
W R E N   V I I F H   9 4 6 0 1 - 1 2 G    CDC
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 5.25"/FH              Cylinders    1931|     |     |
Capacity form/unform  1050/ 1201 MB        Heads          15|     |     |
Seek time   / track  15.0/ 2.5 ms          Sector/track     |     |     |
Controller           SCSI2 SINGLE-ENDED    Precompensation
Cache/Buffer           256 KB              Landing Zone
Data transfer rate    2.875 MB/S int       Bytes/Sector      512
                      4.800 MB/S ext SYNC
Recording method     RLL 1/7                        operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C        10 50    |    -40 70
Power: sleep              W     Humidity     %         8 80    |      5 95
       standby            W     Altitude    km    -0.305  3.048| -0.305 12.210
       idle          24.0 W     Shock        g         2       |     32
       seek               W     Rotation   RPM      3600
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit   48
                                MTBF         h     150000
                                Warranty Month
Lift/Lock/Park     YES          Certificates     CSA,SDA,FCC,IEC950,UL1950,...



**********************************************************************
                        L   A   Y   O   U   T
**********************************************************************
SEAGATE  ST41200N/ND  PRODUCT MANUAL 77765374-D (1/92)

  +---------------------------------------------------------+
  | +-+                                                     |+-1
  | | | J6                                                  || |J4
  | +-+                                                     |+-+
  |                                                     ++  |XX
  |                                                     ||  |XX
  |                                                     ||  |XX
  |                                     Terminator      +1  |XX J3
  |                                     resistor        ++  |XX SCSI
  |                                     (SIPs)          ||  |XX I/O
  |                                                     ||  |XX
  |                                                     +1  |XX
  |                                                     ++  |XX
  |                                                     ||  |XX
  |                                                     ||  |X1
  |                                                     +1  |
  | +-+J7                                                   |XX Power
  | +-+ LED                                                 |XX
  +---------------------------------------------------------+  1



**********************************************************************
                      J   U   M   P   E   R   S
**********************************************************************
SEAGATE  ST41200N/ND  PRODUCT MANUAL 77765374-D  (1/92)

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


  J4  SCSI ID/Option Select Header
  --------------------------------
           +------------------------+
           | o  o  o  o  o  o  o  o |
           | 1  o  o  o  o  o  o  o |
           +------------------------+
            TP TP  4  2  1 (2) (3) (6)
              (4)

      +------------+----------+
      |            | 4  2  1  |
      +------------+----------+  Drive ID in binary coded jumper
      |SCSI ID = 0 | o  o  o  |  position (most significant bit on
      |            | o  o  o  |  left), i.e., jumper in position 1
      +------------+----------+  would be Drive ID 1, no jumpers means
      |SCSI ID = 1 | o  o  x  |  ID 0.
      |            | o  o  X  |
      +------------+----------+
      |SCSI ID = 2 | o  x  o  |
      |            | o  X  o  |
      +------------+----------+
      |SCSI ID = 3 | o  x  x  |
      |            | o  X  X  |
      +------------+----------+
      |SCSI ID = 4 | x  o  o  |
      |            | X  o  o  |
      +------------+----------+
      |SCSI ID = 5 | x  o  x  |
      |            | X  o  X  |
      +------------+----------+
      |SCSI ID = 6 | x  x  o  |
      |            | X  X  o  |
      +------------+----------+
      |SCSI ID = 7 | x  x  x  |
      |            | X  X  X  |
      +------------+----------+

 (2)  CLOSED  Enables the Motor Start Option. In this mode of
              operation the drive will wait for a Start Unit Command
              from the Host before starting the Motor.
      OPEN    see Note (6) below for description of delayed motor
              start feature.

 (3)  CLOSED  Parity checking by the WREN 7 is enabled.

 (4)  If the unit is not be terminated, remove terminator resistor
      module SIPs. TP Jumper in left vertical position means
      terminator power (+5V) is from WREN 7 power connector. Jumper
      in horizontal position means terminator power is taken from
      interface cable. Jumper in right TP position means +5V is
      supplied to the interface cable pin 26. Jumpers can be in both
      vertical positions at same time. If the drive is not terminated,
      the TP jumper need not be installed.

 (6)  Jumper on enables delayed motor start (Motor Start jumper (2)
      must be off). Motor start up is delayed 16 times drive ID number
      in seconds; i.e., Drive 0 starts immediately, Drive 1 starts 16
      seconds later, Drive 2 starts 16 seconds after Drive 1, etc.


