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Hard Drive: CDC: WREN IIHH 94205-77 66MB 5.25"/HH RLL ST412




W R E N   I I H H   9 4 2 0 5 - 7 7    CDC
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 5.25"/HH              Cylinders     989|     |     |
Capacity form/unform    66/   77 MB        Heads           5|     |     |
Seek time   / track  28.0/ 5.0 ms          Sector/track   26|     |     |
Controller           RLL / ST412           Precompensation   128
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        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          18.0 W     Shock        g         2       |     32
       seek          20.0 W     Rotation   RPM      3600
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit
                                MTBF         h      40000
                                Warranty Month
Lift/Lock/Park     YES          Certificates     CSA,SDA,FCC,IEC380,IEC435,...

Layout

SEAGATE ST279R PRODUCT MANUAL 77765254-C

  +------------------------------------------------------+
  |                                                      |XX Power
  |                                                      |XX
  |                                                      |
  |                                        Terminator++  |X1 Control
  |                                        Resistor  ||  |XX Cable
  |                                                  ||  |XX Connector
  |                                                  ++  |XX
  |                                                      |XX
  |                                          Drive   +-+ |XX
  |                                          Select  | | |XX
  |                                          Jumper  | | |
  |                                                  +-+ |X1 Data
  |                                                      |XX Cable
  |                                                      |XX Connector
  |                                                      |XX
  |                                                      |XX
  +------------------------------------------------------+

Jumpers

SEAGATE ST279R PRODUCT MANUAL 77765254-C

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

Drive Select Jumper
-------------------

      +------------+--------------------+
      |            | 1  2  3  4  5  6  7|
      +------------+--------------------+
      |Drive 1     | X  o  o  o  o  o  o|
      |            | X  o  o  o  o  o  o|
      +------------+--------------------+
      |Drive 2     | o  X  o  o  o  o  o|
      |            | o  X  o  o  o  o  o|
      +------------+--------------------+
      |Drive 3     | o  o  X  o  o  o  o|
      |            | o  o  X  o  o  o  o|
      +------------+--------------------+
      |Drive 4     | o  o  o  X  o  o  o|
      |            | o  o  o  X  o  o  o|
      +------------+--------------------+
      |Radial      | o  o  o  o  X  o  o|
      |            | o  o  o  o  X  o  o|
      +------------+--------------------+
      |Reserved    | o  o  o  o  o  X  o|
      |            | o  o  o  o  o  X  o|
      +------------+--------------------+
      |Reserved    | o  o  o  o  o  o  X|
      |            | o  o  o  o  o  o  X|
      +------------+--------------------+

 WREN Interface Control Cable
 ----------------------------
                  Signal Direction    Signal Direction
   +-----------+                                      +-------------+
   |           |                                      |Signal Ground|
   |           | Terminated                           |No.    No.   |
   |           +------------------------------------->|  2     1    |
   |           | Head Select 2(2)                     |             |
   |           +------------------------------------->|  4     3    |
   |           | Write Gate                           |             |
   |           +------------------------------------->|  6     5    |
   |           | Seek Complete                        |             |
   |           |<-------------------------------------+  8     7    |
   |Controller/| Track 0                              |             |
   |Host       |<-------------------------------------+ 10     9    |
   |Interface  | Write Fault                          |             |
   |           |<-------------------------------------+ 12    11    |
   |           | Head Select 2(0)                     |             |
   |           +------------------------------------->| 14    13    |
   |           | Reserved  to J3 pin 7                |             |
   |           +--------------------------------------+ 16    15    |
   |           | Head Select 2(1)                     |             |
   |           +------------------------------------->| 18    17    |
   |           | Index                                |             |
   |           |<-------------------------------------+ 20    19    |
   |           | Ready                                |             |
   |           |<-------------------------------------+ 22    21    |
   |           | Step                                 |             |
   |           +------------------------------------->| 24    23    |
   |           | Drive Select 1                       |             |
   |           +------------------------------------->| 26    25    |
   |           | Drive Select 2                       |             |
   |           +------------------------------------->| 28    27    |
   |           | Drive Select 3                       |             |
   |           +------------------------------------->| 30    29    |
   |           | Drive Select 4                       |             |
   |           +------------------------------------->| 32    31    |
   |           | Direction In                         |             |
   |           +------------------------------------->| 34    33    |
   |           |                                      |             |
   +-----------+                                      +-------------+
                                                       WREN Control
                                                       Cable Connector

   All signals in the control cable are single ended signals.

Pin 2 in the control cable (Head Select 2(3) is defined as Reduced
Write Current in the Seagate ST412 interface. The WREN 2HH (RLL)
controls write current internally, and thus the line is not needed
for this function and is terminated.

