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Hard Drive: PRIAM: V185R 108MB 5.25"/FH RLL ST506

V 1 8 5 R    PRIAM
NO MORE PRODUCED                                      Native|  Translation
Form                 5.25"/FH              Cylinders    1166|     |     |
Capacity form/unform   108/      MB        Heads           7|     |     |
Seek time   / track  30.0/ 5.0 ms          Sector/track   17|     |     |
Controller           RLL / ST506           Precompensation 65535
Cache/Buffer               KB              Landing Zone
Data transfer rate    0.938 MB/S int       Bytes/Sector      512
                      0.938 MB/S ext
Recording method     RLL                            operating  | non-operating
Supply voltage     5/12 V       Temperature *C         4 50    |    -40 60
Power: sleep              W     Humidity     %         8 80    |      5 95
       standby            W     Altitude    km    -0.305  3.000| -0.305 12.000
       idle               W     Shock        g         2       |     20
       seek               W     Rotation   RPM      3600
       read/write    27.0 W     Acoustic   dBA        50
       spin-up            W     ECC        Bit
                                MTBF         h      20000
                                Warranty Month
Lift/Lock/Park     YES          Certificates                                  



  |                                     J4--+  +-----------+/Outermost
  | Second PCB                           +--+  |           | board
  |                                            XXX Power   |
  |                                            XXX         |
  |                                            |           |XX
  |                                            |           |XX J1
  |                                            |           |XX
  |                                            | +-J6--+   |XX
  |                                            | +-----+   |XX
  |                                            |           |
  |                                            |     +-+   |XX
  |                                            |   J12 |   |XX
  |                                            |     | |   |XX J2
  |                                            |     +-+   |XX
  |                                            +-----------+



Jumper setting

x = Jumpers set at factory

J1/P1 Connector Pin Assignment

    |Ground Return  Signal      Signal Name     Terminated?  |
    |Pin Number     Pin Number                               |
    |    1              2       -Not Used           Yes      |
    |    3              4       -Head Select 2      Yes      |
    |    5              6       -Write Gate         Yes      |
    |    7              8       -Seek Complete      No       |
    |    9             10       -Track 0            No       |
    |   11             12       -Write Fault        No       |
    |   13             14       -Head Select 2*     Yes      |
    |   15             16       Reserved (J2 Pin 7) No       |
    |   17             18       -Head Select 2      Yes      |
    |   19             20       -Index              No       |
    |   21             22       -Ready              No       |
    |   23             24       -Step               Yes      |
    |   25             26       -Drive Select 1     Yes      |
    |   27             28       -Drive Select 2     Yes      |
    |   29             30       -Drive Select 3     Yes      |
    |   31             32       -Drive Select 4     Yes      |
    |   33             34       -Direction In       Yes      |
 Note: The Terminations on J1 signals  can be removed by removing the
 Resistor Pack from its socket on the Data (outside) board.

All odd pins are ground. A key slot is between pins 4 and 6.

J2/P2 Connector Pin Assignment

    |Ground Return   Signal       Signal Name                |
    |Pin Number      Pin Number                              |
    |    2              1         -Drive Selected            |
    |    4              3         Reserved                   |
    |    6              5         Spare                      |
    |    8              7         Reserved (to J1 pin 16)    |
    |                   9         Spare                      |
    |                  10         Spare                      |
    |   12             11         GND                        |
    |                  13         +MFM Write Data *          |
    |                  14         -MFM Write Data *          |
    |   16             15         GND                        |
    |                  17         +MFM Read Data             |
    |                  18         -MFM Read Data             |
    |   20             19         GND                        |
    * Permanently Terminated

A key slot is provided between pins 4 and 6.

 J3/P3  DC Connector Pin Assignments
     | 4 3 2 1 |  J3 Connector Inner PCB Solder Side
       Pin 1      +12 Volts DC
       Pin 2      +12 Volts Return
       Pin 3      + 5 Volts Return
       Pin 4      + 5 Volts DC

J6 Drive Select
Two options are implemented via J6 on the outer printed circuit
board near connector J1. These options are selected by means of a
shunt block or dipswitch on early models, or by pins with a moveable
jumper on current models.

    |Drive Select| Cut Shunts           |OR|  Shorting Plugs|
    |     DS1    | 10-7, 11-6, and 12-5 |OR|   Short  9-8   |
    |     DS2    |  9-8, 11-6, and 12-5 |OR|   Short 10-7   |
    |     DS3    |  9-8, 10-7, and 12-5 |OR|   Short 11-6   |
    |     DS4    |  9-8, 10-7, and 11-6 |OR|   Short 12-5   |
    DRIVE SELECT, when  low level, connects the drive interface to the
    control lines. Cuting the appropriate shunts at IC position will
    determine which select line on the interface will activate that
    drive. The table indicates which DRIVE SELECT shunts must be cut.

