Hard Drive: SEAGATE: ST3285N 248MB 3.5"/SL SCSI2 FAST
S T 3 2 8 5 N SEAGATE
Native| Translation
------+-----+-----+-----
Form 3.5"/SLIMLINE Cylinders 1689| | |
Capacity form/unform 248/ MB Heads 3| | |
Seek time / track 12.0/ 4.0 ms Sector/track | | |
Controller SCSI2 SI/FAST Precompensation
Cache/Buffer 128 KB SEACACHE Landing Zone
Data transfer rate 2.000 MB/S int Bytes/Sector 512
10.000 MB/S ext SYNC
Recording method ZBR RLL1/7 operating | non-operating
-------------+--------------
Supply voltage 5/12 V Temperature *C |
Power: sleep W Humidity % |
standby 1.0 W Altitude km |
idle 3.0 W Shock g |
seek 5.7 W Rotation RPM
read/write W Acoustic dBA
spin-up W ECC Bit
MTBF h 250000
Warranty Month
Lift/Lock/Park YES Certificates
Layout
SEAGATE ST3285N INSTALLATION GUIDE
Rear +- 50 pin SCSI Interface I/O connector
View |
| DC power
(TOP) +------------- -----------+ +-5-G-G-12+
-------------+||||||||||||||||||||||||1+-+ O O O O +----
(BOTTOM) +-------------------------+ +---------+
xxxxxx1 xxxxxx1 xxxxxx1
Terminating Resistor Packs
ST-3285N +-----+
Left View |o o o1
(TOP) |o o o| +-+
Front --------------------++-+-++----+X|I/O connector
| | | +-+
SCSI Address ID 1 -+ | |
ID 2 ---+ |
ID 4 -----+
ST-3285N
Right View
+-----+ +-------+
| o o4| | o o o6| (TOP)
+-+ |1o o | |1o o o |
DC PowerX+-+-----+--+-------+-------------------------------
+-+
Jumpers
SEAGATE ST3285N JUMPER SETTING
Jumper Setting
==============
Rear +- 50 pin SCSI Interface I/O connector
View |
| DC power
(TOP) +------------- -----------+ +-5-G-G-12+
-------------+||||||||||||||||||||||||1+-+ O O O O +----
(BOTTOM) +-------------------------+ +---------+
xxxxxx1 xxxxxx1 xxxxxx1
Terminating Resistor Packs
ST-3285N +-----+
Left View |o o o1
(TOP) |o o o| +-+
Front --------------------++-+-++----+X|I/O connector
| | | +-+
SCSI Address ID 1 -+ | |
ID 2 ---+ |
ID 4 -----+
ST-3285N
Right View
+-----+ +-------+
| o o4| | o o o6| (TOP)
+-+ |1o o | |1o o o |
DC PowerX+-+--+--+--+--+----+-------------------------------
+-+ | |
| +--+----+
| Active/Passive Termination
+-+-+ +--+----+
Terminator Power +---+----------------------------+
+-+-+ | Active: Pins 1 & 2 shorted |
| | only (+2.85V to |
| | 110 ) for FAST |
| | SCSI; |
| |Passive: Pins 2 & 4 shorted |
| | AND pins 5 & 6 shorted |
| | (+5V and GND to |
| | 220/330 ) for |
| | standard SCSI. |
| +--------------------------------+
|
+-------------+---------------------------------------------------+
|Terminator Power: From SCSI Connector ---------------- Pins 1 & 2|
| -----------------------------------------------+
| From Power Connector --------------- Pins 1 & 3|
| -----------------------------------------------+
| To SCSI Connector Only ------------- Pins 3 & 4|
| -----------------------------------------------+
| From Power Connector and ----------- Pins 1 & 2|
| AND to SCSI Bus ------------------------- 3 & 4|
| -----------------------------------------------+
| Terminating Resistors not Installed -Pins 2 & 4|
+-----------------------------------------------------------------+
ST-3285N
Front View
+------------------ SCSI ID's (none for ID0)
| not used if ID set on side jumpers
| +-------------- Ext. Spindle Clock Synch
| | pin-5 is Clock Ground
| | +------------ Remote LED
TOP) +-+-+ | | +---+---+-- Reserved
+-4-2-1-+-+-+---+---++
| o o o o o-o o o o o|+-------+
|1o o o o o+o o o o o||o o o o|+
--+--------------------+1o o o o+---------------
++-+-+-++
(BOTTOM) | | | +-- Remote LED
| | +---- Ext. Spindle Clock Sync
| | pin-5 is Clock Ground
| +------ Remote Start Enable
+-------- Parity Enable
Terminator power source jumper block ------------------------------------ To select the termination power source, install jumpers as follows: - To provide terminator power to the SCSI connector and the drive terminator packs, install jumpers on pins 1 and 2 and pins 3 and 4 of the terminator power source jumper block. This is the default.
