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Native| Translation
------+-----+-----+-----
Form 3.5"/HH Cylinders 2626| | |
Capacity form/unform 2148/ 2537 MB Heads 19| | |
Seek time / track 9.0/ 2.0 ms Sector/track | | |
Controller SCSI2 DI/WI/FAST Precompensation
Cache/Buffer 256 KB SEGMENTED Landing Zone
Data transfer rate 4.000 MB/S int Bytes/Sector 512
20.000 MB/S ext SYNC
Recording method RLL 1/7 operating | non-operating
-------------+--------------
Supply voltage 5/12 V Temperature *C 5 50 | -40 70
Power: sleep W Humidity % 8 80 | 5 95
standby W Altitude km -0.305 3.048| -0.305 12.192
idle 9.0 W Shock g 10 | 60
seek W Rotation RPM 5411
read/write W Acoustic dBA
spin-up W ECC Bit REED SOLOMON
MTBF h 500000
Warranty Month 60
Lift/Lock/Park YES Certificates CSA,EN60950,FCC,UL1950,VDE
**********************************************************************
L A Y O U T
**********************************************************************
SEAGATE ST12400W/WD PRODUCT MANUAL 77767457 REV. C 17/3/95
+---------------------------------------------------------+
| |XX1
| |XXPower
| |1-+
| || J5
++LED || |
++ |+-+
| |+1+
| ||X|I/O
| ||X|
| ||X|
| ||X|J1
| ||X|
|+-+ ||X|
|| |J6 ||X|
|+-1 8--------1 ||X|
| +--------+J2 |+-+
+---------------------------------------------------------+
**********************************************************************
J U M P E R S
**********************************************************************
SEAGATE ST12400W/WD PRODUCT MANUAL 77767457 REV. C 17/3/95
Jumper Setting
==============
REAR VIEW +------ 5V
| +---- GND
(TOP) | | +-- GND
34 1 1 | | | + 12V
+---------------------+ +-J5---+ +-------+
----+|||||||||||||||||||||+--+::::::+-+O O O O+-
+---------------------+ +------+ +-------+
68pin I/O Cable |||||| Power SCSI ID = 0 (none)
Connection |||||+----------- SCSI ID = 1
||||+------------ SCSI ID = 2
|||+---------+--- SCSI ID = 4 or pin-6
||| +--- REFIND+
||+-------------- SCSI ID = 8
|+--------------- pin-10 GND
+---------------- pin-11 +5V
J5 SCSI ID
-----------
+----------+-------------------------------+
| SCSI ID | Jumper Location |
| | PINS |
| | 7-8 | 5-6 | 3-4 | 1-2 |
+----------+-------+-------+-------+-------+
| 0 | OPEN | OPEN | OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 1 | OPEN | OPEN | OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 2 | OPEN | OPEN | CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 3 | OPEN | OPEN | CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
| 4 | OPEN | CLOSED| OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 5 | OPEN | CLOSED| OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 6 | OPEN | CLOSED| CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 7 | OPEN | CLOSED| CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
| 8 | CLOSED| OPEN | OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 9 | CLOSED| OPEN | OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 10 | CLOSED| OPEN | CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 11 | CLOSED| OPEN | CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
| 12 | CLOSED| CLOSED| OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 13 | CLOSED| CLOSED| OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 14 | CLOSED| CLOSED| CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 15 | CLOSED| CLOSED| CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
RIGHT SIDE VIEW
+-J1 TOP (HDA)
|X+------------+--------+-----PWA--------------------Front of drive
+-+ |12345678|J2
+--------+
+Terminator PWR -+||||||+- RESERVED
+Terminator PWR --+||||+-- Start Delay (12 secs * ID)
| Enable T-Res ---+||+--- Motor Start
| Parity Enable ----++---- Write Protect
|
|
Terminator Power-source Table
-----------------------------
1 2 1 2 1 2
+---- +---- +----
|X o |o X |o o
|X o |o X |xxx
+------ +------ +-------
Drive Supplies Drive Supplies Bus Supplies
Bus Own Drive (Position A)
FRONT VIEW J6
TOP (HDA) +-----1+
-------PWA--------------------------------+::::::+---
++ +------+ SCSI ID = 0 none
++LED pin-11 +5V --+||||+-- SCSI ID = 1
pin-10 GND ---+||+--- SCSI ID = 2
SCSI ID = 8 or -+--++--+- SCSI ID = 4 or
pin-8 BUSY -+ +- pin-6 REFIND+
NOTE
If these ID jumper are used, the ID jumpers J5 ARE NOT USED!!!!!