A status line is provided at the J2/P2 connector to inform the host
system of the selection status of the drive.

The DRIVE SELECTED line is driven by a TTL open collector driver.
This signal will go active when the proper DRIVE SELECT line is
active. The DRIVE SELECT X line at J1/P1 is activated by the host

Drive Select jumpers on the shunt block are all shorted when shipped.
Dipswitches and pins will have only Drive Select 1 selected. Outputs
are not active until the drive is selected. Pin groups 1-16, 5-12,
6-11, 7-10, and 8-9 control the Drive Select function. The function
desired is left shorted; the others must be opened.

 J6   Radial
 x  Radial         1-16    OPEN

 J6  Auto Access (for factory use)
 x  Auto Access   2-15    OPEN
                          CLOSED  The drive will perform a repeating
                                  series of predetermined seek oper-
                                  ations with no signals required on
                                  the interface upon power up. This
                                  is normally used in the Priam
                                  factory to provide dynamic exercise
                                  of the during manufacturing burn-in.

Auto Access is also referred to as "Self Test"

The following additional options are implemented by pads (J12) on the
Data PCB near interface connector J2.

       Power Sequencing
       Non-Multiplexed Index
       Write Protect
       Radial Seek Complete

 J12  Power Sequencing (PS)
 A trace pad (J12-1) is aviable which, when shorted to DC ground, will
 inhibit starting of the DC spin motor, even if DC voltages are
 applied. When not connected to ground, the drive will sequence up
 normally. This can be used in multiple drive installations to mini-
 mize in-rush motor start currents on the +12V line. The function can
 be implemented by connection of an external wire, or bridging the
 trace to one of the unused pins on the interface connectors. Ground
 connections are available at J12.

J12 Non-Multiplexed Index (NMI)
This trace pad (J12-5) can be connected on the J2 interface to
provide an Index signal even when the drive is not selected. This
signal is not driven by a line driver and may not meet cable length

J12 Write Protect (WP)
A pad (J12-13) is available which can be used to inhibit write opera-
tions on the drive when shorted to DC ground. If desired, an external
switch can be connected to the pad, providing a manual write protect
function. Ground connections are available at J12.

J12 Radial Seek Complete (SC)
This trace pad (J12-8) can be connected to a spare pin on the J2
interface to provide a seek complete signal even if the drive is not
selected. This is useful in some applications to enhance multiple
seek overlap functions. This signal is not driven by a line driver
and may not meet cable length specifications.



Notes on installation

Installation direction

     horizontally                           vertically
   +-----------------+             +--+                       +--+
   |                 |             |  +-----+           +-----+  |
   |                 |             |  |     |           |     |  |
 +-+-----------------+-+           |  |     |           |     |  |
 +---------------------+           |  |     |           |     |  |
                                   |  |     |           |     |  |
      x           x                |  |     |           |     |  |
 +------x------x-------+           |  +-----+           +-----+  |
 +-+------x--x-------+-+           +--+                       +--+
   |       xx        |
   |     x    x      |
     x            x

Recommended orientation is either vertical on either side or
horizontal with PCB down. In the final mounting configuration, ensure
that operation of the four shock mounts is not inhibited.

Shipping Damage Inspection
Priam disk drives are packaged to withstand normal handling in
reusable shipping containers. It is the customer's responsibility to
notify the carrier if shipping damage should occur to a drive.

Note: When handling the drive while still in the shipping container,
ensure that the container remains in the upright position indicated
by the attached labels.

Do not place drives in vertical positions closer than 2 to 3 inches
apart to avoid hitting and breaking components.

Shock and Vibration Precautions
The drives must be handled in such a manner as not to exceed the Non-
Operational Shock and Vibration limits.

Mounting Holes
Eight mounting holes, four on the bottom and two on each side, are
provided for mounting the drive in an enclosure. The size and
location of these holes, are identical to the industry standard mini-
floppy drive.