 J6  Write Protect/Remote LED Header
 -----------------------------------
                +------- GND              Pin 1 (+5V)
           +----+----+                    Pin 2 LED ON/OFF signal
           | 2  o  x +---- Reserved
           | 1  o  x +---- Reserved
           +----+----+
                +------- Write Protect

 The Write Protect/Remote LED Header is a 6-pin, 3 jumper (or
 connector) position header behind the front panel at the right side
 of the drive, opposite the LED. The pins are on 0.100 inch (2.54 mm)
 centers both vertically and side to side. A suggested mating two pin
 connector is the DuPont Mini Latch housing P/N 65291-008 or
 equivalent. The drive front panel must not be present in order to
 access the header. For a remote LED capability, plug the remote LED
 cable connector vertically to the leftmost two pins of the header.
 The center two pins provide a drive write protect capability. A
 shorting jumper plug may be plugged vertically onto these two pins to
 write protect the drive or a two-pin cable connector may be plugged
 there to connect the two pins to a remote Write Protect switch. The
 rigthmost two pins are RESERVED for factory use only.


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

 Note: Pins on the drive select and configuration select header are
 provided to facilitate manual drive configuration. No devices other
 than jumpers should be connected to these pins. Improper connection
 to external devices (switches, connectors, etc.) could adversely
 affect drive performance. Exact location of these pins and headers
 may change without notice.



**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
SEAGATE  ST41200N/ND  PRODUCT MANUAL 77765374-D (1/92)

 Notes on installation
 =====================

 Drive Orientation
 -----------------
 The balanced rotary arm actuator design of the WREN 7 allows it to
 be mounted in any orientation. All drive performance characterization
 however, has been done with the drive in horizontal (disc level) and
 vertical (drive on its side) orientations, and these are the two
 preferred mounting orientations.

 The WREN 7 is designed, manufactured, and tested with a "Plug-in and
 Play" installation philosophy. This philosophy minimizes the
 requirements for highly trained personnel to integrate the WREN 7
 into the OEM's system, wether in a factory or field environment.


 Mounting Holes
 --------------
 Four on bottom. Two on each side. 6-32-INC. max. screw length into
 side of chassis 3.17 mm (0.125 in). Max. screw length into bottom of
 chassis is 3.17 mm (0.125 in).


 Cooling
 -------
 Cabinet cooling must be designed by the customer so that the
 ambient temperature immediately surrounding the WREN 7 will not
 exceed temperature conditions. Specific consideration should be given
 to make sure adequate air circulation is present around the PWAs.


 Service Tools
 -------------
 No special tools are required for site installation or recommended
 for site maintenance. The depot repair philosophy of the WREN 7
 precludes the necessity for special tools. Field repair of the drive
 is not practical since there are no user purchasable parts in the
 drive.


 Air Cleanliness
 ---------------
 The WREN 7 is designed to operate in a typical office environment
 with minimal environment control.


 Drive Termination
 -----------------
 This option may be incorporated during manufacture at the request of
 the customer. For single ended interface drives, termination consists
 of three 220/330 ohm resistor modules (SIPs) which are installed on
 the Main PWA via sockets.


 Power Sequencing
 ----------------
 Power sequencing is not required for the WREN 7. The WREN 7 protects
 against inadvertent writing during power up and down. Daisychain
 operation requires that power be maintained on the terminated WREN 7
 to ensure proper termination of the peripheral I/O cables.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
SEAGATE  ST41200N/ND  PRODUCT MANUAL 77765374-D (1/92)

 Standards
 ---------
 The ST41200N/ND has been developed as a system peripherals to the
 highest standards of design and construction. The ST41200N/ND depends
 upon its host equipment to provide adequate power and environment in
 order to achieve optimum performance and compliance with applicable
 industry and governmental regualations. Special attention must be
 given in the areas of safety, power distribution, shielding, audible
 noise control, and temperature regulation.


 The ST41200N/ND is a UL Recognized component per UL478 or UL1950,CSA
 C22.2, No. 220-M1986 or CAN/CSA-C22.2 No. 950-M89, DIN VDE 0805/08.90
 and EN60950:1988 (IEC 950).

 The ST41200N/ND, as delivered, is designed for system integration
 before use. It is supplied as a component or subassembly as defined
 in the FCC Rules and Regulations, Part 15, Subpart J governing EMI
 of computing devices end the Radio Interference Regulations of the
 Canadian Department of Communications. The ST41200N/ND is, therefore,
 not directly subject to the FCC rules and regulations or the Radio
 Interference Regulations of the Canadian Department of
 Communications.


