID0
  |                                       ||           | |  |XX
  |                                    W9 ++           +-+  |XX
  |                                                 W2++++W1|XX
  |                                                   ++++  |XX
  |                                                W10+++   |XX J1
  |                                                   +++   |XX
  |                                                 RN11-+  |XX
  |                                                    | |  |XX
  |                                                    | |  |XX
  |                                                    | |  |  1
  |                             Frame Ground W11++     +-+  |XX J3
  |                                             ++          |XX Power
  +---------------------------------------------------------+  1





     +--------------------------------------+
     |         ++J4 HDA Ground Connector    |
     |         ++                           |
     |    ++J5 Frame Ground Connector       |
     |    ++                                |
     |                                      |
     |   J2    1        J1        1   J3   1|
     +..........-XXXXXXXXXXXXXXXXXX-XXXXXXXX+
     +-Multi-+++---Signal------------Power--+
             |||
             ||+--- SCSI ID0
             |+---- SCSI ID1
             +----- SCSI ID2



**********************************************************************
                      J   U   M   P   E   R   S
**********************************************************************
MICROPL. 1548  PRODUCT DESCRIPTION 110682 REV. B

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

 x = Jumpers setting at factory


 J2  Multi-Function Connector
 ----------------------------


     Write Protect Option----+     +---------Spindle Control Option
                             |     |  +------ID2
 Bus Parity Check Option--+  |     |  |  +---ID1
                          |  |     |  |  |   ID0
     --+  +--+--+--+--+--++-++-+--++-++-++-+-++ +-----
       +--+23|21|19|17|15|13|11|09|07|05|03|01+-+
       +--+24|22|20|18|16|14|12|10|08|06|04|02+-+  J1
     --+  +--+--+-++--++-+--+--+--+--+--+--+--+ +------
        Slave Sync+    Master
                       Sync

 Note: Pins 2, 4, 6, 8, 10, 12, and 14 are tied to Ground.


 J2  SCSI ID
 -----------
   +----------+-----------------------+
   | SCSI ID  |        Jumpers        |
   |          | ID2   | ID1   | ID0   |
   +----------+-------+-------+-------+
   |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|
   +----------+-------+-------+-------+

 Up to eight devices (the host and seven targets) can be attached to
 the SCSI bus. The 1548 drive has three ID jumpers. These three
 jumpers are used to assign one of the eigth SCSI ID bits (0 through
 7) to the drive.

 SCSI ID = 0; factory default configuration.

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

 Single-Ended
 Interface Terminator RN6 provides proper termination for the inter-
 face lines. For a multiple-drive system, the terminator is installed
 in the last drive on the cable.

 Differential
 Interface Terminator packs RN11 and RN12 provide proper termination
 for the interface lines. For a multiple-drive system, the terminators
 are installed in the last drive on the cable.


 J2  Spindle Control Option
 --------------------------
     Pin 7-8 CLOSED  The drive must wait for an interface START UNIT
                     command to start the spindle motor.
             OPEN    The drive automatically starts the spindle motor
                     at power-on. (Factory default configuration)


 J2  Write Protect Option
 ------------------------
     Pin 11-12 CLOSED  The drive is write protected. CAUTION: The
                       drive can still be formatted.
               OPEN    The drive is not write protected. (Factory
                       default configuration)


 J2  Bus Parity Check Option
 ---------------------------
     Pin 13-14 CLOSED  The drive neither generates nor detects parity.
               OPEN    The drive generates parity and enables parity
                       detection. (Factory default configuration)


 J4/J5  Ground Connectors
 ------------------------
 3/16-inch spade lugs J4 and J5 are provided for grounding.
 System characteristics determine proper ground connection.


 W1/W2/W12  Bus Termination Power Option (Single-Ended)
 ------------------------------------------------------

   +-----------------------+------------------------------------+
   |        Jumpers        |                                    |
   |  W1   |  W2   |  W12  |                                    |
   +-------+-------+-------+------------------------------------+
   | CLOSED| OPEN  | OPEN  |The drive provides terminator power |
   |       |       |       |to its on-board terminators         |
   |       |       |       |(Factory default configuration)     |
   +-------+-------+-------+------------------------------------+
   | OPEN  | CLOSED| OPEN  |Terminator power is provided by the |
   |       |       |       |host via interface cable J1, pin 26 |
   +-------+-------+-------+------------------------------------+
   | OPEN  | CLOSED| CLOSED|The drive provides terminator power |
   |       |       |       |to its on-board terminators and     |
   |       |       |       |also to the SCSI bus via interface  |
   |       |       |       |cable J1, pin 26 (TERMPWR)          |
   +-------+-------+-------+------------------------------------+

 A jumper is installed at W1, at W2, or at W2 and W12 to select the
 source of terminator power (+5V) for the SCSI bus terminator packs on
 the Device Electronics board.