Drive Connection

                  Typical Connection 4-Drive System
   +-----------+                                +-----------------+
   |           +---o----------------------------+J1      Drive #1 |
   |           |   |    +----DATA---------------+J2               |
   |           |   |    |             +---------+J3  J4           |
   |           |   |    |             |         +-----+-----------+
   |           |   |    |             |   +-----------+
   |           |   |    |             |   |     +-----------------+
   |Controller |   o----+-------------+---+-----+J1      Drive #2 |
   |           |   |    | +--DATA-----+---+-----+J2               |
   |           |   |    | |           o---+-----+J3  J4           |
   |           |   |    | |           |   |     +-----+-----------+
   |           |   |    | |           |   o-----------+
   |           |   |    | |           |   |     +-----------------+
   +-----------+   o----+-+-----------+---+-----+J1      Drive #3 |
   +-----------+   |    | | +---------+---+-----+J2               |
   |           +---+----+ | |         o---+-----+J3   J4          |
   |           +---+------+ |         |   |     +-----+-----------+
   |           |   |        |         |   o-----------+
   |Data       +---+--DATA--+         |   |     +-----------------+
   |Separator  |   +------------------+---+-----+J1      Drive #4 |
   |           +------DATA------------+---+-----+J2               |
   |           |                      o---+-----+J3   J4          |
   +-----------+                      |   |     +-----+-----------+
                                      |   o-----------+
                  DC Voltages---------+   |
                  (Radial)                |
                  Frame Ground------------+

Note: Termination resistor pack to be installed only in the last
physical drive on line.

J1/P1 Connector - Control Signals
Connection of J1 is through a 34-pin edge connector. The pins are
numbered 1 through 34 with the even pins located on the component
side of the PCB. Pin 2 is labeled. The recommended mating connector
for P1 is AMP ribbon connector P/N 88373-3 or Molex 15-35-1341. All
odd pins are ground.

J2/P2 Connector - Data Signals
Connection to J2 is through a 20-pin edge connector. The pins are
numbered 1 through 20 with the even pins located on the component
side of the PCB. The recommended mating connector for P2 is AMP
ribbon connector P/N 88373-6, or Molex P/N 15-35-1201. Pin 2 is

J3/P3 Connector - Power
DC power connector (J3) is a 4-pin AMP Mate-N-Lok connector P/N
350211-1 mounted on the solder side of the PCB. The recommended
mating connector (P3) is AMP P/N 1-480424-0 utilizing AMP pins P/N
350078-4 (Strip) or P/N 61173-4 (Loose piece).

J4/P4 Frame Ground Connector
Faston AMP P/N 691761-2
Recommended mating connector AMP 62187-1
If used, the hole in J4 will accomodate a wire of size 18AWG max.

Data Transfer Lines
All lines associated with the transfer of data between the drive and
the host system are differential in nature and may not be multi-
plexed. These lines are provided at the J2/P2 connectors on all

Two pairs of balanced signals are used for the transfer of data:

Flat ribbon or twisted pair
Maximum 20 feet
Note: Any EIA RS 422 Driver/Receiver pair will interface.

The faceplate is for cosmetic purposes only, serving no structural
requirement, and can be easily removed. Remove the four screw
adjacent to the side frames and disconnect the light emitting diode.
The recommended mating plug for J7 is AMP P/N 640442-2.

As shipped, the printed circuit board DC logic ground is connected to
the drive frame through the Head/Disk Assembly by a shorting plug
installed in location J12, connecting pin 15 with pin 16. In some
installations, disconnecting the PCB logic ground from the side frame
may give better results, depending on overall system grounding and
noise level.



General Operation
The V100 Series drives consist of read/write, head positioning and
control electronics, rotary voice coil actuator, media, air
filtration system, and disk spin motor.

These components perform the following functions:
1. Interpret and generate control signals.

2. Position and maintain the heads over the desired track.

3. Maintain precice disk rotation speed.

4. Read and write data.

5. Provide a contamination-free environment.

Read/Write, Servo and Control Electronics
Electronics are packaged on two printed circuit boards. The outer-
most board, to which control and data signals are connected,

1. R/W circuits

2. Interface drivers/receivers

3. Microprocessor and associated logic

4. Write fault detection

5. Drive selection

6. Optional interface functions

7. Index circuit

The second PCB, mounted under the top board, accepts the required DC
voltages and performs the following functions:

1. Disk spin motor control

2. Head actuator positioning

3. Tack 0 detection

4. -10 voltage regulator

5. Power monitoring

Disk Defects
Disk defects are imperfections in the media surface. No unit will be
shipped if surface analysis identifies more than 30, 50, 70, or 85
total defective tracks/drive for V130, V150, V170, and V185
respectively. Note that even at these maximum values, only 1% of the
drive capacity is unavailable. Additionally, no defects will be
present on cylinder 0, heads 0, 1, and 2.

Testing for defects invilves an analysis of the total media surface
under marginalized test conditions. Defect information is included on
the test data sheet shipped with the drive, and on the error map
label affixed to the drive. Format is cylinder number, head number
and bytes from index. Location accuracy is 10 bytes.

