previous page: Hard Drive: SEAGATE: ST4026 (1990) 21MB 5.25"/FH   MFM ST506
page up: Hard Drive Specs from SEAGATE
next page: Hard Drive: SEAGATE: ST4038 (1990) 31MB 5.25"/FH   MFM ST412

Hard Drive: SEAGATE: ST4038 (1987) 31MB 5.25"/FH MFM ST412

S T 4 0 3 8   ( 1 9 8 7 )    SEAGATE
NO MORE PRODUCED                                      Native|  Translation
Form                 5.25"/FH              Cylinders     733|     |     |
Capacity form/unform    31/   38 MB        Heads           5|     |     |
Seek time   / track  40.0/ 8.0 ms          Sector/track   17|     |     |
Controller           MFM / ST412           Precompensation   300
Cache/Buffer               KB              Landing Zone
Data transfer rate    0.625 MB/S int       Bytes/Sector      512
                      0.625 MB/S ext
Recording method     MFM                            operating  | non-operating
Supply voltage     5/12 V       Temperature *C        10 45    |    -40 60
Power: sleep              W     Humidity     %         8 80    |      5 90
       standby            W     Altitude    km    -0.305  3.048| -0.305  9.144
       idle          25.5 W     Shock        g        10       |     35
       seek          37.5 W     Rotation   RPM      3600
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit
                                MTBF         h      12000
                                Warranty Month
Lift/Lock/Park     YES          Certificates     CSA,FCC,IEC380,TUV,UL478,VDE 


SEAGATE ST4038/4051 PRODUCT MANUAL 36038-001, REV. A, 2/5/87

  |                                                         |XX
  |                                *JP1                     |XX J2
  |                                                         |XX
  |                                                         |XX
  |                                                         1-+ J10
  |                                                         | |xx/
  |                                                         |J9 Frame
  |                                                         +-+
  |                                                         |XX
  |                                                         |XX J1
  |                                      JP2++  +---------+ |XX
  |                                         1+  +---------1 |XX
  |                                             Terminator  |XX
  |                                                         |XX
  |                                                         |  1
  |                                                         |XX J3
  |                                                         |XX Power
  +---------------------------------------------------------+  1


SEAGATE ST4026/4038/4051 PRODUCT MANUAL 36038-001, REV. A, 2/5/87

Jumper Setting

The ST4038/4051 may be configured for specific system requirements.

Drive Configuration Shunt: J9
J9 is a right-angle shunt located midway between the J1 and J2
connectors. The ST4026 has an eight-pin shunt. The ST4038/4051 have
a sixteen-pin shunt. Use the provided shorting block(s) to enable the
Drive Select line and any options.

Drive Select
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.

Pins 1-2 shorted enables DRIVE SELECT 1
Pins 3-4 shorted enables DRIVE SELECT 2
Pins 5-6 shorted enables DRIVE SELECT 3
Pins 7-8 shorted enables DRIVE SELECT 4

      ST4026 J9                 ST4038/4051 J9
      ---------                 --------------

      +-------- DS4                 +-------- DS4
      | +------ DS3                 | +------ DS3
      | | +---- DS2                 | | +---- DS2
      | | | +-- DS1                 | | | +-- DS1
     +-+-+-+1+            15-+-+-+-+-+-+-+-+
     +-+-+-+-+             +-+-+-+-+-+-+-+-+
     +8+-+-+-+             +-+-+-+-+-+-+-+-2
                            | | | +---------- NOT CONNECTED
                            | | +------------ WRITE FAULT
                            | +-------------- RECOVERY MODE
                            +---------------- RADIAL

Daisy-Chain/Radial Drive Configurations
The ST4038/4051 can be configured in either a Daisy-Chain or Radial
mode. The ST4026 can be configured in a Daisy-Chain mode only.

In a Daisy-Chain configuration, the last drive in a chain must have
the resistor termination pack installed.

The radial option on the ST4038/4051 is enabled by shorting pins 15
and 16 at J9. The resistor termination packs must remain installed on
any radially configured drive.

Write Fault Latch options: JP2 and J9
The ST4038/4051 allow the user to configure the Write Fault reset to
specific system requirements. These drives have provisions for pins
to be installed at JP2 to enable the desired options.

As shipped, there may be a trace between pins 2 and 3 on JP2. This
trace must be cut to allow use of the options requiring pins 1 and 2.

JP2 Unlatched: Write Fault will be cleared when write gate is false.
A Write Fault will only occur when write gate is True.