J6 SCSI ID
-----------
+----------+-------------------------------+
| SCSI ID | Jumper Location |
| | PINS |
| | 7-8 | 5-6 | 3-4 | 1-2 |
+----------+-------+-------+-------+-------+
| 0 | OPEN | OPEN | OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 1 | OPEN | OPEN | OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 2 | OPEN | OPEN | CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 3 | OPEN | OPEN | CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
| 4 | OPEN | CLOSED| OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 5 | OPEN | CLOSED| OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 6 | OPEN | CLOSED| CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 7 | OPEN | CLOSED| CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
| 8 | CLOSED| OPEN | OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 9 | CLOSED| OPEN | OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 10 | CLOSED| OPEN | CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 11 | CLOSED| OPEN | CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
| 12 | CLOSED| CLOSED| OPEN | OPEN |
+----------+-------+-------+-------+-------+
| 13 | CLOSED| CLOSED| OPEN | CLOSED|
+----------+-------+-------+-------+-------+
| 14 | CLOSED| CLOSED| CLOSED| OPEN |
+----------+-------+-------+-------+-------+
| 15 | CLOSED| CLOSED| CLOSED| CLOSED|
+----------+-------+-------+-------+-------+
Drive ID/option select header
-----------------------------
Both J1-auxiliary and J6 have pins for selecting drive ID and for
connecting the synchronized spindle cable and the remote LED cable.
Only one or the other should be used, although using both at the same
time would not damage the drive. The notes ([1]-[9]) following the
figures describe the functions of the various jumper positions on the
three connectors J2, J1-auxiliary and J6. Sug-gested part number for
the unusual J2 jumper is Molex 52747-0211 (Seagate P/N 77679052).
Notes explaining the functions of the various jumpers on jumper
header connectors J2, J1-auxiliary and J6 are given below in
left to right order of jumper position. The term "default"
means as standard OEM units are configured when shipped from
factory. "Off" means no jumper is installed; "On" means a jumper
is installed. "Off" or "On" underlined is factory default
condition.
The PCB on "WC" models does not have connector J1-auxiliary, but
has a single 80 pin combined SCSI I/O and DC power connector
instead of the pictured 68 pin SCSI I/O, J1-auxiliary and 4 pin
DC power connectors. Included among the 80 pins are the SCSI ID,
Motor Start and Delayed Motor Start select functions, and the
synchronous spindle master sync signal (REFIND+) and the remote
LED signals. Do not use J2 and J6 for these five functions if the
host uses the ones included in the 80 pin connector.
The drive uses headers J6 or J1-auxiliary for drive ID
determination only during a 250 ms initialization period
following power-on or after a drive reset. During this
initialization period, the drive control logic connects pins
2, 4, 6 and 8 to ground and checks the logic state of pins 1,
3, 5 and 7. A ground on a pin 1, 3, 5, 7 indicates an asserted
low state, while an open circuit, high impedance or +5 V
indicates a negated high state. The drive user can install jumper
plugs to connect pins 2, 4, 6 and 8 to pins 1, 3, 5 and 7,
respectively, in the desired ID pattern.
The drive only connects ground to pins 2, 4, 6 and 8 during the
250 ms initialization period. The user may install a cable on J6
or J1-auxiliary in order to connect the drive ID pattern to pins
1, 3, 5 and 7 through some external switching circuit. The drive
ID should be applied for at least the 250 ms period. During the
remaining operational time of the drive, the drive does not poll
pins 1, 3, 5 and 7 for drive ID, unless a reset occurs. See Note
[4] for information on the use of pins 2, 4, 6 and 8 during
non-initialization periods.
During non-initialization periods when the drive does not connect
ground to pins 2, 4, 6 and 8, these pins can be used for
non-drive ID functions. Therefore, instead of using jumper plugs
on J1-auxiliary to estab-lish drive ID, a cable can be connected
to either J6 or J1-auxiliary to connect the drive activity (busy)
LED and make parallel connections of pins 1, 3, 5 and 7 to
external drive ID switching or jumpering circuits. If connected
pin 8 lights the drive busy LED when the drive connects
ground to that pin. Connection can be made to pin 6 to conduct
the synchronized spindle reference signal, REFIND+ to the host
and to other Seagate disk drives. Spindle synchronization
typically works effectively only if all drives connected through
pin 6 are identical in make and model. During the 250 ms
initialization period the LED lights and the REFIND+ signal goes
to 0 V.
J6 can be used to establish drive ID using jumpers (or remote ID
selector) and a cable can be plugged simultaneously to
J1-auxiliary to connect to the drive activity (busy) LED and the
synchronized spindle signal SSP. The vice-versa arrangement is
possible also. Two separate drive ID determining locations should
not be used, however.
These jumper positions apply to model ST12400W only.
This jumper position applies to models ST12400W and ST12400WD
only.
These signals are also on J1. The J2 and J6 jumper headers
are not used if the J1 signals are used.
Drive is probably shipped with this jumper installed, but it
should be removed if the system uses REFIND+ on J1-37.