 DC 506 Interface Data Cable
 ---------------------------
                  Signal Direction    Signal Direction
   +-----------+                                      +-------------+
   |           |                                      |Pin No. Type*|
   |           | Drive Selected                       |             |
   |           |<-------------------------------------+  1      SE  |
   |           | Ground                               |             |
   |           +--------------------------------------+  2          |
   |           | Reserved                             |             |
   |           +--------------------------------------+  3      SE  |
   |           | Ground                               |             |
   |           +--------------------------------------+  4          |
   |Controller/| Motor On (Option)                    |             |
   |Host       +--------------------------------------+  5      SE  |
   |Interface  | Ground                               |             |
   |           +--------------------------------------+  6          |
   |           | Reserved  to J4 Pin 16               |             |
   |           +--------------------------------------+  7          |
   |           | Ground                               |             |
   |           +--------------------------------------+  8          |
   |           | Reserved                             |             |
   |           +--------------------------------------+  9          |
   |           | Reserved                             |             |
   |           +--------------------------------------+ 10          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 11          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 12          |
   |           | +RLL Write Data                      |             |
   |           +------------------------------------->| 13      DIFF|
   |           | -RLL Write Data                      |             |
   |           +------------------------------------->| 14      DIFF|
   |           | Ground                               |             |
   |           +--------------------------------------+ 15          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 16          |
   |           | +RLL Read Data                       |             |
   |           |<-------------------------------------+ 17      DIFF|
   |           | -RLL Read Data                       |             |
   |           |<-------------------------------------+ 18      DIFF|
   |           | Ground                               |             |
   |           +--------------------------------------+ 19          |
   |           | Ground                               |             |
   |           +--------------------------------------+ 20          |
   |           |                                      |             |
   +-----------+                                      +-------------+
                                                       Data Cable
                                                       Connector

 * SE   = Single Ended Signal
   DIFF = Differential Signal

Drive Select 1-2-3-4
--------------------
These lines are used to activate a device's drivers and receivers for
up to four drives in a daisychained operation. The following
characteristics apply to the DRIVE SELECT lines:

  1.   Logical unit designation is accomplished at the time of
       installation by setting the jumper plug located on the
       baseboard assembly.

  2.   All control cable lines are gated with Drive Select. No data
       cable signal lines are gated with Drive Select.

  3.   Drive Select must remain active during any communication with
       the host controller.

  4.   When the radial select jumper is installed, the drive will be
       selected all the time.

  5.   The drive should not be selected until 1 second after DC power
       is applied. The Ready input will be valid within 500 ns
       after the drive is selected (Drive Selected true) and after the
       power on delay.

  6.   The drive will be selected within 1 us after the activation of
       Drive Select, if the power on sequence is complete. The drive
       will be the deselected within 1 us after the deactivation of
       Drive Select.

  7.   The drive will activate the data cable Drive Selected signal
       within 1 us after receipt of Drive Select if the drive is
       selected. The drive will deactivate Drive Selected within 1 us
       after the Drive Select signal is deactivated.

  8.   Drive Select must be valid 100 ns minimum before the first step
       pulse is received and 100 ns minimum after the last step pulse
       is received.

  9.   At the completion of a write operation, Drive select must
       remain active for 1 us.

 10.   When the Drive Select line is activated, a head change will
       occur, thus requiring a delay of 5 us before a read or write
       operation can be initiated.

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

Install

SEAGATE ST279R PRODUCT MANUAL 77765254-C

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
      UNACCEPTABLE!                                UNACCEPTABLE!

Drive Orientation
-----------------
The permissible drive mounting orientations include operation in the
horizonatal plane and in the vertical plane. Mounting with either end
down (front or rear) is not permissible. An angle of 15* up form the
horizontal (front end only) is acceptable for the horizontal
orientation.

WREN 2HH (RLL) is designed, manufactured, and tested with a "Plug-in
and Play" installation philosophy. Basically, this philosophy
minimizes the requirements for highly trained personnel to integrate
the WREN 2HH (RLL) into the OEM's system, whetherin a factory or
field environment.

Cooling
-------
The cabinet cooling must be designed by the customer so that the
ambient temperature immediately surrounding the WREN 2HH (RLL) will
not exceed temperature conditions.