 Do not install jumpers at both W1 and W12.



 W1/W2/W10  Bus Termination Power Option (Differential)
 ------------------------------------------------------

   +-----------------------+------------------------------------+
   |        Jumpers        |                                    |
   |  W1   |  W2   |  W10  |                                    |
   +-------+-------+-------+------------------------------------+
   | CLOSED| OPEN  | OPEN  |The drive provides terminator power |
   |       |       |       |to its on-board terminators         |
   |       |       |       |(Factory default configuration)     |
   +-------+-------+-------+------------------------------------+
   | OPEN  | CLOSED| OPEN  |Terminator power is provided by the |
   |       |       |       |host via interface cable J1, pin 26 |
   +-------+-------+-------+------------------------------------+
   | OPEN  | CLOSED| CLOSED|The drive provides terminator power |
   |       |       |       |to its on-board terminators and     |
   |       |       |       |also to the SCSI bus via interface  |
   |       |       |       |cable J1, pin 26 (TERMPWR)          |
   +-------+-------+-------+------------------------------------+

 A jumper is installed at W1, at W2, or at W2 and W10 to select the
 source of terminator power (+5V) for the SCSI bus terminator packs on
 the Device Electronics board.

 Do not install jumpers at both W1 and W10.


 W8/9  Spindle Synchronization Option
 ------------------------------------
 Jumpers installed (CLOSED) at W8 and W9 provide termination for the
 Spindle Synchronization signals (Slave Sync and Master Sync respect-
 ively).

 When the Spindle Synchronization option is to be implemented, the
 jumpers 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.

 The following options are supported:

 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 20) supplied by an external
 source.

 Master: If the drive is set to Master (RPL = 10b), it generates the
 SLAVE SYNC output signal (J2, pin 20) for use directly by the slave
 drives.

 Master Control: If the drive is set to Master Control (RPL = 11b), it
 generates the MASTER SYNC signal (J2, pin 16). This output is used by
 the controller to generate the SLAVE SYNC signal (J2, pin 20) for the
 slaves.


 W11  Frame Ground Option
 ------------------------
      W11  CLOSED  Frame ground is connected to logic ground
           OPEN    Frame ground is not connected to logic ground
                   (Factory default configuration)


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



**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
MICROPL. 1548  PRODUCT DESCRIPTION 110682 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


 Dimensions and Mounting
 -----------------------
 The 1548 drive uses industry-standard mounting techniques for 5 -inch
 full-height Winchester disk drives.

 Recommended orientation is vertical on either side, or horizontal
 with the Device Electronics board down; other mounting orientations
 may be used provided the ambient air temperature around the drive is
 kept at or below 50*C (122*F).

 The term "ambient" becomes imprecise when referencing a drive in a
 system, since it is difficult to determine where the air temperature
 should be measured. To help resolve this confusion, Micropolis
 specifies that the maximum HDA casting temperature (regardless of the
 air temperature around the drive) is 60*C (140*F). Not exceeding this
 temperature will ensure that the head-to-media interface never exceed
 its temperature limit.


 Mounting Screws
 ---------------
 2 per side 6-32 UNC-2B
 4 on bottom 6-32 UNC-2B

 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 mounting 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.


 SINGLE-ENDED Interface Electrical Characteristics
 -------------------------------------------------
 Interface control and status signals are digital (open collector TTL)
 using industry-standard transmitters and receivers which provide
 a terminated, single-ended system.

 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 three-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 cable. A
 characteristic impedance of 100 ( 10%) ohms is recommended for un-
 shielded flat or twisted pair ribbon cable.

   a. Input Characteristics

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

      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 1548 disk 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 drives 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 1548D drive provides keyed connectors to prevent accidental
 grounding or misconnection of terminator power.

 Interface Terminator packs RN11 and RN12 provide proper termination
 for the differential interface lines.


