S T 2 2 5 R    SEAGATE
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 5.25"/HH              Cylinders     667|     |     |
Capacity form/unform    21/   25 MB        Heads           2|     |     |
Seek time   / track  70.0/20.0 ms          Sector/track   31|     |     |
Controller           RLL / ST412           Precompensation 65535
Cache/Buffer               KB              Landing Zone      670
Data transfer rate    0.938 MB/S int       Bytes/Sector      512
                      0.938 MB/S ext
Recording method     RLL 2/7                        operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C        15 45    |    -40 60
Power: sleep              W     Humidity     %         8 80    |      5 90
       standby       14.8 W     Altitude    km    -0.305  3.048| -0.305  9.140
       idle               W     Shock        g        10       |     40
       seek               W     Rotation   RPM      3000
       read/write    33.0 W     Acoustic   dBA
       spin-up            W     ECC        Bit
                                MTBF         h     100000
                                Warranty Month
Lift/Lock/Park     NO           Certificates     CSA,TUV,UL478,VDE            

**********************************************************************
                        L   A   Y   O   U   T
**********************************************************************
SEAGATE  ST213/ST225/ST225R/ST238R/ST250R  PRODUCT MANUAL 36025-003

  +---------------------------------------------------------+
  |                                                         |XX
  |                                                         |XX J2
  |                                                         |XX
  |                                                         |XX
  |                                                         |+-16
  |                                                         || |J7
  |                                                         || |
  |                                                         |+-2
  |                                Resistor        +-+      |XX
  |                                Termination     | |      |XX
  |                                Pack            | |      |XX
  |                                                +-+      |XX
  |                                                         |XX J1
  |                                                         |XX
  |                                                         |
  |                                                         |XX Power
  |                                                         |XX J3
  +---------------------------------------------------------+



**********************************************************************
                      J   U   M   P   E   R   S
**********************************************************************
SEAGATE  ST213/ST225/ST225R/ST238R/ST250R  PRODUCT MANUAL 36025-003

 Jumper setting
 --------------
 x = Factory setting


 JP7  Drive select  Configuration Jumper block
 ----------------------------------------------
      +-------------+------+------+------+------+
      |Drive Select | 9-10 |11-12 |13-14 |15-16 |
      +-------------+------+------+------+------+
      |Drive 4      |CLOSED|OPEN  |OPEN  |OPEN  |
      |Drive 3      |OPEN  |CLOSED|OPEN  |OPEN  |
      |Drive 2      |OPEN  |OPEN  |CLOSED|OPEN  |
      |Drive 1      |OPEN  |OPEN  |OPEN  |CLOSED|
      +-------------+------+------+------+------+
 The Drive Select line enables the controller to select and adress
 the drive. Control cable interface options may use either a daisy-
 chain or radial configuration.


 JP7  Manufacturing test
 -----------------------
 x     7- 8   OPEN  Do not install a jumper on the Manufacturing Test
                    jumper on the user configuration jumper block.
                    This is a test function and used during the manu-
                    facturing process ans is not recommended for field
                    use. When the pins are shorted, the stepper motor
                    will continuously seek between Track 0 and the
                    maximum cylinder and will ignore control signals
                    via the interface.


 JP7  Write Fault
 ----------------
 x     5- 6   OPEN  The Write Fault signal may be internally latched.
                    It may be enabled by shorting pins 5-6 at J7. This
                    latch may be cleared when Drive Select goes false
                    (if selected). The standard configuration, with
                    the shorting block removed, causes Write Fault to
                    go false when Write Gate goes false.
                    Not required for standard operation.


 JP7  Recovery Mode
 -----------------
 x     3- 4   CLOSE Recovery Mode is a read/write head microstepping
                    option on the ST225R and ST250R. It is enabled by
                    shorting pins 3-4 at J7. THE ST225R AND ST250R ARE
                    SHIPPED WITH THIS OPTION ENABLED.

 Recovery Mode is initiated when the controller asserts the Recovery
 Mode line true at the interface. This changes the step line to a
 microstep function after 100 nsec. A step pulse will now cause Seek
 Complete to go false 100 nsec. after the drive receives the pulse.
 The drive then microsteps off-track using the optimum algorithm,
 allowing time for the read/write heads to settle and then takes the
 Seek Complete line true.

 The controller may then read data. If data is not read correctly, the
 controller may issue an additional step pulse. Up to 2 microstep
 algorithms may be accessed before the sequence is repeated.

 When data is read correctly, the controller exits Recovery Mode by
 taking the Recovery Mode line false at the interface. The drive will
 then return the heads to the nominal position by taking Seek Complete
 false, allowing time for the heads to settle, and resasserting Seek
 Complete.