Interface Cabling Options
-------------------------

 View A
    +---------------------Host-Controller---------------------+
    |                                                         |
    |Data Control   Data Control  Data Control   Data Control |
    +--+-----+--------+-----+--------+-----+--------+-----+---+
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
       |     |        |     |        |     |        |     |
    +-++-+--++-+-+ +-++-+--++-+-+ +-++-+--++-+-+ +-++-+--++-+-+
    | |R |  | T| | | |R |  | T| | | |R |  | T| | | |R |  | T| |
    | +--+  +--+ | | +--+  +--+ | | +--+  +--+ | | +--+  +--+ |
    |    WREN    | |   WREN     | |   WREN     | |   WREN     |
    +------------+ +------------+ +------------+ +------------+

    Each control cable length must not exceed 20 feet (6.10m). Each
    data cable length must not exceed 20 feet (6.10m).

   T  indicates terminator resistor pack.
   R  indicates discrete terminator.
   WREN data cables are permanently terminated.

Radial Configuration
--------------------
View A shows each drive interfaced to its own control cable which,
allows interfacing of any number of drives and a variety of
system operational techniques. Each drive has its data cable and
control cable radially connected to the host controller. The length
of each individual cable must not exceed 20 feet (6.10 metres).
Terminator resistors must be installed in the host controller for
each data cable and for each control cable. Each drive requires a
terminator for the control cable.

 View B
    +---------------------Host-Controller---------------------+
    |                                                         |
    |Data Control   Data          Data           Data         |
    +-+------+-------+--------------+--------------+----------+
      |      |       |              |              |
      |      |       |              |              |
      |      |       |              |              |
      |      +-------+Control+------+Control+------+Control+
    +++-+----+---+ +++-+-----+--+ +++-+-----+--+ +++-+----++-++
    ||R |        | ||R |        | ||R |        | ||R |    | T||
    |+--+        | |+--+        | |+--+        | |+--+    +--+|
    |    WREN    | |    WREN    | |    WREN    | |    WREN    |
    +------------+ +------------+ +------------+ +------------+

    Total control cable length must not exceed 20 feet (6.10m). Each
    data cable length must not exceed 20 feet (6.10m).

   T  indicates terminator resistor pack.
   R  indicates discrete terminator.
   WREN data cables are permanently terminated.

Daisychain Configuration
------------------------
A daisychain configuration incorporates parallel interfacing of the
disc drives on a common control cable. A maximum of four drives may
be daisychained on the control cable. Only the drive which is
selected by the host system has its control and data signals enabled
through this common interface. View B consists of four WREN 2HH (RLL)
disc drives only. A terminator resistor pack is required in the host
controller for each data cable. Only the last WREN 2HH (RLL) in the
daisychain requires a terminator resistor pack for the control cable.
Terminator resistor packs for the control cable or other drives are
removed. The total combined control cable length (from the controller
to the first drive, to the second and subsequent drives) must not be
more than 20 feet (6.1 metres).

DC Cable and connector
----------------------
The WREN 2HH (RLL) receives DC power through a 4 pin right angle
connector mounted on the main circuit board. Recommended part number
for the mating connector are included below, but equivalent parts may
be used.

Type of cable: 18 AWG
Connector: AMP 1-480424-0
Contacts: AMP 60619-4 (Loose Piece); AMP 61117-4 (Strip)

Device Grounding
----------------
The WREN 2HH (RLL) is shipped with the DC Logic ground and the
chassis ground joined together. These two ground planes may be
separated by repositioning the motor control board ground washer.

Note: If the grounds are to be separated, the washer must be oriented
so that it does NOT contact the ground run near the screw AT ANY
POINT.

System Ground Quick Connect Terminal
------------------------------------
System ground may be connected to the Quick connect terminal.
Recommended part numbers for this connector and the mating connector
are listed, but equivalent parts may be used.

 Drive Connector Terminal          Cable Connector Terminal
 ------------------------          ------------------------
     AMP P/N 61664-1                   AMP P/N 62137-2

Data Cable and Connector
------------------------
The I/O connector for the data interface is a 20 pin board edge
connector. The odd pins are located on the front side of the
printed circuit board. The even pins are on the back side of the
printed circuit board. A key slot is provided between pins 3 and 5.
Seagate recommends keying this connector to prevent the possibility
of installing it upside down.

Recommended part numbers for the mating connector are included below,
but equivalent parts may be used.

 Connector:          20 pin, 3M-3461-0001, AMP 88373-6 or AMP 111109-3
 Cable:              Flat Cable (Stranded AWG 28) 3M-3365-20
                     Flat Cable (Stranded AWG 28) 3M-3517-20 (Shielded
                     Cable)
 Key:                AMP 583274-1, 3M-3439-0000

Control Cable and Connector
---------------------------
The I/O connector for the control interface is a 34 pin board edge
connector. The odd pins are located on the front side of the
printed circuit board and are connected to the ground plane. The even
pins are on the back side of the printed circuit board. A key
slot is provided between pin 3 and 5. Seagate recommends keying this
connector to prevent the possibility of installing it upside down.