These jumper positions do not apply to "WC" models.
J2 Jumper
Installation |Jumper Function Description
-------------+----------------------------------------------------
RES |
Off/On |Reserved. Default is no jumper installed.
-------------+----------------------------------------------------
DS ME |
Off Off |Spindle starts immediately after power up - Default
|setting.
-------------+----------------------------------------------------
Off On |Drive spindle does not start until Start Unit command
|received from host.
-------------+----------------------------------------------------
On Off |Spindle Startup is delayed by SCSI ID times 12 seconds
|after power is applied, i.e., drive 0 spindle starts
|immediately when DC power connected, drive 1 starts
|after 12 second delay, drive 2 starts after 24 second
|delay, etc.
-------------+----------------------------------------------------
On On |Drive spindle starts when Start Unit command received
|from host. Delayed start feature is overridden and does
|not apply when ME jumper is installed.
|
-------------+----------------------------------------------------
WP |
On |Entire drive is write protected.
-------------+----------------------------------------------------
Off |Drive is not write protected. Default is no WP jumper
|installed.
|
PE |
On |Parity checking and parity error reporting by the drive
|is enabled. Default is PE jumper installed.
-------------+----------------------------------------------------
Off |Drive does not report result of parity checking to
|host.
J2 Jumper
Installation Jumper Function Description
TE (ST12400W only)
On With the jumper installed, the On-board (non-removable)
terminator circuits are enabled (connected to the I/O
lines). Default is jumper installed.
Off Terminator circuits not connected to I/O lines.
TP TP
Off Off No terminator power is connected to drive terminators
or SCSI bus I/O pin 26.
On Off Drive supplies its own terminator power only. Jumper on
this position is factory default.
Off On Drive supplies power to I/O pin 26 of SCSI bus; none to
internal terminators. When drives have differential I/O
circuits, a jumper on the right TP position may be
needed to power external terminators (see system
documentation). The ST12400WD drive has differential
I/O circuits which have no terminator circuits on the
drive. The ST12400WC drive has no provisions for
terminators and no provisions for terminator power in
the 80 pin I/O connector. The TP jumpers do not apply
to model ST12400WC.
On On Drive supplies terminator power to itself (internal
connection) and to I/O pin 26 of SCSI bus. This is a
legal jumper setting.
TP Position A
On This horizontally positioned jumper across the two
TP positions nearest PCB edge, connects terminator
power from SCSI bus I/O pin 26 to the drive's internal
terminators (for Model ST12400W only).
Off See above explanations for TP jumpers.
J1-Auxiliary,
J6 Jumper
Installation Jumper Function Description
A3 ,A2 ,A1 ,A0 Drive ID on SCSI Bus (J1-auxiliary or J6 may be
used as the ID circuits are wired in parallel). The
drive ID is binary coded positionwise i.e., jumper in
position A3 is drive ID 8, A2 is drive ID 4, position
A1 is ID 2, position A0 is ID 1 and no jumpers is ID
0. Default is ID = 0. Both J1- auxiliary and J6 should
not be used at the same time, because at some future
time when the ID is changed the user could fail to
configure both J1-auxiliary and J6 the same. Model
ST12400WC does not have J1-auxiliary.
SSP
Used only as a cable connection for the reference index signal
(REFIND+) (J1-6A and J6 Pin 6, bottom) for sync spindle feature.
J1-10A or J6-10 provides ground. When no cable is connected, no
jumpers should be installed. Factory default is no jumper installed.
If a jumper is installed between pins 5 and 6 it will erroneously
enable Drive ID bit A2.
Synchronized spindles interface
-------------------------------
The Synchronized Spindles Interface (SSI) allows several drives
operating from the same host to operate their spindles at a
synchronized rotational rate. Spindle synchronization typically works
effectively only if all drives connected to the REFIND+ signal are
identical in make and model.
Electrical description
----------------------
The electrical interface consists of one digital TTL reference index
signal and ground. The reference index signal (REFIND+) is an output
if the drive is configured as a master and is an input otherwise. The
reference index signal is connected from drive to drive in a
daisychain fashion.
Termination
-----------
The reference index signal (REFIND+) is terminated with a 2K ohm
resistor. Each drive has a termination resistor located on the Main
PCB. The terminator resistor is not removable and is always in the
circuit.
Physical interface
------------------
They are 12 pin, 6 jumper position gold header type connectors. Pins
6 and 10 are used for connecting the Reference Index signal from
drive to drive. Pin 6 is REFIND+ and Pin 10 is ground. Either
J1-auxiliary or J6 may be used. On "WC" models REFIND+ is J6-6 and on
J1-37.