In a single format operation, it is probable that errors will not be
detected on all on the locations defined. However, all should be
considered defects and flagged by the using system to ensure long
term data reliability.

The use of an error correction code (ECC) rather than cyclic re-
dundancy check (CRC) is recommended for best data integrity.

Recording Method
All models support the use of 2.7 RLL encoding in addition to MFM.
When used with a controller utilizing RLL encoding, drive capacity
may be expected to increase up to 50% over the values stated above.
Note that error rate criteria may vary depending upon the type of
RLL encoding scheme used.

Seek Times

       |Physical track to track      max. |   5 ms |
       |               Average msec. typ. |  30    |
       |               Average msec. max. |  60    |
       |Latency                msec. avg. |   8.33 |
       Including settling and transmission of step pulses

Drive Mechanism
A brushless 3 phase DC drive motor rotates the spindle disk assembly
at 3600 rpm. The spindle is driven directly with no belt or pulley
beeing used. A crystal controlled phase lock loop maintains precise
speed regulation. The motor and spindle are dynamically balanced to
ensure a low vibration level. Dynamic braking is used to quickly stop
the motor when power is removed. The base plate assembly is shock
mounted to the side mounting frames to minimize transmission of
vibration through the chassis or frame. Index signal is derived from
a transducer inside the drive motor.

Air Filtration System
The disks, read/write heads and actuator are fully enclosed in a
module using an intergral recirculation air system and absolute
filter to maintain a clean environment. A separate filter permits
ambient pressure equalization without entry of contaminants.

Positioning Mechanism
The read/write heads and servo head are mounted onto a rotary
actuator supported by precision ball bearings. A bobbin-type voice
coil mounted between two permanent magnets provides the driving force
required to rotate the actuator for head positioning. Chrash stops
are provided to protect the head assemblies should a malfunction
cause the actuator to lose control. When the drive is powered down,
the actuator is driven to a head landing zone on the inner diameter
of the disk. Simultaneously, the actuator is automatically locked
over the landing zone to prevent possible head/media damage when the
drive is subjected to transport shock or movement around the office.

Automatic Head Actuator Lock
This automatic lock requires no action by the user. When the drive is
powered down, the actuator is automatically locked to prevent
possible head/media damage when shipping and handling the drive.

Drive Selection
Drive selection occurs when one of the DRIVE SELECT lines is
activated. Only the selected drive will respond to the input signals,
and only that drive's output signals are then gated to the controller

Recording Media
The recording media consists of a carbon overcoated thin film metal
magnetic coating on either side of a 130-millimeter (5.12 inch)
diameter aluminium substrate. In the V100 Series, there are several
such disks in the sealed head-disk assembly, with up to seven
surfaces used for data and one surface used for prerecorded servo in-

Input Buffers
The ST412/506 Interface control signals from the controller are input
to the microprocessor and the PLA via schmitt trigger input buffers.

Output Drivers
The ST415/506 control signals from disk drive are output via open-
collector drivers. Each driver is capable of sinking a maximum of 48
milliamperes at its low level (true state) with a maximum of 0.4
measured at the driver. When the driver is in its high level (false
state), the driver transistor is off. The output control signals are
gated by a Drive Select line developed from the Drive Select input

Control Input Lines
The control input signals are of two types: those to be multiplexed
in a multiple drive system, and those intended to do the
multiplexing. The control input signals to be multiplexed are WRITE
GATE, HEAD SELECT, STEP and DIRECTION IN. The signal to do multi-

The input lines have the following electrical specifications:

        TRUE  0.0 VDC to 0.4 VDC @ 1 = 48mA (max.), Active, Logic 1
        FALSE 2.5 VDC to 5.25 VDC @ 1 = +250 A (OPEN COLLECTOR),
                                        Inactive, Logic 0

Write Gate
The active state of this signal, or low lwvel, enables write data to
be written on the disk. The inactive state of this signal, or high
level, enables data to be transferred from the drive.

Control Output Lines
The output control signals are driven with an open collector output
stage capable of sinking a maximum of 48mA at low level or true state
with maximum voltages of 0.4V measured at the driver. When the line
driver is in the high level or false state, the driver transistor is
off and the collector leakage current is a maximum of 250 A.

All J1 output lines are enabled by their respective DRIVE SELECT

Reliability Specifications
Mean-time-between-failures (MTBF) More than 20,000 power on hours
Mean-time-to-repair (MTTR) less than 30 minutes
Component life 5 years

Shipping Requirement
The actuator is automatically locked whenever the drive is powered
down. When shipped as a single unit, the original shipping container
should be used. The container is designed to ensure no drive damage
will occur if the container is dropped from a height of 42" or less.

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