- To select the drive power connector as the termination power source for the resistor packs, install a jumper on pins 1 and 3 of the terminator power source jumper block.
- To select the SCSI connector as the termination power source for the resistor packs, install a jumper on pins 1 and 2 of the terminator power source jumper block.
- To provide terminator power to the SCSI connector from the drive power connector only, install a jumper on pins 3 and 4 of the terminator power source jumper block.
Active/passive termination jumper block
---------------------------------------
To select active termination (the default), install a jumper on pins
1 and 2 of the active/passive termination jumper block. To select
passive termination, install jumpers on pins 5 and 6 and pins 2 and
4 of the active/pas-sive termination jumper block, and change the
terminating resistor packs.
Caution. When installing jumpers on the options jumper block and the
user-configuration jumper block, be careful to install jumpers on the
correct pins. Install jumpers only on pins 1 through 4 of the options
jumper block and pins 1 through 6 of the user-configuration jumper
block. If you install jumpers on pin pairs that are meant to accept
only twisted pair connectors, the drive may not function properly.
Remote LED connection
---------------------
Remote LED pins are located on two separate jumper blocks: the
options jumper block and the user-configuration jumper block. Attach
a two-pin remote LED connector to either jumper block, as follows:
- User-configuration jumper block, pins 9 and 10. Use any 2-pin, 2-mm connector and an LED from LiteOn , part number LTL-3231A.
- Options jumper block, pins 7 and 8. Use any 2-pin, 0.1-inch connector and an LED from LiteOn , part number LTL-3231A.
External spindle synchronization option
---------------------------------------
You can synchronize the spindle motors of an array of drives by
connecting a twisted pair to each drive. The maximum cable length is
6 feet (1.8 meters).
Spindle synchronization pins are located on two separate jumper
blocks: the options jumper block and the user-configuration jumper
block. Use either jumper block to synchronize an array of drives, as
follows:
- User-configuration jumper block. Use one strand of the twisted pair to connect together pin 7 of the user-configuration jumper block of each drive. Use the other strand to connect together pin 8 of the user-configuration jumper block of each drive.
- Options jumper block. Use one strand of the twisted pair to connect together pin 5 of the options jumper block of each drive. Use the other strand to connect together pin 6 of the options jumper block of each drive.
The spindle-synchronization characteristics can be controlled by the
Mode Select command using the RPL bits in byte 17 of the Rigid Disc
Geometry page.
In the default mode, all drives arbitrate during startup to see which
drive will be the synchronized master. When the drives are
calibrating their heads, they each check for a reference signal
pulse. The drive that becomes ready first checks for the reference
signal, and when it does not detect a pulse, it takes over as the
master and begins sending reference pulses. All other drives
synchronize their spindles to the reference signal as they in turn
become ready.
Install
SEAGATE ST3655 FAMILY PRODUCT MANUAL
Notes On Installation
=====================
Installation direction
----------------------
horizontally vertically
+-----------------+ +--+ +--+
| | | +-----+ +-----+ |
| | | | | | | |
+-+-----------------+-+ | | | | | |
+---------------------+ | | | | | |
| | | | | |
| | | | | |
+---------------------+ | +-----+ +-----+ |
+-+-----------------+-+ +--+ +--+
| |
| |
+-----------------+
The drive will operate in all axis (6 directions).