 Signal Connector J1
 -------------------
 J1 is a 50-pin connector. Signal interface connection is made via
 this connector. The signals on J1 include the 8-bit SCSI bus and
 various control and handshaking lines.

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


 J2 Multi-Function Connector/Jumper Block
 ----------------------------------------
 J2 is a 24-pin, multi-function connector/jumper block.


 J3  DC Power Connector
 ----------------------
 J3 is a 4-pin, keyed, AMP MATE-N-LOCK connector. Both +5V and +12V
 are supplied to the drive via this connector.

    Mating Connector:   AMP 1-480424-0 or equivalent
                Pins:   AMP 350078-4
 Suggested Wire Size:   18 AWG


 Ground Connectors J4 and J5
 ---------------------------
 3/16-inch spade lugs J4 and J5 are provided for grounding. Systems
 characteristics determine proper ground connection.

 Mating connector: AMP 60972-2 or equivalent.


 Multiple-Drive Systems
 ----------------------
 Up to seven 1548 drives can be connected to a single host.

                                             Drive #1
  +------HOST------+                 +-----------------+
  | +-----------+  +--+-SCSI-BUS-----+ J1              |
  | |Terminators|  |  |       +------+ J3   J4/J5      |
  | +-----------+  |  |       |      +--------+--------+
  |                |  |       |               +------------------+
  +----------------+  |       |              Drive #2            |
                      |       |      +-----------------+         |
                      +-------+------+ J1              |         |
                      |       o------+ J3   J4/J5      |         |
                      |       |      +--------+--------+         |
                      |       |               +------------------o
                      |       |              Drive #3            |
                      |       |      +-----------------+         |
                      +-------+------+ J1              |         |
                      |       o------+ J3   J4/J5      |         |
                      |       |      +--------+--------+         |
                      |       |               +------------------o
                      |       |              Drive #4            |
                      |       |      +--------------+--+         |
                      +-------+------+ J1           |T |         |
                              o------+ J3   J4/J5   +--+         |
           --DC-Voltages------+      +--------+--------+         |
           ---GROUND--------------------------o------------------+

 T = TERMINATORS

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

 Connectors J4 and J5 are provided for grounding; system character-
 istics determine the proper ground connection.


 Adjustments and Maintenance
 ---------------------------
 The 1548 drives requires no adjustments or periodic maintenance;
 additionally, no mechanical adjustments are required to prepare a
 system for handling or shipment.


 Field-Replacable Components
 ---------------------------
 The concept of repair by replacement of complete functional
 components is utilized in the 1548, resulting in an MTTR of less
 than 15 minutes.


 Air Filtration System
 ---------------------
 The 1548 drives are designed to provide contamination control within
 the sealed HDA throughout the life of the drive with zero
 maintenance.

 Air within the HDA is continuously recirculated and filtered through
 a high efficiency filter. Air is ducted to and from the filter for
 maximum pressure recovery and filter efficiency. Air within the HDA
 may only enter the drive through a high-efficiency breather filter.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
MICROPL. 1548  PRODUCT DESCRIPTION 110682 REV. B


 Micropolis 1548S (single-ended) and 1548D (differential) high-
 performance, 5 -inch full-height Rigid Disk Drives provide OEMs with
 random-access, high-speed data storage and meet the needs of diverse
 applications environment. These drivers are compatible with the
 "ANSI CCS" and "SCSI-2" versions of the industry-standard Small
 Computer System Interface (SCSI) specification.

 Throughout this Product Description the term "1548 drive" or "1548"
 refers to characteristics common to both the single-ended and
 differential drives.


 Some Features of the Drive
 --------------------------
 Programmable sector sizes from 180 to 4096 bytes in 1-byte in-
 crements.

 Automatic error recovery.

 Performance is enhanced by low SCSI command overhead. Intelligent
 features such as read-ahead and sophisticated buffer management make
 maximum use of the 256K dual-ported data buffer, which has full
 parity for data integrity.


 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 use of the format control parameter bits.


 Seek Time
 ---------

                                          | 1548   |
        ----------------------------------+--------+
                Adjacent Track msec.      |   2.5  |
        ----------------------------------+--------+
                       Average msec.      |  14    |
        ----------------------------------+--------+
                   Full Stroke msec.      |  29    |
        ----------------------------------+--------+
              One-Third Stroke msec. max. |  14.5  |
        ----------------------------------+--------+
        Latency                msec. avg. |   8.33 |
        ----------------------------------+--------+