 JP7  Radial/Daisy-Chain Mode
 ----------------------------
 x     1- 2   OPEN  Daisy-Chain-Configuration
                    A Daisy-Chain configuration allows connection of
                    a maximum of two drives on a common control cable.
                    A separate data cable is required for each drive.
                    The last drive in the chain (physically farthest
                    from the controller) requires termination. All
                    other drives should not be terminated. The maxi-
                    mum permitted cable length from the controller to
                    the last drive is 10ft (0.31m).
       1- 2   CLOSE Radial Configuration
                    To configure the drive radially, install a jumper
                    on pins 1 and 2 of the user configuration jumper
                    block. If you configure the drive radially, leave
                    the resistor terminator packs installed on all
                    drives. Each radially connected drive has its own
                    control and data cable. Drives in this configu-
                    ration always remain selected.


 J3  DC Power and pin connector assignments
 ------------------------------------------
      +------------+   pin 1    +12 VDC
      | 1  2  3  4 |   pin 2    +12 VDC Gnd
      +------------+   pin 3    + 5 VDC Gnd
                       pin 4    + 5 VDC


**********************************************************************
                      I   N   S   T   A   L   L
**********************************************************************
SEAGATE  ST213/ST225/ST225R/ST238R/ST250R  PRODUCT MANUAL 36025-003

 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!

 The drive may be mounted horizontally with the PC board down or on
 either side. Mounting vertically on either end is a prohibited orien-
 tation.
 The drive should not be tilted front or back, in any position, by
 more than 5*. For optimum performance, the drive should be formatted
 in the same position as it will be mounted in the host system.

 The mounting screws must not exceed inside the mounting feet more
 than 3.2 mm, measured from the outside surface of the foot.


 Interface and Recording Method
 ------------------------------
 The ST213 and ST225 are designed for operation with the ST412 inter-
 face with  MFM encoding at 5.0 MBits/sec. data transfer rate. Opera-
 tion of a MFM drive with a RLL controller is not approved by SEAGATE
 and will void the drive warranty.

 The ST225R, ST238R and ST250R are designed for operation with the
 ST412 interface with Run Length Limited (2,7) encoding at 7.5 Mbits/
 sec. data transfer rate.


 Radial/Daisy-Chain Mode
 ------------------------
 The Drive Select line enables the controller to select and address
 the drive. Control cable interface options may use either a Daisy-
 Chain or Radial configuration.

 Drives can be configured in either a daisy-chain or radial mode.

 The resistor pack must remain installed on the last drive in a chain.

 The resistor pack must remain installed on all radially-selected
 drives.


 Shock and vibrations
 --------------------
 All shock and vibration specifications assume that the drive is moun-
 ted in an approved orientation with the input levels at the drive
 mounting screws.


 Read/Write Head Park Zone
 -------------------------
 ST213/ST225/ST238R
 The read/write heads may be parked by issuing a seek to any cylinder
 between 615-670

 ST225R/ST250R
 The read/write heads may be parked by issuing a seek to any cylinder
 between 667-670

 At power-on the drive will recalibrate to Track 0. If the heads are
 parked while power is still applied, any step pulse will cause the
 unit to recalibrate to Track 0.


 FCC Verification
 ----------------
 These drives are devices which are intended to be contained solely
 within a personal computer or similar enclosure and not attached to
 an external device. As such, they are considered to be subassemblies
 even when individually marketed to the customer. As a subassembly, no
 Federal Communications Commission certification of the device is re-
 quired.


 DC Power Requirements
 ---------------------
 Power may be applied or removed in any sequence without loss of data
 or damage the drive.


 Input Noise
 -----------
 Maximum permitted input noise ripple: 100 mV (peak-to-peak)
 Maximum permitted input noise: 20 MHz.
 Ripple measured at the host system power supply across an equivalent
 8  resistive load on the +12 V line and an equivalent 3  load on the
 +5 V line.


 DC-Unsafe
 ---------
 A DC-unsafe condition is defined as DC voltage input to the drive
 outside the specified tolerances. This condition will cause a micro-
 processor reset.
 This will prohibit writing, but will not directly cause a Write Fault


 Handling and Static-Discharge Precautions
 -----------------------------------------
 After unpacking, and prior to system integration, the drive may be
 exposed to potential handling and ESD hazard. Do not touch the drive
 connectors or board components or without observing static-discharge
 preferred. Handle the drive by the frame only. Always rest the drive
 on a padded surface until it is mounted in the host system.