Drive mounting
--------------
You can mount the drive in any orientation. Follow the guidelines
below appropriate to the set of mounting holes you elect to use:
either bottom mounting holes or side mounting holes.
Caution. Do not remove factory-installed labels from the drive or
cover them with additional labels. If you do, you may void
your warranty. Factory-installed labels contain information
required when servicing the product.
Bottom mounting holes
---------------------
Use 6-32 UNC screws in three of the four available bottom mounting
holes.
Caution. Do not insert the bottom mounting screws more than 0.20
inches (6 turns) into the drive frame. If you use a screw
that is too long, you could damage the drive.
Side mounting holes
-------------------
Use 6-32 UNC screws in three of the six available side mounting
holes. Do not use all three mounting holes on the same side of the
drive.
Caution. Do not insert side mounting screws more than 0.13 inches (4
turns) into the drive frame. If you use a screw that is too
long, you could damage the drive.
Shock and vibration
-------------------
All shock and vibration specifications assume that the drive is
mounted in a recommended mounting configuration. Inputs are measured
at the drive mounting screws. Shock measurements are based on an 11
msec, half sine wave shock pulse, not to be repeated more than twice
per second.
During operating shock and vibration, there is no physical damage to
the drive or performance degradation. During nonoperating shock and
vibration, the read/write heads are positioned in the shipping zone.
DC power
--------
Except during the write procedure, you can apply power to the drive
or remove power from the drive in any sequence without losing data or
damaging the drive. If you remove the power from the drive during the
write procedure, you may lose the data currently being written.
Power management
----------------
The drive supports power-management modes that reduce its overall
power consumption. The drive automatically changes from one mode to
another based in response to interface activity. You do not need to
change any parameters or send any special commands to make the drive
change modes. The power-management modes are described below.
- Spinup. The spindle is coming up to operating speed. The power
consumed in this mode is equivalent to the average power
during the first 10 seconds after the drive begins to spin
up.
- Seeking. The servo electronics are active and the read/write heads
are moving to a specific location on the disc. The
read/write electronics are powered-down. The power
consumed in this mode is equivalent to the average power
measured while executing random seeks with a 2-revolution
(26.6 msec) dwell between seeks. The drive enters this
mode from the Idle mode.
- Read/write. The drive is reading or writing. All electronics are
active and the read/write heads are on track. The drive
enters this mode from the Idle mode.
- Idle. The drive spindle motor is up to speed and the servo
electronics are active. The heads are on track, ready to
accept and execute any command without delay. The read/write
electronics are powered down. The drive can enter this mode
from any other mode (except the Standby mode).
- Standby. This mode is not implemented.
Hardware and interface
----------------------
The SCSI-2 interface consists of a 9-bit bidirectional bus (8 data
bits and 1 parity bit) plus 9 control signals supporting multiple
initiators, disconnect and reconnect, and self-configuring host
software. Logical block addressing is used.
The physical interface consists of single-ended drivers and receivers
using asynchronous or synchronous communication protocols that
support cable lengths of up to 6 meters (3 meters for Fast SCSI) and
a bus interface transfer rate up to 5 Mbytes per second asynchronous
and 10.0 Mbytes per second synchronous. The bus protocol supports
multiple initiators, disconnect and reconnect, additional messages,
and 6-byte and 10-byte command descriptor blocks.
SCSI-2 compatibility
--------------------
The drive interface is described in the Seagate Wren SCSI-2 Interface
Product Manual, publication number 77765466. The drive complies with
the mandatory subset of the ANSI SCSI-2 interface. The Fast SCSI-2
interface is based on the ANSI Small Computer System Interface-2
(SCSI-2): document number ANSI X3.131-199 x (X3T9.2/86-109 Rev. 10h).
