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                            (C)opyright 1991



ST-1480A AT Interface

                    J5 Drive ID Select and             J6 (located on side
                    Configuration Select Header        near rear)
                           
                                                                o o1 (front)
40-pin I/O Cable Connector                               +5v ---o o
  1             o o o o o1                 
J4::::::::::::::::::  /\ o o o o o                    
 2ͳ 0 0 0 0 EDCBA       Remote LED Reserved
 (pin 20 missing for     5GG12 (see below)      Connection   Jumper
  keying purposes)         DC Power                                 Position


J5
JUMPER | FUNCTION:
A       REFSIG: This location provides a port for external connection
of the synchronized spindle reference signal (pin-1) and ground
(pin-2).  It is also available on J4 pin-28 if the factory jumper is
installed.  The drive will self-determine if it is a master of slave
for spindle synchronization.

B       HOST SLV/ACT: When this shunt is installed, -SLAVE PRESENT is
applied to J4 pin-39 for systems that require this signal from the
Slave drive. If jumper "B" is installed, then jumper "E" must not be
installed.

C       MASTER: When this shunt is installed, the drive is configured
as the Master.  When not installed, the drive is a Slave.

D       SLAVE PRESENT: When installed, this shunt indicates to the
Master drive that a Slave is present.  This shunt must be installed on
the Master drive in a two-drive system.

E       ACTIVE: When this shunt is installed, DASP- is made present on
J4 pin-39. If "E" is installed, then "B" must not be installed.


                              ST - 1480A

       UNFORMATTED CAPACITY (MB) ________________492
       FORMATTED CAPACITY (xx SECTORS) (MB) _____426
       AVERAGE SECTORS PER TRACK ________________62 (rounded down)
       ACTUATOR TYPE ____________________________VOICE COIL
       TRACKS ___________________________________13,302
       CYLINDERS ________________________________1474
       HEADS ____________________________________9
       DISCS ____________________________________5
       MEDIA TYPE _______________________________THIN FILM
       RECORDING METHOD _________________________ARLL 1,7 (ZBR)
       INTERNAL TRANSFER RATE (mbits/sec) _______17 to 25
       SPINDLE SPEED (RPM) ______________________4,412
       BUFFER ___________________________________64 Kbyte
         Read Look-Ahead, Non-Adaptive,
         Multi-Segmented Cache
       INTERFACE ________________________________AT
       TPI (TRACKS PER INCH) ____________________1760
       BPI (BITS PER INCH) ______________________
       AVERAGE ACCESS (ms) ______________________14
       SINGLE TRACK SEEK (ms) ___________________2.5
       MTBF (power-on hours) ____________________150,000
       POWER REQUIREMENTS: +12V START-UP (amps) _2.5
                           +12V TYPICAL (amps) __0.7
                           +5V TYPICAL (amps) ___0.7
                           TYPICAL (watts) ______8
                           MAXIMUM (watts) ______15
       BUFFERED STEP PULSE RATE (micro sec) _____
       WRITE PRECOMP (cyl) ______________________N/A
       REDUCED WRITE CURRENT (cyl) ______________N/A
       LANDING ZONE (cyl)________________________AUTO PARK
       IBM AT DRIVE TYPE ________________________*

Possible translation:   895 cyl, 15 heads, 62 sectors = 426,163,200

Note: A "custom" or "user-definded" CMOS drivetype  may ask for a
numerical value for the Write Precompensation cylinder and for the
Landing Zone cylinder.  A basic rule-of-thumb for drive models that do
not require the old Write Precomp technique or a Landing Zone because
they are Auto-Parking is to add 1 to the cylinder value being used. As
an example: If cylinders equaled 820, then both Write Precomp and
Landing Zone would be entered as 821. Some BIOS will convert this to
65535 or -1, which are functionally equivalent to "none (not used)".

 * MAY REQUIRE FORMATTING AND PARTITIONING SOFTWARE.  ALSO, CHECK TO
SEE IF YOUR CMOS SETUP HAS A "CUSTOM" OR "USER DEFINABLE" DRIVE TYPE
AVAILABLE. (see below)

PHYSICAL/LOGICAL equivalent to NATIVE/TRANSLATION
ZBR = Zone Bit Recording = Variable sectors per track

Already low-level formatted at the factory.

Since a User-definable or Custom translation geometry may be used, it
is imperative that the values be written down and kept with your
permanent records for retrieval in the event of CMOS battery failure.

Seagate reserves the right to change, without notice, product
offerings or specifications. (4/12/91)