**********************************************************************
I N S T A L L
**********************************************************************
SEAGATE ST12400W/WD/WC PRODUCT MANUAL 77767457 REV. C 17/03/1995
Notes on installation
=====================
Installation direction
----------------------
horizontally vertically
+-----------------+ +--+ +--+
| | | +-----+ +-----+ |
| | | | | | | |
+-+-----------------+-+ | | | | | |
+---------------------+ | | | | | |
| | | | | |
| | | | | |
+---------------------+ | +-----+ +-----+ |
+-+-----------------+-+ +--+ +--+
| |
| |
+-----------------+
The drive will operate in all axis (6 directions).
Installation
------------
The drive is designed, manufactured, and tested with a "Plug in and
Play" installation philosophy. This philosophy minimizes the
requirements for highly trained personnel to integrate the drive
into the OEM's system, whether in a factory or field environment.
The drive has been low level formatted at the factory and need not be
reformatted.
Service tools
-------------
No special tools are required for site installation or recommended
for site maintenance. The depot repair philosophy of the drive
precludes the necessity for special tools. Field repair of the drive
is not practical since there are no user purchasable parts in the
drive.
Product Warranty
----------------
Beginning on the date of shipment to customer and continuing for a
period of five years, Seagate warrants that each product (including
components and sub-assemblies) or spare part that fails to function
properly under normal use due to defect in materials on workmanship
or due to non conformance to the applicable specifications will be
repaired or replaced, at Seagate's option and at no charge to
customer, if returned by customer at customer's expense to Seagate's
designated facility in accordance with Seagate's Warranty Procedure.
Seagate will pay for transporting the repaired or replacement item to
customer. For more detailed warranty information refer to the
Standard terms and conditions of Purchase for Seagate products.
Shock
-----
a. Operating
The drive, as installed for normal operation, shall operate error
free while subjected to intermittent shock not exceeding 10 g's at
a maximum duration of 11 ms (half sinewave). Shock may be applied
in the X, Y, or Z axis.
b. Nonoperating
The limits of nonoperating shock shall apply to all conditions of
handling and transportation. This includes both isolated drives
and integrated drives.
The drive subjected to nonrepetitive shock not exceeding 60 g's at a
maximum duration of 11 ms (half sinewave) shall not exhibit device
damage or performance degradation. Shock may be applied in the X, Y,
or Z axis.
Cooling
-------
Cabinet cooling must be designed by the customer so that the ambient
temperature immediately surrounding the drive will not exceed
temperature conditions. Specific consideration should be given to
make sure adequate air circulation is present around the PCBs to meet
the requirements.
Drive mounting
--------------
When mounting the drive using the bottom holes care must be taken to
ensure that the drive is not physically distorted due to a stiff
non-flat mounting surface. The allowable mounting surface stiffness
is 80 lb/in (14.0 N/mm). The following equation and paragraph define
the allowable mounting surface stiffness:
K*x = 80 lb (14.0 N)
where 'k' represents the mounting surface stiffness (units of lb/in
or N/mm), and, 'k' represents the out-of-plane mounting surface
distortion (units of inches or millimetres). The out-of-plane
distortion ('x') is deter-mined by defining a plane with three of the
four mounting points fixed and evaluating the out-of-plane
deflection of the fourth mounting point when a known force is
applied to the fourth point.
General cable characteristics
-----------------------------
In general, cables having the characteristic impedance's given above
are not available; however, impedance's that are somewhat lower are
satisfactory. A characteristic impedance of 100 ohm 10% is
recommended for unshielded flat or twisted pair ribbon cable.
However, most available cables have a somewhat lower characteristic
impedance. To minimize discontinuities and signal reflections, cables
of different impedance's should not be used in the same bus.
Implementations may require tradeoffs in shielding effectiveness,
cable length, the number of loads, transfer rates, and cost to
achieve satisfactory system operation. If shielded and unshielded
cables are mixed within the same SCSI bus, the effect of impedance
mismatch must be carefully considered. Proper impedance matching is
especially important in order to maintain adequate margin at FAST
SCSI transfer rates.
Cable for "W/WD" model drives
-----------------------------
Only nonshielded cable is applicable. A 68 conductor flat cable or
two, 34 conductor cables shall be used. Conductors should be on 50
(1.27 mm) mil centers to be used with connector. A minimum conductor
size of 28 AWG should be used to minimize noise effects.
Suggested nonshielded flat cable part numbers are:
Flat cable - 35M-3365-68
Twisted pair - Spectra Twist in flat 455-248-68
Equivalent parts may be used.
Cables for "WC" drive models
----------------------------
The 80 pin connector option is intended for use on drives that plug
directly into a wall or bracket mounted connector in the host
equipment. Cable mounted connectors would not be used in such a case.
Installations with cable mounted connectors are not recommended.
Mating connectors for model ST12400W/WD
---------------------------------------
The nonshielded cable connector shall be a 68 conductor connector
consisting of two rows of 34 male contacts with adjacent contacts
1.27 mm (0.050 inch) apart.
