MICROPOLIS 1598 DISK DRIVE 
                        SPECIFICATIONS 

                                       Model Number 
Unformatted Capacity:                   1598-15 

  Total Mbytes            --------------- 1203.0 ----------------
  Disk Platters           ------------------- 8 ----------------- 
  Read/Write Heads        ------------------ 15 -----------------
  Cylinders               ---------------  1928 -----------------
  Bytes per track         -------------- 41,664 -----------------

Formatted Capacity 

  Total Mbytes            --------------- 1034.6 ----------------
  Bytes per Sector        ----------------- 512 -----------------
  Sectors per Track       -----------------  71 -----------------

PC Setup 

  When using SCSI in a PC, the most common method is to run your 
  setup program and define No Drives Present. The SCSI Host Adapter
  will automatically self-configure on power-up. To install the  
  drive, follow the manufacturer's instructions to use the on-board
  BIOS routine or software that was supplied with the Host Adapter.

Performance Specifications 

  Seek Time                       Track-to-Track           4 msec 
    (including settling time)     Average               14.5 msec
                                  One-third Stroke(max) 15.5 msec
                                  Maximum                 33 msec
  Average Rotational Latency                            8.33 msec

  Rotational Speed                              3600 rpm +/- 0.5%

  Data Transfer Rate at Interface 
    Synchronous                                    5.0 Mbytes/sec
    Asynchronous                                   1.8 Mbytes/sec

  Internal Data Rate                                 20 Mbits/sec

  MTBF                                              150,000 hours

  Positioner                     Fully balanced rotary voice coil

  Parking                                 Automatic park and lock


General Functional Specifications 

  Interface                                                SCSI-2

  Supports Common Command Set                                 YES 
  Write Precompensation Start Cylinder                       1928 
  Reduced Write Current Start Cylinder                       1928
  Landing Zone                                               1928
  Mounting Plane                                  Any orientation

Power Requirements 
 
  +12V +/-5%                                            2.0 A Avg
                                      (4.35A max during start-up)
  +5V +/-5%                                              2.0A avg
  Power dissipation, typical                             30 Watts


7. Drive Addressing and Interface Termination 


              _ID2 
             |  _ID1 
             | |  _ID0 
             | | |                        Pin 1 
         J2  | | |              J1            |       J3  
      ___________    __________________________     ________ 
    _|           |  |                          |   |        | 
   | |___________|_ |__________________________|___|________| 
   |  ..  ..                                                | 
   |  W5  W4          RN9         W2                        | 
   |                              W1                 W11    | 
   |                                                        | 
   |                                                    W28 | 
   |                                                        | 
   |                                                        | 
   |                                                        | 
   |                                                        | 
   |                                                        | 
   |                                 Component Side         | 
   |                                                        | 


ID0, ID1, ID2 SCSI Address Jumpers 
  The SCSI ID (drive address) jumpers are identified as ID0, ID1,
  and ID2. ID selection is binary, as shown in the table below. 

   SCSI              Jumpers 
  Address        ID2   ID1   ID0 
  -------        ---   ---   --- 
     0           out   out   out 
     1           out   out    in 
     2           out    in   out 
     3           out    in    in 
     4            in   out   out 
     5            in   out    in 
     6            in    in   out 
     7            in    in    in 
 
  For multiple drive installations, on one Host Adapter, each drive
  must have a unique address. Drives are configured as SCSI ID 7
  at the factory. 

RN9 Interface Terminator 
  The Interface Terminator factory installed at RN9 provides    
  proper termination for the interface lines. When daisy-chaining 
  multiple drives, leave the terminator installed only in the last
  physical drive (or drives) on the daisy chain cable; remove the
  terminator from each of the other drives (or the host computer).

W1, W2, Terminator Option 
  W1 and W2 select the source of terminator power (+5V) for the  
  interface terminator. If a jumper is installed at W1(the factory
  default configuration), and no jumper is installed at W2 the  
  drive provides terminator power. This configuration is used    
  for PC/AT applications. If a jumper is on W2 the host adapter  
  will supply terminator power. If a jumper is installed at W2 and 
  W11, and no jumper is installed at W1 the drive provides       
  terminator power to it's on-board terminators and also to the  
  SCSI bus via interface connector J1, pin 26. 
 
W11 Bus Option 
  W11 allows the drive to supply interface terminator power to the
  SCSI Bus. If W11 is not installed and W1 is jumpered (the factory
  default configuration), the drive does supply SCSI bus interface 
  terminator power. W11 should not be installed for PC/AT        
  applications. 

W5 Spindle Option 
  Selects the spindle control option. If W5 is jumpered, the    
  drive must wait for a Start Spindle command (after power is    
  applied) to start the spindle motor. If W5 is not installed    
  (the factory default configuration), the drive automatically   
  starts the spindle motor at power-on. W5 is not installed for 
  PC/AT installations. 

W4 Bus Parity Option 
  W4 selects the parity check option. If W4 is installed, the drive
  neither generates nor detects parity. If W4 is not installed (the
  factory default configuration), the drive generates parity and
  enables parity detection. W4 is usually not installed for PC/AT
  applications. Verify the correct configuration required by your
  Host Adapter. 

W28 Ground Options 
  W28(only implemented on Rev B and later boards) is used to     
  connect the drive's logic ground to frame ground. When at jumper
  is installed at W28, frame ground is connected to logic ground.

  When a jumper is not installed at W28 (the factory default   
  configuration), frame ground is not connected to logic ground.
  For PC/AT applications, is a jumper should be installed at W28.