Recommended part numbers for the mating connector are included below,
but equivalent parts may be used.

 Connector:          34 pin, 3M-3463-0001, AMP 88373-3 or AMP 111109-3
 Key:                AMP 583274-1, 3M-3439-0000
 Cable:              Flat cable (Stranded AWG 28) 3M-3365-34
                     Flat cable (Stranded AWG 28) 3M-3517-34 (Shielded
                     Cable)
                     Spectra Strip Twist'n Flat 455-248-34 (Stranded
                     AWG 28 Twisted Pair)

Interface Drivers/Receivers
---------------------------
The WREN 2HH (RLL) uses both single ended and balanced differential
signals on the I/O. The data signals use balanced differential
drivers and receivers. All other signals use single ended drivers and
receivers.

Single Ended Drivers/Receivers
-------------------------------
Transmitter Characteristics
The WREN 2HH (RLL) uses the 74F38 open collector quad-2-input driver
to transmit status to the host. This driver is capable of sinking a
current of 48 mA with a low-level output voltage of 0.4V.

Receiver Characteristics
The WREN 2HH (RLL) uses the 74LS14 Hex Inverter with hysteresis gate
as a line receiver. The input of each receiver is terminated in a
220/330 ohm resistor network.

Terminator Characteristics
The terminator consists of a resistor module which plugs into a
socket in the last drive in a daisychain. Each drive is furnished
with a terminator. Terminators must be removed from all except the
last drive on the cable prior to daisychain operation. The terminator
can be easily removed with tweezers or needlenose pliers.
An equivalent terminator must be provided in the controller on each
input signal line from the drive to the controller. Only the control
cable resistor module is removable.

 Balanced Differential Drivers/Receivers
 ---------------------------------------
 Transmitter Characteristics
 The WREN 2HH (RLL) uses 75158 type balanced differential driver.
 Logic 1 on the interface is defined when the "+" output is more
 positive than the "-" output.

 Receiver Characteristics
 ------------------------
 The WREN 2HH (RLL) uses 75157 type balanced differential receivers.
 Logic 1 on the interface is defined when the "+" input is more
 positive than the "-" input.

Terminator Requirements
-----------------------
Each differential receiver in the drive is terminated with a 100 ohm
resistor. An equivalent terminator must be provided in the controller
on each input signal line from the drive to the controller.

Digital Interface Signal Definitions
------------------------------------
The WREN 2HH (RLL) uses the two cable (control and data) interface
for information transfer between it and the controller/host system.
(All single ended signals are true when the interface voltage level
is less than 0.4 volts.)

Remote Motor Start
------------------
The WREN 2HH (RLL) will support remote start control capability via a
user specified option. This option utilizes a reserved line on the
data cable (pin number 5) to enable the motor ON routine in the
drive. If this option is not selected, Pin 05 will be open and non-
functional. If this option is installed, Pin 05 will start the
spindle concurrent with a high level.

Features

SEAGATE ST279R PRODUCT MANUAL 77765254-C

Standards
---------
The 94205-77 WREN 2HH (RLL) has been developed as a system
peripherals to the highest standards of design and construction. The
WREN 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 WREN 2HH (RLL)is a UL Recognized component per UL478 and a CSA
Certified product per CSA C22.2, No. 220-M1986. It also meets the
requirements of DIN IEC 380/VDE 0806/8.81, DIN IEC 435/VDE 0805/11.84
and EN60950/09.87.

The WREN 2HH (RLL), as delivered, is designed for system integration
before use. It is supplied as a Class A Computing Device per the FCC
Rules and Regulations, Part 15, Subpart J, governing EMI of computing
devices and Radio 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 a contamination
free disc/actuator environment.

The WREN 2HH (RLL) 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 WREN 2HH (RLL) incorporates an automatic shipping look which
prevents potential damage to the heads and disks caused by movements
during shipping and handling. The shipping lock is automatically
disengaged when power is applied to the drive.

The WREN 2HH (RLL) decodes Track 0 location from the dedicated servo
surface thereby eliminating mechanical transducer adjustments and
related reliability concerns.

The WREN 2HH (RLL) uses a high performance actuator assembly
consisting of a low inertia, balanced, straight arm driven by a
by a highly efficient pancake coil assembly. This actuator mechanism
(patent pending) provides excellent performance with minimal power
dissipation.