Recommended Mating Connector Part Numbers for above flat cable are:
Closed end Amp Model 749925-5 (50 mil conductor centers for
(for cable ends) 28 or 30 AWG wire) This
connector can only be used on
cable ends.
Open end Amp limite 88-5870-294-5 W/O Strain Relief, (25 mil
conductor centers, 30 AWG
wire). Use either on cable
ends or in cable middle
section for daisychain
installations.
The disc drive device connector is a nonshielded 68 conductor
connector consisting of two rows of 34 female pins with adjacent pins
1.27 mm (0.050 inches) apart. The connector is keyed by means of its
shape.
Mating connectors for "WC" models
---------------------------------
The non-shielded connector shall be an 80 conductor connector
consisting of two rows of 40 contacts with adjacent contacts 50 mils
(1.27 mm) apart. The connector is keyed by its shape.
J2 Jumper plug part number
--------------------------
Option select header connector J2 on the PCB uses an unusual type of
jumper, its part number is given here for reference:
Molex 52747-0211 (Seagate P/N 77670952).
Recommended PCB or bulkhead mounted connectors are:
Straight-in (most commonly used): Right angle to PCB connector:
Seagate P/N: 77678703 Seagate P/N: 77678559
Amp US P/N: 2-557103-1 Amp US P/N: 2-557101-1
Amp Japan P/N: 5-175475-9 Amp Japan P/N: 5-175474-9
Grounding
---------
Signal ground (PCBA) and HDA ground are connected together in the
ST12400Wx drive and cannot be separated by the user. The equipment
in which the drive i smounted is connected directly to the HDA and
PCB with no electrically isolating shock mounts. If itis desired for
the system chassis to not be connected to the HDA/PCBA ground, the
systems integrator or user must provide a nonconductive (electrically
isolating) method of mounting the drive in the host equipment.
DC cable and connector
----------------------
The model ST12400W/WD drive receives DC power through a 4 pin
connector mounted at the rear of the main PCB. Recommended part
numbers of the mating connector are listed below, but equivalent
parts may be used.
Mating connector parts
----------------------
Type of cable Connector Contacts (20-14 AWG)
14 AWG AMP 1-480424-0 AMP 60619-4 (Loose Piece)
AMP 61117-4 (Strip)
The model ST12400WC requires no extra DC power cable since both DC
power and SCSI I/O signals are all in the single 80 pin connector.
Physical characteristics
------------------------
This section defines the connectors, cables, signals, terminators and
bus timing needed to implement SCSI.
Physical description
--------------------
The model W and WD drives may be daisychained together or with other
compatible SCSI devices using a common cable. Both ends of the cable
must be terminated. Model ST12400 wide drives do not have on-board
terminator circuits. The ST12400WD drive implements differential
drivers and receivers. The model ST12400W/WC drive implements single
ended drivers and receivers. All signals are common between all SCSI
devices. The drive may be daisychained only with SCSI devices having
the same type drivers and receivers. Devices having single ended
interface circuits cannot be on the same daisychain with devices
having differential interface circuit. A maximum of 16 SCSI devices
(including the Host) may be daisychained together. The SCSI Devices
at both ends of the daisychain are to be terminated. Intermediate
SCSI devices shall not be terminated. Remove or disable (whichever is
applicable) the terminators. Do not remove the terminator power
source selector jumper TP.
"NC" model drives plug into PCB or bulkhead connectors in the Host.
They may be connected in a daisy-chain by the host backplane wiring
or PCB circuit runs that have adequate DC current carrying capacity
to support the number of drives plugged into the PCB or bulkhead
connectors. A single 80 pin I/O connector cannot support the DC
current needs of several drives, so no daisy-chain cables should be
used. A single drive connected via a cable to a host 80 pin I/O
connector is not recommended.
Single ended I/O circuits ("W" models)
--------------------------------------
The maximum total cable length for use with "W" model drives (single
ended I/O driver and receiver circuits) shall be 6 metres (19.7 ft.)
when operating at line data transfer rates of 5 MBytes/sec or less,
and 3 metres (9.85 ft.) when operating at transfer rates greater than
5 Mbytes/sec (FAST SCSI). A stub length of no more than 0.1 metre
(0.33 ft.) is allowed off the mainline interconnection with any
connected equipment. An ideal impedance match with cable terminators
implies a cable characteristic impedance of 132 ohms.
Differential I/O circuits ("WD" models)
---------------------------------------
The maximum total cable length for use with drives having
differential I/O drivers and receiver circuits shall be 25 metres (82
ft.). A stub length of no more than 0.2 metre (0.66 ft.) is allowed
off the mainline interconnec-tion with any connected equipment. An
ideal impedance match with cable terminators implies a cable
characteristic impedance of 122 ohms.