Handling and static-discharge precautions
-----------------------------------------
After you unpack the drive, and before you install it in a system, be
careful not to damage it through mishandling. Observe the following
standard handling and static-discharge precautions:
Caution: - Keep the drive in its static-shielded bag until you are ready to complete the installation. Do not attach any cables to the drive while it is in its static-shielded bag.
- Before handling the drive, put on a grounded wrist strap, or ground yourself frequently by touching the metal chassis of a computer that is plugged into a grounded outlet. Wear a grounded wrist strap throughout the entire installation procedure.
- Handle the drive by its edges or frame only.
- The drive is extremely fragile_handle it with care. Do not press down on the drive top cover.
- Always rest the drive on a padded, antistatic surface until you mount it in the host system.
- Do not touch the connector pins or the printed circuit board. Do not touch the printed circuit cable between the circuit board and the head/disc assembly.
- Avoid wool or synthetic clothing, carpeting, plastics and Styrofoam; these items cause static discharge.
- Do not remove the factory-installed labels from the drive or cover them with additional labels. If you do, you may void the warranty. Some factory-installed labels contain information needed to service the drive. Others are used to seal out dirt and contamination.
Hot-plugging
------------
If there is more than one SCSI device daisy-chained on the bus, you
can connect and disconnect the drive I/O and power connector if the
following conditions are met:
- The drive you are disconnecting (or connecting) is not the device supplying terminator power or terminating resistance to the bus.
- During hot-plugging, do not add or remove terminator power or resistors from the bus.
- During hot-plugging, do not use the bus for I/O transactions. If you are installing a drive on the bus, there must be no I/O transactions until the drive is connected and ready. If you are removing a drive from the bus, there must be no I/O transactions until the drive is completely disconnected.
To avoid damage to the disc and head, the spindle must be completely
stopped and the heads must be parked before you remove the drive from
the system. There are two ways to stop the spindle and park the
heads:
- If the drive is not configured to use the remote start/stop feature, disconnect the DC power cable from the drive DC power connector and wait 30 seconds.
- If the drive is configured to use the remote start/stop feature, issue the SCSI stop command and wait 30 seconds.
SCSI connector
--------------
You can daisy-chain the drive with a maximum of seven other SCSI
devices (including the host) that have single-ended drivers and
receivers using a common cable. SCSI ID 7, by convention, is usually
used for the host adapter. No drive can have the same SCSI ID as the
host adapter.
All signals are common between all SCSI devices. The SCSI devices at
both ends of the daisy-chain must be terminated; the intermediate
SCSI devices should not be terminated.
The 50-conductor, nonshielded mating cable connector consists of two
rows of 25 female contacts with adjacent contacts 0.100 inches apart.
The drive connector is a nonshielded, 50-pin connector consisting of
two rows of 25 pins with adjacent pins 0.100 inches apart. The
connector is keyed with a slot.
Cable requirements
------------------
The characteristic impedance of the cable should be between 90 ohms
and 140 ohms. However, most available cables have a somewhat lower
characteristic impedance. To minimize discontinuities and signal
reflections, do not use cables of different impedances in the bus.
Your design may require trade-offs in shielding effectiveness, the
length of the interface cable, the number of loads, and the transfer
rates. If your design uses both shielded and nonshielded cables
within the same SCSI bus, you must allow for the effects of impedance
mismatch.
To minimize noise effects, use a minimum conductor size of 28 AWG.
Use only nonshielded cable connectors. Use a 50-conductor flat cable
or 25-conductor twisted-pair cable. The recommended nonshielded flat
cable part numbers are shown in the following table:
Part Manufacturer
Flat Cable 3M-3365-50 Twisted Pair
Spectra Twist-N-Flat 455-248-50
Single-ended cable
------------------
The single-ended SCSI cable must meet the following requirements:
- The cable cannot be longer than 6.0 meters.
- A cable stub cannot be longer than 0.1 meter, from the mainline interconnection to any device. Stubs must be separated by at least 0.3 meter.
Fast synchronous data transfer
------------------------------
When using fast synchronous data transfer rates, the SCSI interface
cable must meet the following additional requirements:
- The cable cannot be longer than 3.0 meters.
