S T 1 2 5 N - 1 SEAGATE
NO MORE PRODUCED Native| Translation
------+-----+-----+-----
Form 3.5"/HH Cylinders 407| | |
Capacity form/unform 22/ 25 MB Heads 4| | |
Seek time / track 28.0/ 8.0 ms Sector/track 26| | |
Controller SCSI1 SINGLE-ENDED Precompensation
Cache/Buffer KB Landing Zone
Data transfer rate 0.938 MB/S int Bytes/Sector 512
1.500 MB/S ext ASYNC
Recording method RLL 2/7 operating | non-operating
-------------+--------------
Supply voltage 5/12 V Temperature *C 10 50 | -40 60
Power: sleep W Humidity % 8 80 | 5 90
standby W Altitude km -0.305 3.050| -0.305 9.140
idle W Shock g 10 | 60
seek W Rotation RPM 3600
read/write 9.0 W Acoustic dBA 40
spin-up W ECC Bit 32
MTBF h 150000
Warranty Month
Lift/Lock/Park YES Certificates CSA,FCC,IEC435,TUV,UL478,VDE
**********************************************************************
L A Y O U T
**********************************************************************
SEAGATE ST125N/ST138N/ST157N PRODUCT MANUAL 36045-006, REV.F
+------------------------------------------------------++-+4
| || |2
| || |1
| || |NC
| +-+ |+-+P
| | | |XX SCSI
| 1+-+ |XX Interface
| Resistor +-+ |XX Connector
| Terminator | | |XX J1
| Packs 1+-+ |XX
| +-+ |XX
| | | |XX
| 1+-+ |X1
| |
| |XX Power
| |XX J3
+------------------------------------------------------+
**********************************************************************
J U M P E R S
**********************************************************************
SEAGATE ST125N/ST138N/ST157N PRODUCT MANUAL 36045-002, REV.D
Jumper setting
--------------
J2 SCSI Bus Adress and Parity Check
-------------------------------------
Select the desired SCSI ID with Jumpers. Install the optional
P-Jumper to enable Parity.
+-------+---------------+
|SCSI ID| P NC 4 2 1 | Each drive must have a distinct
+-------+---------------+ adress (SCSI ID) on the bus. SCSI ID 7
| 0 | o o o o o | is usually reserved for the SCSI host
| 1 | o o o o x | adapter.
| 2 | o o o x o |
| 3 | o o o x x | The microprocessor only reads the
| 4 | o o x o o | SCSI ID during the startup sequence.
| 5 | o o x o x | If the adress is changed while system
| 6 | o o x x o | power is on, the drive power must be
| 7 | o o x x x | removed and then reapplied for the
+-------+---------------+ changes to take effect.
| |
| +---- Not used
|
+------- Parity Bit Option
Some host systems require parity bit checking
Install the P-Jumper to enable Parity
50-Pin SCSI Connector Pin Assignments
-------------------------------------
Signal Pin No. Signal Pin No.
----------------------------------------
-DB(0) 2 Ground 28
-DB(1) 4 Ground 30
-DB(2) 6 -ATN 32
-DB(3) 8 Ground 34
-DB(4) 10 -BSY 36
-DB(5) 12 -ACK 38
-DB(6) 14 -RST 40
-DB(7) 16 -MSG 42
-DB(P) 18 -SEL 44
Ground 20 -C/D 46
Ground 22 -REQ 48
Ground 24 -I/O 50
Terminator 26
Power
Note: All odd pins, except pin-25 are connected to ground. Pin-25
is not connected.
J3 DC Power and pin connector assignments
-------------------------------------------
+------------+ 1 = + 12 VDC
| 1 2 3 4 | 2 = + 12 Volts return
+------------+ 3 = + 5 Volts return
4 = + 5 VDC
**********************************************************************
I N S T A L L
**********************************************************************
SEAGATE ST125N/ST138N/ST157N PRODUCT MANUAL 36045-006, REV.F
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 posi-
tion, 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.
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 Auto-Park
-------------------------
Upon power-down, the read/write heads automatically move to the ship-
ping zone. All portions of the Head/slider assembly park inboard of
the maximum data cylinder.
When power is applied, the heads will 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 authorization, verification or
certification of the device is required.
Disc format
-----------
The drives disc format is flexible and supports either 256, 512 or
1024 bytes/sector.
ST125N | ST138N | ST157N
----------------------------------+----------------+----------------
Bytes per Sector: 256 512 1.024 | 256 512 1.024 | 256 512 1.024
Sectors per Track: 44 26 13 | 44 26 13 | 44 26 13
Cylinders: 407 | 615 | 615
Read/Write heads: 4 | 4 | 6
Capacity (MByte): 18 21 21 | 27 32 32 | 41 49 48
Record interleave
-----------------
User-specific record interleaves are supported from 1:1 (sectors
occur sequentially on the disk) through the number of sectors per
track minus 1. This gives the user the ability to configure the drive
for maximum performance within the individual host operating environ-
ment.
Formatting and defect management
--------------------------------
Media defects are identified and recorded on the disc during the ma-
nufacturing process. This defect map is used during formatting and
enables the drive to bypass these defects. During the formatting
operation, the controller uses the sector-slip technique to reassign
defect sectors.
SCSI Interface
--------------
The embedded controller supports the SCSI interface as defined in the
ANSI X3T9.2/82-2 document. The interface hardware is capable of
transferring up to 12 Mbits/sec. using asynchronous data transfer.
Devices on the SCSI Interface are daisy-chained together using a
common cable. Both ends of the cable are terminated. All signals on
the interface are common between devices.
Termination resistor packs
--------------------------
The termination resistor packs must be present on devices at both
ends of the SCSI bus. All other devices should have the termination
resistors removed.