**********************************************************************
F E A T U R E S
**********************************************************************
SEAGATE ST12400W/WC/WD PRODUCT MANUAL 77767457 REV. C 17/3/1995
Scope
-----
This specification describes the Seagate Technology, Inc. Hawk 2
family Model ST12400 Wide SCSI bus Disc Drive. This high capacity,
high performance member of the Seagate 3.5 inch rigid disc family
has a new HDA (Head/Disc Assembly) design having improvements over
previous 3.5-inch Seagate models. It has an embedded SCSI controller.
The Model Hawk 2 Family (Wide bus) drive interface is defined for
functional compatibility to a subset of the Seagate SCSI-2/SCSI-3
Interface Specification 77738479, and the ANSI SCSI-2/SCSI-3
standards. The Model Hawk 2 Family (Wide bus) drives are classified
as "Intelligent" peripherals. The Hawk 2 Family (Wide bus) provides
Level 2 conformance (highest level) with the ANSI SCSI-1 standard.
General description
-------------------
The drives are a 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 drive records and recovers data on 3.7 inch (95 mm) fixed discs.
The drive supports the Small Computer System Interface (SCSI-1,
SCSI-2 and SCSI-3) as described in the ANSI SCSI Interface
Specifications to the extent described in this product specification
(Volume 1). This manual defines the product performance
characteristics of the ST12400 wide family of drives, together with
the SCSI-2/SCSI-3 Interface Product Manual P/N 77738479 (Vol. 2,
Version 2) which describes the general interface characteristics of
this and other families of Seagate 3.5-inch drives.
The drive interface supports multiple initiators, disconnect/
reconnect, self configuring host software and automatic features
that relieve the host from the necessity of knowing the physical
characteristics of the targets (logical block addressing is used).
The Head/Disc Assembly (HDA) is environmentally sealed at the
factory. Air recirculates within the HDA through a nonreplaceable
filter to maintain a contamination free head/disc environment.
NEVER disassemble the Head/Disc Assembly (HDA). This exploded view is
for information only. Do not attempt to service items in the sealed
environmental enclosure (heads, media, actuator, etc.) as this
requires special facilities. The drive contains no parts replaceable
by the user. The drive warranty is voided if the HDA is opened.
The ST12400 wide family drives use a dedicated landing zone at the
innermost radius of the media to eliminate the possibility of
destroying or degrading data by landing in the data zone. The drive
automatically goes to the landing zone when the power is removed.
The ST12400 wide family drives incorporate an automatic shipping lock
which prevents potential damage to the heads and discs that result
from movement during shipping and handling. The shipping lock
disengages when power is applied to the drive and the head load
process begins.
The ST12400 wide family drives decode Track 0 location from the
dedicated servo surface to eliminate mechanical transducer
adjustments and related reliability concerns.
The ST12400 wide family drives use a high performance actuator
assembly that consists of a low inertia, balanced, patented, straight
arm design that provides excellent performance with minimum power
dissipation.
Optional accessories (user installed)
-------------------------------------
The following accessories are available. All kits may be installed in
the field.
- Front Panel Kit (with green LED)
- Single Unit shipping pack kit
- Installation Guide P/N 77767465
- Adapter Accessory Frame Kit P/N 75790701 (adapts 3.5-inch
ST12400W/WD drive to fit in 5.25-inch drive mounting space, does
not work for model ST12400WC).
Prefetch/multi-segmented cache control
--------------------------------------
The drive provides prefetch (read look-ahead) and multi-segmented
cache control algorithms that in many cases can enhance system
performance. "Cache" as used herein refers to the drive buffer
storage space when it is used in "cache" operations. To select
prefetch and cache features the host sends the Mode Select command
with the proper values in the applicable bytes in Mode Page 08h*.
Prefetch and cache operation are independent features from the
standpoint that each is enabled and disabled independently via the
Mode Select command.
Cache operation
---------------
In general, 240 kBytes of the 256 kBytes of physical buffer space in
the drive can be used as storage space for cache operations (984 KB
of 1 MB for drives having 1 MB optional buffer). The buffer can be
divided into logical segments (Mode Select Page 08h, byte 13) from
which data is read and to which data is written. The drive maintains
a table of logical block disk medium addresses of the data stored in
each segment of the buffer. If cache operation is enabled (RCD bit =
0 in Mode Page 08h, byte 2, bit 0. See SCSI Interface Product
Manual), data requested by the host with a Read command is retrieved
from the buffer (if it is there), before any disc access is
initiated. If cache operation is not enabled, the buffer (still
segmented with required number of segments) is still used, but only
as circular buffer segments during disc medium read operations
(disregarding Prefetch operation for the moment). That is, the drive
does not check in the buffer segments for the requested read data,
but goes directly to the medium to retrieve it. The retrieved data
merely passes through some buffer segment on the way to the host. All
data transfers to the host are in accordance with "buffer-full" ratio
rules. See explanations associated with Mode page 02h (disconnect/
reconnect control) in the SCSI Interface Product Manual.