JP2 Latched: This option will maintain Write Fault True after write
gate goes false and is recommended for controllers that do not edge-
detect Write Fault.

The latched operation has two configurations which are provided at
the J9 shunt, pins 11-12.

 1. No jumper at J9: The Write Fault signal can only be cleared by a
    power-on/off cycle. Use of this option in conjunction with the DC-
    Unsafe option is not recommended.

 2. Pins 11-12 shorted at J9: The Write Fault signal can be cleared by
    de-selecting the drive. When the drive is deselected, and the
    fault condition is corrected, the Write Fault signal will be

DC-Unsafe Option: JP1
There are provisions on the ST4038/4051 for pins to be installed to
enable this option. When shorted, a DC-Unsafe condition will cause a
Write Fault to be sent to the interface.


SEAGATE ST4026/4038/4051 PRODUCT MANUAL 36038-001, REV. A, 2/5/87

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!

The ST4026/4038/4051 may be mounted horizontally with the Main
Control PC Board with the J1 and J2 connectors down or on either
side. Mounting vertically on either end is a prohibited orientation.

The drive should not b etilted front or back, in any position, by
more than 5*. For optimum performance the drive should be formatted
in the same orientation as it will be mounted in the host system.

Shock Mounting Recommendations
It is recommended that any external shock mounts between the drive
and the host frame b edesigned so that the composite system has a
vertical resonant frequency of 25 Hz or lower. A minimum clearance of
0.050 inches should be allowed around the entire perimeter of the
drive to allow for cooling airflow and moton during mechanical shock
or vibration.

Mounting Holes
4 on bottom, 2 on each side: 6-32 UNC-2B x .31 deep min.


SEAGATE ST4026/4038/4051 PRODUCT MANUAL 36038-001, REV. A, 2/5/87

This manual supports the ST4026/4038/4051 disk drives. It is a
consolidation of the ST4026, ST4038 and ST4051 Product Manuals, part
number 36011-001, 36012-001 and 36013-001, which are now out of

Shipping Zone
Upon power-down, the actuator will automatically position the read/
write heads over the shipping zone and carriage lock will engage. All
portions of the head/slider assembly will park inboard of the maximum
data cylinder. When power is applied the lock will automatically
disengage and the heads will recalibrate to Track 0.

Seek-Retry is an internally generated command implemented by the
drive to enhance seek performance.

If the drive detects an off-track condition, or the seek was not
completed, th edrive will recalibrate the heads to Track 0 and retry
the seek. All writing is inhibited during retry.

If the target is still not achieved, or the seek was not completed,
the drive will set Write Fault true, and Ready and Seek Complete
false. Write Fault will remain active until the condition that
caused the fault is corrected and the reset is completed.

The drive will enter the auto-truncation mode if the controller
issues an excessive number of step pulses, which would place the
read/wrie 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.

If the controller is still issuing Slow-Step pulses after the drive
issues Seek Complete from auto-truncation mode with Direction In
false, or step the remaining cylinders with Direction In true.

The ST4051 does not require precompensation.

 Precompensation is required for the ST4026/4038 on cylinders 300
 through the maximum data cylinder in order to achieve optimum
 performance. The optimum amount of precompensation is 12 nsec. for
 both early and late bits. The table below indicates the bit patterns
 and the direction to be compensated.
  |Previous |Sending|Next|Timing           |
  | X  |  0 |   1   |  1 |Write Data Late  |
  | X  |  1 |   1   |  0 |Write Data Early |
  | 1  |  0 |   0   |  0 |Write Clock Late |
  | 0  |  0 |   0   |  1 |Write Clock Early|
 An X denotes a don't care state

Bit Jitter
Bit jitter reduction determines the relationship between the leading
esge of read data and the center of the data window.

The specified read error rates are based on the following bit jitter
specifications: the data separator must provide at least -40 dB of
bit jitter reduction at 2F with an offset error of less than 1.5
nsec. shift from the center of the data window.

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 locations of any
defect by head, cylinder, sector and byte. It will also specify the
number of bytes from index.

There will be no more than thirty-two (32) defects total per drive.
Cylinder 0 will be free of defects.

There will be no more than thirty-six (36) defects total per drive.
Cylinder 0 will be free of defects.

There will be no more than forty (40) defects total per drive.
Cylinder 0 will be free of defects.

previous page: Hard Drive: SEAGATE: ST4026 (1990) 21MB 5.25"/FH   MFM ST506
page up: Hard Drive Specs from SEAGATE
next page: Hard Drive: SEAGATE: ST4038 (1990) 31MB 5.25"/FH   MFM ST412