Media Description
-----------------
The media used on the WREN has a diameter of approximately 5
inches (130 mm). The aluminum substrate is coated with lubricated
ferrous oxide which permit the heads to contact the surface when
starting and stopping.

Each data surface has total of 989 tracks and is capable of record-
ing 15,452,136 bytes of unformatted data.

Media defects are characterized as beeing either correctable or
uncorrectable as a function of the type and magnitude of the media
flaw. Various error correction codes may be implemented to correct
errors in the data read from the disk. However, the code chosen
should be consistent with Control Data media testing and
certification methods. In the WREN 2HH (RLL) media certification is
performed using the following standards:

        An error burst of 11 bits or less is a correctable error.

        An unorrectable error is one greater than 11 bits in length.

Host systems using the WREN 2HH (RLL) should have, as a minimum,
resident capabilities to recognize and map defective tracks and
perform track reallocation routines.

At the time of shipment from the point of manufacture, the WREN 2HH
(RLL) recording surfaces will meet the following requirements.

       1. 989 total tracks per surface.

       2. Track 0 to be error free on each data surface.

       3. 30 defects per surface maximum.

       4. Accumulative defects not to exceed 1.5 per megabyte, based
          on total available unformatted drive capacity.

       5. Unidentified correctable errors shall not exceed two per
          surface.

Driver/Receiver Characteristics
-------------------------------
Logic Level Drive Output Receiver Input
--------------------------------------------------------------------
High (False/Negated) (0) 2.5 V; 5.25 V 2.0 V; 5.25 V
Low (True/Asserted) (1) 0.4 V; 0.0 V 0.5 V; 0.0 V

The difference in the voltages between input and output signals is
due to the losses in the cable.

Seek Time
---------

                                          | WREN II|
        ----------------------------------+--------+
        Track-to-Track         msec. typ. |   5    |
                               msec. max. |   8    |
                       Average msec. typ. |  28    |
                       Average msec. max. |  37    |
        Maximum Seek Time      msec. typ. |  65    |
                               msec. max. |  80    |
        Latency                msec. avg. |   8.34 |
        ----------------------------------+--------+

Seek time is defined as the time required from the receipt of a seek
or position command by the WREN 2HH (RLL) until the drive signals
the controller that it is ready to perform another seek or a
read/write function on the new cylinder. Average seek time is
determined by dividing the sum of the time for all possible movements
by the total number of movements.

Start/Stop Time
---------------
The WREN 2HH (RLL) will become ready less than 35 seconds after
application of DC power. Stop time will be less than 30 seconds after
removal of DC power.

There is no power control switch on the drive. Power should not be
removed by pulling out the power cable to the drive.

Spindle Speed and Latency
-------------------------
The spindle speed is 3597 0.5% r/min. The speed tolerance includes
motor performance and motor control circuit tolerances.

The average latency time is 8.34 milliseconds, based on a nominal
disc speed of 3597 r/min. The maximum latency time is 16.76 milli-
seconds based on a maximum disc speed of 3579 r/min.

Read Data Transfer Rate
-----------------------
The nominal read serial data transfer rate is 7.5 Mbits per second.

Air Cleanliness
---------------
The WREN 2HH (RLL) is designed to operate in a typical office
environment with minimum environmental control.

Power Sequencing
----------------
Power sequencing is not required for the WREN 2HH. It protects
against inadvertent writing during power up and down. Daisychain
operation requires that power be maintained on the terminated unit to
ensure proper termination of the peripheral I/O.

Heat/Power Dissipation
----------------------
Each WREN 2HH (RLL) will typically dissipate 20 watts (68 BTU per
hour) of power during operation (seeking). Idle mode power
dissipation is less than 18 watts, typically.

Temperature
-----------
50*F to 122*F (10*C to 50*C) operating ambient with a maximum
gradient of 18* F (10* C) per hour. Above 1000 feet (305 metres)
altidude the maximum temperature is derated linearly to 112* F
(44*C) at 10,000 feet (3048 metres). Cabinet packaging designs must
provide ample air circulation around the WREN 2HH (RLL) to make sure
environmental limits are not exceeded as a result of heat transfer
from other system components. Operating ambient for specification
purposes is defined as the environment immediately surrounding the
WREN 2HH (RLL). The temparature of the HDA is restricted to a maximum
of 143*F (62*C) during operation.

Reliability
-----------
The following reliability specifications assume correct host/drive
operational interface has been implemented, including all interface
timings, power supply voltages, environmental conditions, and
appropriate data handling circuits in the host system.

MTBF 40,000 hours
Service Life 5 years
Preventive Maintenance None required













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