Caching write data
------------------
Write caching is a write operation by the drive that makes use of a
drive buffer storage area where the data to be written to the medium
is stored in one or more segments while the drive performs the write
command.
Write caching is enabled along with read caching. For write caching,
the same buffer space and segmentation is used as set up for read
functions. The buffer segmentation scheme is set up or changed
independently, having nothing to do with whether or not read and
write caching is enabled or disabled. When a write command is issued,
the cache is first checked to see if any logical blocks that are to
be written are already stored in the cache from a previous read or
write command. If there are, the respective cache segments are
cleared. The new data is cached for subsequent Read commands.
If the number of write data logical blocks exceeds the size of the
segment being written into when the end of the segment is reached,
the data is written into the beginning of the same cache segment,
overwriting the data that was written there at the beginning of the
operation. However, the drive does not overwrite data that has not
yet been written to the medium.
Synchronized spindle operation
------------------------------
The synchronized spindles operation allows several drives operating
from the same host to operate their spindles at the same synchronized
rotational rate. Drives operating in a system in synchronized mode
can increase the system capacity and transfer rate in a cost
effective manner.
For "W" and "WD" models the interface consists of a twisted pair
cable that connects the drives in the synchronized system in a
daisy-chain configuration. For "WC" models the reference index signal
("SYNC") signal is on pin J1-37 of the 80-pin I/O connector.
Master/Slave operation is autoarbitrated by each drive after head
load. Alternatively, each drive in the system can be configured by
the host (using the Mode Select command Rigid Disc Drive Geometry
page) to operate in either the master or slave mode.
After loading heads, a drive autoarbitrates for occurences of the
Reference Index Signal (REFIND+). If the drive detects no REFIND+
signal on the line, it assumes master status and begins generating
the REFIND+ signal. This signal will not be visible on the line until
the last drive has powered up, since any unpowered drive holds the
line low.
Using Mode Select command, drives can be re-configured by the host to
be master or slave any time after the last drive has powered up. The
master provides the reference signal to which all other drives phase
lock, including the master. The master can be a drive or the host
computer. All the drives may be configured as slaves, allowing the
host to provide the REFIND+ signal. All drives default to the
synchronized mode when powered up, unless J6 pins 5 and 6 are
jumpered.
Each drive can be configured (jumpered) for the non-synchronized mode
in which it ignores any reference signal that might be present. The
connection of the synchronized reference signal to the host is
required only if the host is to provide the reference signal. If the
host does not provide the reference signal, the host should not be
connected.
Media description
-----------------
The media used on the drive has a diameter of approximately 95 mm
(approximately 3.7 inches). The aluminum substrate is coated with a
thin film magnetic material and overcoated with a proprietary
protective layer for improved durability and environmental
protection.
Defect and error management
---------------------------
The drive, as delivered, complies with this specification. The read
error rate and specified storage capacity are not dependent upon use
of defect management routines by the host (initiator).
Defect and error management in the SCSI system involves the drive
internal defect/error management and SCSI systems error
considerations (errors in communications between Initiator and the
drive). Tools for use in designing a defect/error management plan are
briefly outlined in this section, with references to other sections
where further details are given.
Drive internal defects/errors
-----------------------------
Identified defects are recorded on the drive defects list tracks
(referred to as the primary or ETF defect list). These known defects
are reallocated during the initial drive format operation at the
factory. Data correction by ECC can be applied to recover data from
additional flaws if they occur.
SCSI systems error considerations
--------------------------------*
Information on the reporting of operational errors or faults across
the interface is given in SCSI Interface Product Manual. Message
Protocol System is described in the SCSI Interface Product Manual.
Several of the messages are used in the SCSI systems error management
system. The Request Sense command returns information to the host
about numerous kinds of errors or faults. The Receive Diagnostic
Results reports the results of diagnostic operations performed by the
drive.
Status returned by the drive to the Initiator is described in the
SCSI Interface Manual. Status reporting plays a role in the SCSI
systems error management and its use in that respect is described in
sections where the various commands are discussed.
Electrical description
----------------------
The ST12400W/WC models use single ended interface signals. These
signals must be terminated with 110 ohm active termination circuits
at each end of the total cable. ST12400WC drives have no provisions
for terminators on the PCB. On model ST12400WC some method of
external termination must be provided by the user, systems integrator
or the host equipment manufacturer. On ST12400W drives terminator
power can be supplied from the drive to the I/O connector by the
drive by properly positioning the TP jumper plug and the J2 option
select header. Single Ended circuits use open collector or three
state drivers.
