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Hard Drive: CDC: WREN VIHH 94244-164 145MB 5.25"/HH IDE / AT

W R E N   V I H H   9 4 2 4 4 - 1 6 4    CDC
NO MORE PRODUCED                                      Native|  Translation
Form                 5.25"/HH              Cylinders    1747|     |     |
Capacity form/unform   145/  164 MB        Heads           3|     |     |
Seek time   / track  16.0/ 3.0 ms          Sector/track   54|     |     |
Controller           IDE / AT              Precompensation
Cache/Buffer            32 KB LOOK-AHEAD   Landing Zone
Data transfer rate    1.549 MB/S int       Bytes/Sector      512
                      5.000 MB/S ext
Recording method     RLL 2/7                        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          15.0 W     Shock        g        10       |     40
       seek          20.0 W     Rotation   RPM      3592
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit
                                MTBF         h     100000
                                Warranty Month
Lift/Lock/Park     YES          Certificates     CSA,IEC380,IEC435,UL478,VDE  



  +--------------------------------------------------------+  1
  |                                                        |XX Power
  |                                                        |XX
  |                                                        |
  |                                                        |+-1
  |                                                        || |J2
  |                                                        || |
  |                                                        |+-+
  |                                                        |
  |                                                        |XX
  |                                                        |XX 40 pin
  |                                                        |XX I/O
  |                                                        |.X
  |                                                        |XX
  |                                                        |XX
  |                                                        |XX
  |                                                        |XX1



Jumper setting

x = Jumpers set at factory

J2 Drive Select

        |  G  F  E  D  C  B  A  |
   -----+-----------------------+----- PWA

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. Connections to
external devices (switches, connectors, etc.) could adversely affect
drive performance. Exact location of these pins and headers may
change without notice.

 A          B
 OFF        OFF    Factory use only.
 OFF        ON     Drive is slave, motor start delays 12 sec. from
                   master start-up.
 ON         OFF    Drive is slave, no motor start delay
 ON         ON     Drive is master. Motor starts at application of DC

When it is necessary to remove jumpers for desired configuration, do
not store the removed jumper plugs on any other pins of the
configuration selection header, as that will cause the drive to oper-
ate incorrectly.

 C          D
 OFF        OFF    Physical mode.
 OFF        ON     Translate (logical) mode, sparing scheme is one
                   sector per track.
 ON         OFF    Translate (logical) mode. No sparing space
 ON         ON     Factory use only.

The WREN 6HH (AT interface) operates in either a translate or a
non-translate mode. To operate in the translate mode, a Translate
Mode jumper configuration must be installed on the configuration
select header, and the host must set up in the drive the logical
characteristics of the drive when communication with the host.

OFF Slave present. Only meaningful on master.
ON No slave present.

F & G
Factory Test.
Jumper position F and G must not be used. Position G may or may not
be present depending upon PWA.

DC Power Connector

              |+5V  +5V  +12V  +12V |
              |      Ret  Ret       |



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!
      Never install PC board on the Top!

Drive Orientation
Only two WREN 6HH mounting orientations are permitted: discs in the
horizontal plane and discs in the vertical plane. Horizontal mounting
with the front raised at an angle of 15* is acceptable. Mounting with
either end down (front or rear) or upside down is not permissible. It
is recommended that data written in a given orientation by read in
that same orientation.

WREN 6HH (AT interface) 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 6HH (At interface) into an OEM's system, wether
in a factory or field environment.

Cabinet cooling must be designed by the customer so that the ambient
temperature immediately surrounding the WREN 6HH (AT interface) will
not exceed temperature conditions. Specific consideration should be
given to make sure adequate air circulation is present around the
components on the PWAs.

Service Tools
No special tools are required for site installation or recommended
for site maintenance. The depot repair philosophy of WREN 6HH (AT
interface) precludes the necessity for special tools. Should field
repair of items external to the HDA be desired, one 6 point size
T10 Torx driver is required. This hand tool may be ordererd through
most commercial tool catalogs.

Air Cleanliness
The WREN 6HH (AT interface) is designed to operate in a typical
office environment with minimal environment control.

Interface Cabling Options
The ST2274A/383A is capable of operating on the AT bus in a daisy
chained configuration with a second drive/controller that operates
in accordance with these specification. One drive is designated as
master and the other as the slave.

         |                  HOST                   |
         |        I/O                              |
         +---------+--+  +----------+--+
         |   'AT'     |  |   'AT'      |
         |   WREN     |  |   WREN      |
         +------------+  +-------------+

DC Cable and Connector
The WREN 6HH (AT interface) receives DC power through a 4 pin
connector mounted on the main circuit board. Recommended part numbers
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)

I/O Cable and Connector
The I/O connector is a 40 pin connector. A key is provided by the re-
moval of Pin 20. The corresponding pin on the cable connector should
be plugged. Seagate recommends keying this connector to prevent the
possibility of installing it upside down.

Maximum I/O cable length is 24 inches (.61 metres).
Recommended part numbers for the mating connector are included below,
but equivalent parts may be used.

 Connector:          40 pin, 3M-3417-7000 (Strain relief 3448-2040)
 Cable:              Flat Cable (Stranded AWG 28) 3M-3365-40
                     Flat Cable (Stranded AWG 28) 3M-3517-40 (Shielded



General Description
The WREN 6HH (AT interface) is a half height member of a family of
low cost, high performance, highly reliable, random access storage
devices designed to meet the needs of the OEM marketplace.