 Auto-Truncation
 ---------------
 The drive will enter the auto-truncation mode if the controller
 issues an excessive number of step pulses, which would place the
 read/write heads outward beyond Track 0 or inward beyond the
 maximum data cylinder.

 With auto-truncation active, the drive will ignore additional pulses,
 take control of the actuator, and recalibrate the heads to Track 0.

 Caution: If the controller is still issuing slow-step pulses after
          the drive issues Seek Complete from auto-truncation mode,
          the drive will either reenter auto-truncation mode with
          Direction In true.


 Precompensation
 ---------------
 For optimum performance, precompensation is recommended for the ST213
 and ST225 on tracks 300 through 614. Twelve nsec. is recommended for
 both early and late bits.

 Some controllers provide a default precompensation setting from cyl-
 inder 128 to 256. The ST213 and ST225 will perform satisfactorily at
 these settings.



**********************************************************************
                      F   E   A   T   U   R   E  S
**********************************************************************
SEAGATE  ST213/ST225/ST225R/ST238R/ST250R  PRODUCT MANUAL 36025-003

 Media Defects
 -------------
 A media defect is a read error when the data, which has been
 correctly written, cannot be recovered within 16 retries.
 A printout will be provided with each drive shipped listing the
 location of any defect by head, cylinder, sector and byte. The defect
 map will specify the number of bytes from index. For MFM this will be
 based on 1.6  sec./byte. RLL encoding is based on 1.056  sec./byte.
 Some drives will have the defect map fixed to the drive top cover.

 ST213  There will be no more than 11 defects total per drive.
        Cylinders 0, 1, 2 and 3 will be free of defects.

 ST225  There will be no more than 21 defects total per drive.
 ST225R Cylinders 0, 1, 2 and 3 will be free of defects.

 ST238R There will be no more than 33 defects total per drive.
        Cylinders 0, 1, and 2 will be free of defects.

 ST250R There will be no more than 42 defects total per drive.
        Cylinders 0, 1, and 2 will be free of defects.


 Access Time Definition and Timing
 ---------------------------------
 Access time is defined as the time from leading edge of the last
 step pulse received to Seek Complete (including setting). The step
 pulse period must be 5-200  sec.

                                          | ST213  |        |
                                          | ST225  | ST225R |
                                          | ST238R | ST250R |
        ----------------------------------+--------+--------+
        Track-to-Track         msec.      |  20    |  20    |
                       Average msec. typ. |  65    |  70    |
                       Average msec. max. | 150    | 165    |
        Latency                msec. avg. |   8.33 |  10    |
        ----------------------------------+--------+--------+


 Bit Jitter
 ----------
 Bit jitter reduction determines the relationship between the leading
 edge of read data and the center of the data window.
 The data separator must provide at least -40dB of bit jitter
 reduction at 2F with an offset of less than 1.5 nsec. shift from the
 center of the data window.


 UL/CSA Listing
 --------------
 The drive family is listed in accordance with UL 478 and CSA
 C22.2 (0-M1982), and meets all applicable sections if IEC 380 and
 VDE 0806/08.81, as tested by TUV-Rheinland, North America.

 Reliability
 -----------
 MTBF           100,000 Power-on hours
 PM:            Not required
 MTTR:          30 Minutes
 Service life:  5 Years



**********************************************************************
                      G   E   N   E   R   A   L
**********************************************************************
SEAGATE   SUPPORT SERVICES

 Seagate Technology
 ------------------
 Technical Support Services
 If you need assistance installing your drive, consult your dealer.
 Dealers are familiar with their unique system configurations and can
 help you with system conflicts and other technical issues. If you
 need additional assistance with your Seagate(r) drive or other
 Seagate products, use one of the Seagate technical support services
 listed below.

 SeaFONE at 1-800-SEAGATE (1-800-732-4283)
 Seagate's 800 number allows toll-free access to automated self-help
 services, providing answers to commonly asked questions,
 troubleshooting tips and specifications for disc drives and tape
 drives. This service is available 24 hours daily and requires a
 touch-tone phone. If you need to speak to a technical support
 engineer, dial this number and listen to the options for technical
 support. (International callers can also reach this automated
 self-help service by dialing 408-456-4496).


 Seagate Technology online services
 Using a modem, you can obtain troubleshooting tips, free utility
 programs, drive specifications and jumper settings for Seagate's
 entire product line. You can also download software for installing
 and analyzing your drive.

 SeaNET
 You can obtain technical information on Seagate drives, Seagate
 software and much more over the Internet from Seagate's World Wide
 Web home page (http://www.seagate.com) or Seagate's ftp server
 (ftp://ftp.seagate.com).

 You may also send E-mail with your questions to DiscSupport@
 Seagate.com or TapeSupport@Seagate.com.