The model ST12400WD uses differential interface signals and each of
these must be terminated at each end of the total cable with 330 ohms
to +5 V and 330 ohms to ground with 150 ohms between each
differential pair. All I/O circuits are open collector, three state
drivers. ST12400WD drives have no provisions for adding terminators
on the PCB. Some method of external termination must be provided
(where needed) by the user, systems integrator or host equipment
manufacturer. The ST12400WD model drive can furnish terminator power
to the SCSI I/O cable by properly positioning jumper plug TP.
Single ended drivers/receivers
------------------------------
Transmitter characteristics
Single ended drives use an ANSI SCSI compatible open collector single
ended driver. This driver is capable of sinking a current of 48 mA
with a low level output voltage of 0.4 volt.
Receiver characteristics
Single ended drives use an ANSI SCSI single ended receiver with
hysteresis gate or equivalent as a line receiver.
Differential drivers/receivers
------------------------------
The drive has no provisions for terminator circuits on the drives.
Differential signals
All differential interface signals consist of two lines denoted
+SIGNAL and -SIGNAL. A signal is true when +SIGNAL is more positive
than -SIGNAL, and a signal is false when -SIGNAL is more positive
than +SIGNAL. All assigned signals shall be terminated at each end
of the cable. Drive user, systems integrator or OEM manufacturer must
provide some external means of termination. Terminator power can be
supplied by the drive to the I/O cable by properly positioning a
jumper plug.
Output characteristics
Each signal driven by differential interface drives shall have the
following output characteristics when measured at the disc drive
SCSI connector:
Low-level output voltage* = 2.0 V maximum at
Low-level output current = 55 milliamps.
High-level output voltage* = 3.0 V minimum at
High-level output current = -55 milliamps
Differential voltage = 1.0V minimum with common-mode voltage ranges
from -7 V dc to +12 V dc.
These voltages shall be measured between the output terminal and the
SCSI device's logic ground reference.
The output characteristics shall additionally conform to EIA
RS-485-1983.
Input characteristics
Each signal received by differential interface drives shall have the
following input characteristics when measured at the disc drive SCSI
connector:
Input current on either input = +2.0 milliamps maximum (includes both
receivers and passive drivers).
This requirement shall be met with the input voltage varying between
-7 V dc and +12 V dc, with power on or off, and with the hysteresis
equaling 35 mv, minimum.
The input characteristics shall additionally conform to EIA
RS-485-1983.
Terminator requirements
-----------------------
Drive I/O termination is not provided internally on ST12400WD or
ST12400WC drives. Terminator circuits, must be provided in some
manner external to the ST12400WD/WC drives by the user, systems
integrator or OEM manufacturer. It is highly recommended that ANSI
SCSI-2 Standard's Alternative 2 termination (active termination) be
used for single-ended ST12400W and ST12400WC applications, especially
if the bus will be operated at transfer rates above 5 Mbytes/sec. The
ST12400W provides on-board active termination that can be disabled by
removal of the enable jumper TE. Power for the external terminators
may be taken from the drive by installing a jumper plug on one of the
J2-TP. If the TP jumper is not installed terminator power must be
supplied by some other source. All single initiator/single target
(nondaisychain) applications require that the Initiator and disc
drive be terminated. Daisychain applications require that only the
units at each end of the daisychain be terminated. All other
peripherals on the chain should not be terminated.
Note. Where terminators are not required, remove external terminator
modules or disable terminators on the model ST12400W by
removing the TE jumper from header J2. Removal of terminator
power source selection jumper TP does not disconnect the
terminators from the circuit.
Note. ACTIVE TERMINATORS ARE HIGHLY RECOMMENDED FOR USE IN THE
DAISYCHAIN AS DESCRIBED ABOVE. ACTIVE AND PASSIVE TERMINATORS
SHOULD NOT BE MIXED ON THE SAME SCSI BUS.
Terminator power
----------------
The model ST12400W/WD drives may be configured to provide terminator
power via pins 17, 18, 51 and 52 of the SCSI Bus, to supply power to
the SCSI bus. The drive can provide power both to external
terminators at the drive end and to the SCSI Bus terminator power
lines to provide power for terminators at the other end of the I/O
cable.
SCSI devices providing terminator power (TERMPWR) shall have the
following characteristics:
V TERM = 4.50V to 5.25V
800 mA min source drive capability
1.0 A maximum
The model ST12400WC drive cannot furnish terminator power, because no
pins in the 80 pin I/O connector are devoted to terminator power.
Options
-------
All options are incorporated or packaged at the manufacturing
facility.
Front panel
-----------
The normal front panel available is black plastic. Other panel colors
may be special ordered. Each panel has a single rectangular green LED
indicator lens which, when glowing, indicates the drive is selected.
**********************************************************************
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.