Termination resistors prevent signal reflections from the ends of the
SCSI bus, and assure proper bus timing.
DC Power specifications
-----------------------
Power may be applied or removed in any sequence without loss of data
or damage to the drive, except during a write operation. Typical
current and power specifications assume nominal voltages applied,
25*C ambient temperature, sea level and spindle rotating.
Voltage tolerance (incl. ripple): 5%
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.
Cable specification
-------------------
A 50-conductor flat cable or 25-conductor twisted pair cable is
required. The maximum cable length is 6 meters (19.7 ft). Each SCSI
bus connection may have a 0.1 meter (0.33 ft) maximum stub length.
The characteristic impedance for unshielded flat or twisted pair
ribbon cable should be 100 10%. A characteristic impedance greater
than 90 is preferred for shielded cables.
To minimize discontinuities and signal reflections it is desirable
to minimize the use of cables of different impedances in the same
bus.
Startup Drive Diagnostics
-------------------------
At power-on the drive will execute a series of diagnostic tests. Any
failure will be indicated by a series of LED (front panel) flashes.
The first failure will be preserved. The drive is ready to read/write
if no error codes are received within 22 seconds.
+-------+---------------------------------------------------------+
|Flashes|Failures codes |
+-------+---------------------------------------------------------+
| 1 |Microprocessor/Internal Memory Test |
+-------+---------------------------------------------------------+
| 2 |Microprocessor ROM Checksum Test |
+-------+---------------------------------------------------------+
| 3 |Controller Chip Test |
+-------+---------------------------------------------------------+
| 4 |Controller Program RAM Test |
+-------+---------------------------------------------------------+
| 5 |Data Buffer RAM Test |
+-------+---------------------------------------------------------+
| 6 |Spindle Speed Test |
| | If the drive is unable to reach and maintaine correct |
| | spindle speed |
+-------+---------------------------------------------------------+
| 8 |Read Operating System Microcode From Drive |
| | If the controller is unable to read the operating system|
| | from the drive |
+-------+---------------------------------------------------------+
| 9 |Read Operating System Microcode From Drive |
| | If the controller reads the operating system records, |
| | but dertermines that they are invalid. |
+-------+---------------------------------------------------------+
Offline Self-test Routines
--------------------------
This product family supports a self-test routine that Seagate recom-
mends for incoming inspection. This test may be run after the unit
has successfully passed the power-on diagnostics.
To enable the test, short the following pins to ground at the SCSI
connector: 2, 12, 16 and 32.
The self test has three parts. They will cycle in order until power
or a ground jumper is removed, or until ten complete passes.
The LED will remain ON during the test and will turn OFF if an error
is detected or a jumper is removed. The LED will flash continuously
if 10 passes are completed without error.
SCSI Interface Drive Geometry
-----------------------------
The SCSI interface handles both drive geometry and defect management
internally. In AT systems a drive type of zero, or the "no drive in-
stalled" option is selected for systems with SCSI drvies.
Set the SCSI Address
--------------------
If you are installing one drive, the suggested ID is 0 (no jumper in-
stalled). A second physical drive may be set at any ID (typically
Address number 1). These SCSI ID numbers cannot conflict with any
other devices on the SCSI bus. Each device must have a discrete SCSI
ID. SCSI ID address 7 is typically used by the SCSI Host Adapter.
Drive Termination Resistor Packs
--------------------------------
If you are installing one drive, leave the resistor packs installed.
If you are installing multiple drives, remove the resistor packs from
all drives except the last drive connected to the end of the cable.
Drive formatting
----------------
All Seagate SCSI interfaces drives are low-level formatted at the
factory. You may wish to low-level format the drive to optimize its
performance for your system. Consult the controller documentation for
information on low-level formatting.
Partitioning and high-level formatting can be done through DOS.
**********************************************************************
F E A T U R E S
**********************************************************************
SEAGATE ST125N/ST138N/ST157N PRODUCT MANUAL 36045-006, REV.F
Formating and Defect Management
-------------------------------
Because Seagate SCSI interface drives have the controller onboard,
bad sectors are mapped out and become transparent to the user; this
allows Seagate to specify "guaranteed megabytes" for SCSI drives and
eliminates the requirement for a media defect specification.
Error Recovery
--------------
The controller provides error recovery routines which are necessary
to assure data integrity. These techniques include ECC, seek-retry,
read-retry, head-offset and defect management. To assure a high de-
gree of data reliability, the controller utilizesa 32-bit error
checking and correction polynominal.
SCSI bus drivers/receivers
--------------------------
The drives use open collector drivers. All signals are terminated
with 220 to +5 VDC (nominal) and 330 to ground. For these
measurements, SCSI bus termination is assumed to be external to the
drive. A typical drive is supplied with the resistor termination
packs installed.
Signals driven by the drive have the following output
characteristics, when measured at the drive connector:
Signal true: 0.0 VDC to 0.4 VDC
Maximum total input load: 48 mAmps (sinking) @ 0.5 VDC
Signal false: 2.5 VDC to 5.25 VDC
Signals received by the drive have the following input
characteristics, when measured at the drive connector:
Signal true: 0.0 VDC to 0.8 VDC
Maximum total input load: -0.4 mAmps (sinking) @ 0.4 VDC
Signal false: 0.2 VDC
DC Power Specifications
-----------------------
Power may be applied or removed in any sequence without loss of data
or damage to the drive.
Recording Method
----------------
The drives are designed to operate with the SCSI interface
with Run Length Limited (2,7) encoding at 7.5 Mbits/sec. data
transfer rate.
Bit Jitter
----------
Bit jitter reduction determines the relationship between the leading
edge 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 -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 ST157 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.
**********************************************************************
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.