The WREN 6HH (AT interface) has been developed as a system
peripherals to the highest standards of design and construction. The
WREN 6HH (AT interface) 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

The WREN 6HH (AT interface) complies with Seagate standards.

The WREN 6HH is a UL Recognized component per UL 478 and a CSA
Certified component 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 EN 60950/09.87.

The WREN 6HH product as delivered, is designed for system integration
and installation into a suitable enclosure prior to use. As such, the
WREN 6HH is supplied as a sub-assembly and is not subject to Subpart
J of Part 15 of the FCC Rules and Regulations nor the Radio
Interference Regulations of the Canadian Department of
Communications. However, the unit has been tested using proper
shielding and grounding and found to be compliant with the Class A
limits of the FCC Rules and the Regulations of the Canadian Depart-
ment of Communications.

The Head/Disc/Actuator Assembly (HDA) is environmentally sealed at
the factory. Air is recirculated within the HDA through a nonreplace-
able filter to ensure the maintenance of a contamination free disc/
actuator environment.

The WREN 6HH (AT interface) 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.
Head parking is done automatically by the WREN 6HH. The Host can not
send a command that sends the heads to the parking zone.

The WREN 6HH (AT interface) 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 6HH (AT interface) decodes Track 0 location from the
dedicated servo surface thereby eliminating mechanical transducer
adjustments and related reliability concerns.

The WREN 6HH (AT interface) uses a high performance actuator assembly
consisting of a low inertia, balanced, patented, straight arm driven
by a highly efficient pancake coil assembly. This patended actuator
mechanism provides excellent performance with minimal power dissipa-

Media Description
The media used on the WREN 6HH (AT interface) 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

Each data surface has a total of 1747 tracks and is capable of
recording 54,716,040 bytes of unformatted data.

Media defects are characterized as correctable or uncorrectable de-
pending on the type and magnitude of the media flaw. WREN 6HH (AT
interface) media certification is performed using the following

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

            An error burst greater than 11 bits in length is an un-
            correctable error.

At the time of shipment from the point of manufacture, the WREN 6HH
(AT interface) recording surfaces meet the following requirements.

       1. 1747 total tracks per surface.

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

       3. 50 defects per surface maximum.

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

Defect Deallocation and Factory Defect Maps
Media verification is performed during the factory burn-in period.
Standard configurations, as shipped from the factory, have all
physical sectors containing defects reformatted with the bad block
bit set. The scetors are also relocated so that sector 54 falls over
the defect and will be undetected if the alternate (spare) sector
mode is jumper selected. A map of the defective sectors is written to
several locations on the drive using physical addresses. The host can
configure the drive to a logical configuration when installed in the
host system.

If there are multiple defective sectors on a track, the entire track
will be formatted with Bad block bits set.

The physical addresses of the defects are written to all heads,
sector 1 through 4 on physical cylinder address 1023, 1746 and 4095
(-1) of the drive.

The copies of the defect map use the following format: Each entry is
a four byte hexadecimal number. The first two bytes are the cylinder
number with the least significant byte first. The third byte is the
head number, and the fourth byte is the sector number. All drives
are shipped with cylinder zero defect-free. An entry of a cylinder
number of zero indicates the end of the defect map. The last 19 bytes
of sector four contain in ASII "PHYSICAL *DEFECT* MAP".

Translate Mode Capacity (logical, apparent values)
The ST2274A/383A WREN 6HH has an embedded controller that has the
capability to translate the drive's actual, physical heads and
cylinders values to logical, apparent values when communicating with
a host controller. Thusa host system not having a disc drive table
entry that fits the ST2274A/383A WREN 6HH can install the ST2274A/
ST2383A WREN 6HH as a drive having a heads and cylinders to whatever
they need to appear to be install on the host system as the selected
type. The capacity achieved in the translate mode depends on the
logical configuration to which the WREN 6HH "translates".

Seek Time

                                          |WREN 6HH|
        Track-to-Track         msec. typ. |   3    |
                               msec. max. |   5    |
                       Average msec. typ. |  16    |
                       Average msec. max. |  18    |
        Latency                msec. avg. |   8.35 |
 Seek time is defined as the required time from the receipt of a Seek
 Command by the WREN 6HH (AT interface) until the completion of the
 seek operation. Average seek time is determined by dividing the sum
 of the time for all possible seek movements by the total number of
 seek movements.

Spindle Speed and Latency
The spindle speed is 3592 0.5% r/min. The speed tolerance includes
motor performance and motor control circuit tolerances.

The average latency time is 8.35 milliseconds, based on a nominal
disc speed of 3592 r/min. The maximum latency time is 16.7 milli-
seconds based on a minimum disc speed of 3574 r/min.

Host/Drive Interface data transfer rate
Maximum instantaneous: 5,000 kbytes/s
Maximum average: 1,549 kbytes/s

Power Sequencing
Power sequencing is not required for the WREN 6HH. If the Delayed
Motor Start jumper configuration is off, the slave drive motor start-
up is delayed 20 seconds from power on.

The drive will meet all specifications over a 50*F to 122*F (10*C to
50*C) 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. A small
amount of air flow may be needed to achieve these temperature values.

Write Precompensation Cylinder
The starting cylinder for write precompensation is controlled by the
contens of this register. The starting physical cylinder is 4 times
value in this register. This register is ignored by the WREN 6HH
'AT'. Use of write precompensation is controlled by the drive.

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 circuit to the host system.

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

previous page: Hard Drive: CDC: WREN VIHH 94241-502 337MB 5.25"/HH   SCSI1 SE
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