 The head, disc and actuator chamber (HDA) is environmentally sealed
 at the factory. Air is recirculated within the HDA and passes through
 a nonreplaceable filter to ensure the maintenance of a contamination
 free disc/actuator environment.

 The WREN 7 uses a dedicated landing zone at the innermost radius of
 the media thus eliminating the possibility of destroying or degrading
 data by landing in the data zone. The drive automatically disengaged
 when power is applied to the drive.

 The WREN 7 incorporates an automatic shipping look which prevents
 potential damage to the heads and discs caused by movements during
 shipping and handling. The shipping lock is automatically disengaged
 when power is applied to the drive.

 The WREN 7 decode Track 0 location from the dedicated servo surface
 thereby eliminating mechanical transducer adjustments and related
 reliability concerns.

 The WREN 7 use a high performance actuator assembly consisting of a
 low inertia, balanced, patented, straight arm design which provides
 excellent performance with minimum power dissipation.


 Media Description
 -----------------
 The media used in the WREN 7 has a diameter of approximately 5
 inches (130 mm). The aluminum substrate is coated with a thin film
 magnetic material, overcoated with a proprietary protective layer for
 improved durability and environmental protection.


 Defect and Error Management
 ---------------------------
 The WREN 7, as delivered, complies with this specification. The read
 error rate and specified storage capacity are not dependent upon use
 of defect management routines by the host (initiator).

 Defect and error management in the SCSI system involves the WREN 7
 internal defect/error management and SCSI systems error
 considerations (error in communications between host and WREN 7).
 Tools for use in designing a defect/error management plan are briefly
 outlined in this section, with references to other sections where
 further details are given.


 WREN 7 Internal Defect/Errors
 -----------------------------
 Identified defects are recorded on the WREN 7 defects list tracks
 (referred to as the primary or ETF defect list). These known defects
 are reallocated during the initial WREN 7 format operation at the
 factory. The WREN 7 internal retries and data correction by ECC
 should be enabled to recover data from additional flaws if they
 occur. If data correction by ECC is required to recover data, the
 host should immediately reallocate this sector by use of the Reassign
 Blocks command. If the WREN 7 automatic retries and data correction
 by ECC are disabled, defects are usally unrecoverable and need to be
 reallocated as they are discovered. For reallocation of bad sectors,
 the number of spare sectors per track or cylinder and the number of
 spare tracks per volume is programmable. After formatting, defects
 can be automatically reallocated by the WREN 7, or can be reallocated
 when the host sends the Reassign Blocks Command.


 Seek Time
 ---------
        ----------------------------------+--------+
        Track-to-Track         msec. typ. |   2.5  |
                               msec. max. |   4.0  |
                       Average msec. typ. |  15    |
                       Average msec. max. |  16.5  |
        Maximum Seek Time      msec. typ. |  34    |
                               msec. max. |  37    |
        Latency                msec. avg. |   8.33 |
        ----------------------------------+--------+


    Including Controller Overhead
    -----------------------------
        ----------------------------------+--------+
        Track-to-Track         msec. typ. |   3.20 |
                               msec. max. |   4.75 |
                       Average msec. typ. |  15.75 |
                       Average msec. max. |  17.30 |
        Maximum Seek Time      msec. typ. |  34.85 |
                               msec. max. |  37.90 |
        Latency                msec. avg. |   8.33 |
        ----------------------------------+--------+


 Temperature
 -----------
 The drive will meet all specifications over a 50*F to 122*F (10*C to
 50*C) drive ambient temperature range with a maximum gradient of 36*F
 (20*C) per hour. The enclosure for the drive should be designed such
 that the temperatures at the locations are not exceeded. Air flow may
 be needed to achieve these temperature values. Operation at case
 temperatures above these values may adversely affect the drives
 ability to meet specification.


 Heat/Power Dissipation
 ----------------------
 For drives with single ended interface circuits, typical dissipation
 is 31 watts (106 BTUs per hour) of DC power average at nominal
 voltages. Typical power dissipation under idle conditions is 24 watts
 (82 BTUs per hour).

 For drives having differential interface circuits, typical power
 dissipation is 32 watts (109.2 BTUs per hour) of DC power average
 at nominal voltages. Typical power dissipation under idle conditions
 is 25 watts (85.3 BTUs per hour).


 Reliability
 -----------
 The following reliability specifications assume correct host/drive
 interface including all interface timings, power supply voltages,
 environmental requirements.

 MTBF                     100,000 hours
 Service Life             5 years
 Preventive Maintenance   None required


