M 8 0 5 1 A   P 4    MINISCRIBE

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                                                      Native|  Translation
Form                 3.5"/HH               Cylinders     745|  981|     |
Capacity form/unform    41/   51 MB        Heads           4|    5|     |
Seek time   / track  28.0/ 8.0 ms          Sector/track   28|   17|     |
Controller           IDE / AT              Precompensation
Cache/Buffer            32 KB              Landing Zone
Data transfer rate    1.000 MB/S int       Bytes/Sector      512
                      4.000 MB/S ext
Recording method     RLL 2/7                        operating  | non-operating
Supply voltage     5/12 V       Temperature *C         4 50    |    -40 65
Power: sleep              W     Humidity     %         8 80    |      8 80
       standby            W     Altitude    km    -0.061  3.048|        12.192
       idle           8.0 W     Shock        g        10       |     80
       seek               W     Rotation   RPM      3484
       read/write         W     Acoustic   dBA        45
       spin-up            W     ECC        Bit
                                MTBF         h     150000
                                Warranty Month
Lift/Lock/Park     YES          Certificates     CSA,TUV                      

                        L   A   Y   O   U   T
MINISC.  8051A  PRODUCT MANUAL NO. 1136 REV. D 04/02/90

  |                                              1++++++J4  |XX
  |                                              2++++++    |XX
  |                                                         |XX J1
  |                                                   JP1+++|XX
  |                                                     ++++|XX
  |                                                      JP2|XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |XX
  |                                                         |
  |                                                         |XX Power
  |                                                         |XX J3

   MiniScribe AT Interface Board
  |         LED1xxx   39------------------------1           |
  |               +    |::::::::::::::::::::::::|           |
  |                   40------------------------2           |
  |       +++++++                 J1                        |
  |       +++++++                                           |
  |     JP1-----JP6                                         |
  |                                                         |
  |                                                         |
  |                                                         |
  |                                                         |
  |                                                         |
  |                                                         |
  |                                                         |
  |       P2C                        P1A                    |
  +--+                +-+                              +----+
     ++++++++++++++++++ +++++++++++++++++++++++-++++++++
     18               1 31                             1


                      J   U   M   P   E   R   S
MINISC.  8051A PRODUCT MANUAL NO. 1136 REV. D, 04/02/90

 Jumper Setting

 Dual Drive Support
 Two drives may be accessed via a common interface cable, using the
 same range of I/O addresses. The drives are jumpered as drive 0 or 1,
 and are selected by the drive select bit in the Drive/Head register
 of the task file.

 All Task File registers are written in parallel to both drives. The
 interface processor on each drive decides whether a command written
 should be executed, depending on the type of command and which drive
 is selected. The drive not selected does not execute the command and
 does not activate the data bus in response to host I/O reads.

 A master/slave relationship exists between the two drives: drive 0 is
 the master, and drive 1 the slave.

 In response to the Execute Diagnostics command, both drives execute
 diagnostics; the slave reports its status to the master via the
 -PDIAG line. The master then combines the slave's status with its own
 before reporting status to the host.

 Mode Jumpers
 Jumpering J4.1 to J4.2 causes the 8051A to operate in the slave role.
 Remove this jumper when the drive is to function as the master, or is
 the only drive attached.

 To emulate 2:1 interleave timing, jumper J4.3 to J4.4. This allows
 compatibility with some BIOS versions which cannot support 1:1 inter-
 leave transfers. For normal operation, remove this jumper.

 In a two drive system, jumper J4.5 to J4.6 when the drive is
 operating as the master. The jumper is not installed on a slave or
 single drive.

 Jumper J4.7 to J4.8 is not used, and should be not installed.

 Jumpering J4.9 to J4.10 enabled the I/O Channel Ready signal onto the
 interface connector, pin 27.

 The 0851A may be shipped with a jumper between J4.1 and J4.3. This
 jumper has no effect, but merely provides a spare for use as
 described above.

 Interface Board Jumper Configuration Table
 JP1 Address Select   REMOVED   - (Default) Normal Operation
                      INSTALLED - Secondary address 170 through
                      177,376 through 377 decoded (for systems having
                      this capability)

 JP2 I/O Channel      INSTALLED - (Default) Gates I/O Channel Ready to
     Ready            the system bus.

 JP3                  REMOVED   - (Default) Normal operation

 JP4                  INSTALLED - (Default) Normal operation

 JP5                  REMOVED   - (Default) Normal operation

 JP6 Active           INSTALLED - (Default) Normal operation
                      Enables activity LED on interface board.
                      REMOVED   - Disables interface board activity


                      I   N   S   T   A   L   L
MINISC.  8051A  PRODUCT MANUAL NO. 1136 REV. D, 04/02/90

 Notes On Installation

 Recommended Mounting Configuration
 The MiniScribe 8051A quarter size drive design allows greater shock
 tolerance than that afforded by larger, heavier drives.

 To take full advantage of the shock mounts, provide a minimum 0.1"
 clearance on both the top and sides of the drive. This clearance
 allows for drive movement during acceleration.

 The drive may be mounted in any attiude.

 Mount the drive using size 6-32 screws with 1/8" maximum penetration.

 Allow adequate ventilation to the drive to ensure reliable drive
 operation over the operating temperature range.

