
1 6 8 3 - 4    MICROPOLIS
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 5.25"/HH              Cylinders    1777|     |     |
Capacity form/unform   194/  222 MB        Heads           4|     |     |
Seek time   / track  14.0/ 4.0 ms          Sector/track   54|     |     |
Controller           SCSI1 SINGLE-ENDED    Precompensation
Cache/Buffer            64 KB DUAL-PORTED  Landing Zone
Data transfer rate    1.500 MB/S int       Bytes/Sector      512
                      4.000 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       13.6 W     Altitude    km    -0.061  3.048| -0.305 15.240
       idle               W     Shock        g         8       |     20
       seek          14.8 W     Rotation   RPM      3600
       read/write         W     Acoustic   dBA        42
       spin-up            W     ECC        Bit
                                MTBF         h      50000
                                Warranty Month
Lift/Lock/Park     YES          Certificates                                  

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MICROPL. 1680 SERIES  PRODUCT DESCRIPTION 106467 REV. A

  +---------------------------------------------------------+
  |                                                         |+-+ J2
  |                                      +---------+        ||X|
  | COMPONENT SIDE                       |SCSI     |        || | ID2
  |                                      |PROM U39 |        || | ID1
  |                                      +---------+        |+-1 ID0
  |                                                         |XX
  |                                             1-+   W31++ |XX J1
  |                                         RN9 | |      ++ |XX
  |                                   Terminator| |    W2++ |XX
  |                                             | |    W1|| |XX
  |                                             +-+      ++ |XX
  |                                                         |XX
  |                                                         |X1
  |                                                 W14 +-+ |
  |                                                 W3  | | |XX Power
  |                                                 W9  +-+ |XX J3
  +---------------------------------------------------------+  1







     +--------------------------------------+
     |         ++J4                         |
     |         ++                 ++J5      |
     |                            ++        |
     |                                      |
     |                                J3    |
     |   J2             J1          xxxxxxxx|
     +..........-XXXXXXXXXXXXXXXXXX-xxxxxxxx+
     +---------1------------------1--------1+
                                     Power



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                      J   U   M   P   E   R   S
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MICROPL. 1680 SERIES  PRODUCT DESCRIPTION 106467 REV. A

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

 x = Jumpers setting at factory


 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 1680 Series 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.


 J2  Multi-Function Connector/Jumper Block
 -----------------------------------------
 J2 is a 24-pin, multi-function connector/jumper block that is used
 for connecting the drive to a user-supplied Operator panel.

 J2 Pin 19  Logic ground

        20  Not used

        21  Write Protect Input. Logic ground disables writing and
            lights the Write Protect LED.

        22  Ready output. Logic ground indicates the drive is Ready
            and lights the Ready LED.

        23  +5V source for the LEDs.


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



 W1/W2/W31  Bus Termination Power Option
 ---------------------------------------

   +-----------------------+------------------------------------+
   |        Jumpers        |                                    |
   |  W1   |  W2   |  W31  |                                    |
   +-------+-------+-------+------------------------------------+
   | 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 W31 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 W31.



 W3  Spindle Control Option
 ---------------------------
     CLOSED  The drive must wait for a START UNIT command to start the
             spindle motor.
     OPEN    The drive automatically starts the spindle motor at
             power-on. (Factory default configuration)



 W9  Bus Parity Check Option
 ---------------------------
     CLOSED  The drive neither generates nor detects parity.
     OPEN    The drive generates parity and enables parity detection.
             (Factory default configuration)



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



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MICROPL. 1680 SERIES  PRODUCT DESCRIPTION 106467 REV. A

 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 1680 Series disk drives uses industry-standard mounting
 techniques for 5 -inch half-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).

 Inasmuch as the drive frame acts as a heat sink to dissipate heat
 from the unit, the enclosure and mounting structure should be
 designed to allow natural convection of heat around the HDA and
 frame. If the enclosure is small or natural convetion is limited,
 a fan may be required. In any case, no point on the HDA assembly
 should exceed 62*C (143*F).


 Mounting Screws
 ---------------
 4 per side 6-32 UNC-2B x 0.10 deep (thru hole).
 4 on bottom 6-32 UNC-2B x 0.22 deep

 Caution: To avoid restricting HDA sway space, the mounting screws
 must not penetrate the side mounting holes more than .10 (+.00,
 -.03) inch or the bottom mounting holes by more than .20 (+.00, -.03)
 inch. Torque applied to the screws must not exceed 8 in-lbs.


 Interface Electrical Characteristics
 ------------------------------------
 Interface control and status signals are digital (open collector TTL)
 utilizing 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) = 4.0 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 1680 series disk drive provides keyed connectors to prevent
 accidental grounding or misconnection of terminator power.


 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.


 J3  DC Power Connector
 ----------------------
 J3 is a 4-pin, keyed, AMP MATE-N-LOCK connector on the Motor Control
 board. Both +5V and +12V is 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.


 Interface Terminator
 --------------------
 Interface Terminator pack RN9 provides proper termination for the
 interface lines. For a multiple-device system, the terminator pack
 is installed in the LAST drive on the cable.