 SeaBOARD
 SeaBOARD is a computer bulletin board system (BBS) that contains
 information about Seagate's disc and tape drive products and is
 available 24 hours daily. Set your communications software to eight
 data bits, no parity and one stop bit (8-N-1). SeaBOARD phone numbers
 are listed in the following table.

 BBS Location           Modem number
 United States      Disc: 408-434-1080; Tape: 408-456-4415
 England            44-1628-478011
 France                         33 1-48 25 35 95
 Germany            49-89-140-9331
 Singapore          65-292-6973
 Thailand           662-531-8111
 Australia          61-2-9756-2359
 Taiwan             886-2-719-6075

 Seagate CompuServe forum
 Online technical support for Seagate products is available on
 CompuServe. To access our technical support forum, type go seagate.
 This forum provides information similar to that found on SeaBOARD.
 In addition, you can type questions or browse through previous
 questions and answers on the forum messages.

 Seagate Technology FAX services
 SeaFAX
 You can use a touch-tone telephone to access Seagate's automated FAX
 system to receive technical support information by return FAX. This
 service is available 24 hours daily.
 Location               Telephone number
 United States          1-800-SEAGATE or 408-456-4496
 England                44-1628-894084
 Australia              61-2-9756-5170

 Seagate technical support FAX
 You can FAX questions or comments to technical support specialists 24
 hours daily. Responses are sent during business hours.
 Location               FAX number
 United States          408-944-9120
 England                        44-1628-890660
 France                 33 1-46 04 42 50
 Germany                        49-89-1430-5100
 Australia              61-2-9725-4052
 Singapore              65-293-4722
 Hong Kong              852-2368 7173
 Taiwan                 886-2-715-2923
 Korea                          82-2-556-7294/4251


 Seagate technical support
 You can talk to a technical support specialist during business hours
 Monday through Friday for one-on-one technical help.  Before calling,
 note your system configuration and drive model number (STxxxx). There
 are several technical support phone numbers available for various
 Seagate products.

 Location          Telephone  number
 United States Please dial 1-800-SEAGATE for the specific product
               telephone number.
               (6:00 A.M. to 11:15 A.M., 12:30 P.M. to 5:00 P.M.,
               Pacific time, M-F)
 England       44-1628-894083 (10:00 A.M. to 1:00 P.M., 2:00 P.M. to
               5:00 P.M., M-F)
 France        33 1-41 86 10 86 (9:30 A.M. to 12:30 P.M., 2:00
               P.M. to 5:00 P.M., M-F)
 Germany       Disc: 49-89-140-9332; (9:30 A.M. to 12:30 P.M., 2:00
               P.M. to 4:00 P.M., M-F)
               Tape: 49-89-140-9333
 Australia     61-2-9725-3366 (9:00 A.M. to 5:00 P.M., M-F)
 Singapore     65-290-3998 (9:00 A.M. to 12:00 P.M., 2:00
               P.M. to 5:00 P.M., M-F)
 Hong Kong     852-2368 9918
 Taiwan        886-2-514-2237
 Korea         82-2-556-8241


 SeaTDD 408-944-9121
 Using a telecommunications device for the deaf (TDD), you can send
 questions or comments 24 hours daily and exchange messages with a
 technical support specialist between 6:00 A.M. to 11:15 A.M. and
 12:30 P.M. to 5:00 P.M. (Pacific time) Monday through Friday.


 Customer Service Centers
 Seagate direct OEM, Distribution, System Integrator and Retail
 customers should contact your Seagate Service Representative for
 warranty information.  Other customers contact your place of
 purchase.  Seagate offers comprehensive customer support for all
 Seagate drives.  Seagate customer service centers are the only
 facilities authorized to service Seagate drives. These services are
 available worldwide.

 Location                       Telephone number                FAX number
 United States          1-800-468-3472;                 405-949-6740
 Other Americas
 (Canada & Brazil)      405-949-6706;               405-949-6738
 Mexico                         525-546-6965;                   525-546-4888
 Europe, Middle
 East & Africa          31-2065-43300;              31-2065-34320
 Asia Pacific &
 Australia              65-485-3595;                    65-485-4980
 Japan                          81-3-5462-2904;                 81-3-3462-2979


 Seagate, Seagate Technology and the Seagate logo are registered
 trademarks of Seagate Technology, Inc. SeaFAX, SeaFONE, SeaBOARD,
 SeaTDD, SeaNET, Medalist and DiscWizard are either trademarks or
 registered trademarks of Seagate Technology, Inc. or one of its
 subsidiaries. All other trademarks or registered trademarks are the
 property of their respective owners.