 Ground Terminal
 A Ground Terminal is provided in one of these locations. Attach
 ground wire (if provided with system) to the ground terminal during
 installation of the drive.

 Power Connector
 Power is applied through J3, a 4 pin AMP connector. The recommended
 mating connector is AMP P/N 1-480424-0, using pins AMP P/N 350078-4.

 /------------\ P3-1 = +12 Volts DC
 | 4  3  2  1 | P3-2 = +12 Volts Ground Return
 +------------+ P3-3 = + 5 Volts Ground Return
                P3-4 = + 5 Volts DC

 Interface Connector
 The integrated drive interfaces to the host computer via a 40
 position ribbon cable connector.


                      F   E   A   T   U   R   E  S
MINISC.  8051A  PRODUCT MANUAL NO. 1136 REV. D, 04/02/90

 The MiniScribe 8051A disk drive is a 41 megabyte (formatted),
 half-height 3.5" random access storage device with an integrated AT

 Proven microprocessor spin control and voice coil actuator ensure
 high performance and reliability. Superior mechanical construction
 and a sophisticated integrated PCB contribute to maintenance-free
 operation throughout the life of the device.

 A sealed enclosure houses heads, disks and actuator assemblies. The
 enclosure contains recirculating and breather-type filters which can
 supply clean air to the head and disk environment.

 The drive interfaces to an 80286 or 80386 AT-type system via the
 system's onboard 40 pin AT connector, or through a MiniScribe AT
 interface board.

 Auto Park and Head Lock
 Immediately following power down, dynamic braking of the spinning
 disks delays momentarily. This allows time for the heads to move into
 the landing zone - a safe area, away from stored data.

 The head actuator assembly then mechanically latches into position,
 and the disks spin down.

 Disk Caching
 A disk cache involves the temporary storage of information from the
 hard disk to the faster 32K RAM.

 Subsequent host requests for the same information are met more
 quickly by cache memory than by repeated, direct accesses to the hard

 Cache "hits" refer to information requests satisfied from cache
 memory. As cache memory accesses increase, system performance

 Drive Mechanism
 A brushless DC direct drive motor rotates the spindle at 3484 RPM.
 The dynamically balanced motor/spindle assembly ensures minimal
 mechanical runout to the disks. A dynamic brake provides a fast stop
 to the spindle motor upon power removal.

 Air Filtration System
 Over the life of the drive, a 0.3 micron filter and breather filter
 (located within the sealed enclosure) maintain a clean, above-
 atmospheric pressure environment to the heads and disks.

 MiniScribe AT Interface Boards
 To use the 8051A with an AT system that does not incorporate address
 decoding or buffering on its motherboard, you must use a MiniScribe
 AT interface oard. (Otherwise, simply interface via the system's on-
 board 40 pin AT connector.

 MiniScribe AT interface boards serve two primary functions:

 1. Buffer signals between host and drive
 2. Provide address decoding for the drive.


                      G   E   N   E   R   A   L

 1. Install a 40 pin Data Cable ensuring that pin 1, which can be
    identified by the striped edge of the cable, is closest to the
    power connector on the drive.

 2. Install a DC power cable to the back of the drive.

 3. Verify the jumper configurations for Master/Slave operation
    (Note:  Master will be the bootable drive. The slave will not
    be bootable.) Also make sure the existing C: drive is jumped
    to be the Master in a two drive system, not the only drive in
    the system.

 4. Apply power to the computer.

 4a. When memory test is complete go into your system's Standard
     CMOS set-up.
     (Note: There are various ways to get into CMOS set-up, please
     refer to system's manual for instructions.)

 4b. If your system's BIOS supports a user programmable drive
     type, program the BIOS with the default parameters of your
     drive. If your system does not support a user programmable
     drive type choose parameters that closely match but do not
     exceed the drives MegaByte capacity. Escape from set-up
     then choose write to CMOS and exit.

 5. Boot from a DOS diskette that has FDISK.EXE and FORMAT.COM on
    it. At the A> prompt type in FDISK. At the menu options select
    option 1 to create a DOS partition. Another menu will appear
    and from those options choose 1 to create a Primary DOS
    partition. Select yes to make 1 large partition and it will
    automatically become active. Then escape from FDISK.

 6. At the A> prompt type in FORMAT C:/S This does a high-level
    format on the drive and transfers the system files in order for
    the drive to be bootable. (Note: IDE drives are low-level
    formatted from the manufacturer and only need a high-level

    To configure the drive as a slave drive repeat steps 1-4 and
    proceed with steps 5a. and 6a. as follows:

  5a. At the C> prompt type in FDISK. When the menu options appear
      select option 5 to switch to the second drive. Enter fixed
      disk drive number 2. Then choose option 1 to create a DOS
      partition, then select option 1 again to create a Primary DOS
      partition or option 2 to create an Extended DOS partition.
      (Note: C and D drives will always be the Primary partitions
      but only the Primary partition on C: will have a status of

  6a. Proceed with a high-level format on the drive by typing FORMAT
      D: (Note: Make sure the correct drive letter has been selected
      for format).

 7. The drive is now bootable. As a test remove the DOS diskette
    from A and press reset to reboot the computer,  a  C> should be
    displayed, the drive is now ready for operation.