 Multiple-Drive Systems
 ----------------------
 Up to seven 1680 series disk drives can be connected to a single
 host. The figure shows the connections for a system configuration
 using four drives.

                                             Drive #1
  +------HOST------+                 +-----------------+
  | +-----------+  +--+-SCSI-BUS-----+ J1              |
  | |Terminators|  |  |       +------+ J3   J4/J5      |
  | +-----------+  |  |       |      +--------+--------+
  |                |  |       |               +------------------+
  +----------------+  |       |              Drive #2            |
                      |       |      +-----------------+         |
                      +-------+------+ J1              |         |
                      |       o------+ J3   J4/J5      |         |
                      |       |      +--------+--------+         |
                      |       |               +------------------+
                      |       |              Drive #3            |
                      |       |      +-----------------+         |
                      +-------+------+ J1              |         |
                      |       o------+ J3   J4/J5      |         |
                      |       |      +--------+--------+         |
                      |       |               +------------------+
                      |       |              Drive #4            |
                      |       |      +-----------------+         |
                      +-------+------+ J1          RN9 |         |
                              o------+ J3   J4/J5      |         |
           ---DC-VOLTAGES-----+      +--------+--------+         |
                                              |                  |
           ---GROUND--------------------------+------------------+

 Interface Terminator RN9 is 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 1680 series 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 1680 series, resulting in an MTTR of
 less than 15 minutes.


 Data Transfers
 --------------
 1680 series drives are capable of transferring data at 4.0 MB/s in
 SYNCHRONOUS mode and 1.6 MB/s in ASYNCHRONOUS mode.


 Read-Ahead
 ----------
 The read-ahead function causes the 1680 disk drive to transfer the
 requested block into its buffer and continue to read sequential
 blocks until the buffer (or segment) is filled or another command is
 received.

 On subsequent request for data, the buffer will be checked for the
 requested blocks. If the data already resides in the buffer, it will
 be transferred to the host and no media access will be necessary.
 This results in a significant improvement in performance.


 Data Buffer
 -----------
 The 64K data buffer may be divided into segments, with each segment
 holding data from a different area of this disk.

 Segmentation of the buffer maximizes the impact of read-ahead,
 especially in a multi-tasking or multi-user environment. By
 allocating a segment to each task or user, the chances of "cache
 hits" and enhanced performance are greatly increased.



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                      F   E   A   T   U   R   E  S
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MICROPL. 1680 SERIES  PRODUCT DESCRIPTION 106467 REV. A


 Frame
 -----
 The HDA is suspended within the cast outer frame on shock isolators/
 absorbers. This method of construction protects the HDA from
 mounting-related distortion or stress, and shock and vibration.


 Command Pre-Processing
 ----------------------
 Whenever possible, the 1680 Series prepares the next command for
 execution (received from another host) while the current command is
 executing. This feature takes advantage of any "dead" time, where the
 drive's microprocessor would otherwise be inactive, such as during a
 seek.

 Like the read-ahead function, command pre-processing is a time
 management technique that makes full use of the capabilities of the
 1680 series and enhances performance in multi-initiator systems.


 Seek Time
 ---------

                                          | 1680   |
        ----------------------------------+--------+
        Track-to-Track         msec. typ. |   4    |
                       Average msec. typ. |  14    |
                               msec. max  |  30    |
        One-Third Stroke       msec. max. |  15    |
        Latency                msec. avg. |   8.33 |
                 Nominal       msec. max. |  16.67 |
        ----------------------------------+--------+


 Defect Management
 -----------------
 The 1680 series has two techniques available for defect management:
 track-oriented and cylinder-oriented.


 Disk/Spindle Assembly
 ---------------------
 Up to four magnetic disks (depending on the model) are mounted on the
 spindle assembly, which includes a threephase brushless DC motor
 (commutated by three Hall-effect sensors). The casting supports each
 end of the spindle.


 Interface
 ---------
 The 1680 series is fully compatible with the Small Computer System
 Interface (SCSI) proposed by the American National Standards
 Committee.


 Formatted Capacity Calculation
 ------------------------------
 The formatted capacity of the 1680 series depends upon a number of
 user-selectable variables. One very critical variable is sparing,
 either track-oriented or cylinder-oriented.

 The following formula is used to calculate the formatted capacity (C)
 of the 1680 Series using cylinder-oriented sparing:

 C = [(SPT x HDS) - (SPARE_SPC)] x (1780 - 3 - SPARE_CYL x (BYTES)

 HDS is the number of data heads.

 SPARC SPC is the number of spare sectors per cylinder. This variable
 is user programmable. The recommended value varies with each drive
 model as follows:

 1684-7 = 4
 1684-6 = 3
 1683-5 = 3
 1683-4 = 2

 1780 is the number of physical cylinders.

 3 cylinders are used by the drive and are not user accessible.

 SPARE CYL is the number of spare cylinders. This variable is user
 programmable; a typical value for sparing is 3.

 BYTES is the bytes per sector (e.g., 1024, 512, etc.).