- A characteristic impedance of 90 ohms to 132 ohms is recommended for nonshielded flat cable or twisted-pair ribbon cable.
- The signal attenuation at 5 MHz must not be greater than 0.095 dB per meter.
- The DC resistance at 20*C must not exceed 0.230 ohms per meter.
- The propagation delay delta of a shielded, twisted-pair cable must not exceed 20 nsec per meter.
DC power connector
------------------
The drive is equipped with a 4-pin power connector.
Terminators
-----------
The interface is terminated with three SIP resistor modules that plug
into sockets on the printed circuit board. You can order the drive in
the active (default) or passive configuration, or without
terminators, depending on your application. When installing or
removing terminators, follow these guidelines:
- If you are installing only one drive, and your system contains only one initiator (for example, a stand-alone host computer) leave the terminators installed on the drive.
- If you are installing multiple drives in a daisy-chain configuration, remove the terminators from all drives except the drives (or initiators) connected to the ends of the cable.
- If your application requires no terminators, remove the terminators from the drive circuit board. Removing the terminator power source selection jumper does not disconnect the terminator resistors from the circuit.
- If you use Fast SCSI transfer rates, you must use the active termination options. If the transfer rate is 5.0 Mbytes per second or less, you can use either method of termination.
Active termination ------------------ All interface signals are single-ended and must be terminated at the drive with a 110-ohm resistor to +2.85V. This is the default. The Seagate part number for the 110-ohm terminator is 502155-001.
Passive termination ------------------- All interface signals with the drive are single-ended and must be terminated with 220 ohms to +5V and 330 ohms to ground at each end of the cable. All signals use open-collector drivers or three-state drivers. The Seagate part number for the 220/330-ohm terminator is 75916526-9.
Single-ended drivers and receivers
----------------------------------
The drive uses single-ended drivers and receivers.
- Transmitter characteristics. The drive uses 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 volts.
- Receiver characteristics. The drive uses an ANSI SCSI single-ended receiver with hysteresis gate or equivalent as a line receiver. The loss in the cable is defined as the difference between the voltages of the input and output signals.
Features
SEAGATE ST3655 FAMILY PRODUCT MANUAL
Reliability
-----------
Read error rates are measured with automatic retries and data
correction with ECC enabled and all flaws reallocated. MTBF is
measured at nominal power at sea level and 40*C ambient temperature.
Nonrecoverable read errors 1 per 10 13 bits transferred
Seek errors 1 per 10 7 physical seeks
MTBF 250,000 power-on hours
Service life 5 years
Acoustics
---------
Sound pressure is measured at idle from 1 meter above the drive top
cover.
Sound pressure, typ 34 dBA
Sound pressure, max 38 dBA
Seek time
---------
All seek time measurements are under nominal conditions of
temperature and voltage with the drive mounted horizontally. In the
table below:
- Track-to-track seek time is the average of all possible
single-track seeks in both directions.
- Average seek time is a true statistical random average of at least
5,000 measurements of seeks in both directions between
random cylinders, less overhead.
- Full-stroke seek time is one-half the time needed to seek from
logical block address zero (LBA 0) to the maximum LBA
and back to LBA 0.
Note. Host overhead varies between systems and cannot be specified.
Drive internal overhead is measured by issuing a no-motion
seek. Drive overhead is typically less than 1.0 msec.
Read look-ahead and caching
---------------------------
The drive uses algorithms that improve seek performance by storing
data in a buffer and processing it at a more convenient time. Three
methods are employed: read look-ahead, read caching and write
caching.
Thermal compensation
--------------------
The thermal compensation feature compensates for position offset of
the selected head due to variations in temperature. The drive
automatically performs thermal compensation during startup and every
2 minutes thereafter.
You can preempt the automatic compensation by issuing a Rezero Unit
command (01H). The drive performs the thermal calibration and then
sets a timer and waits 2 minutes before performing the calibration
again.
Thermal compensation increases the execution time of the command
during which it is performed by 100 msec (typ) to 350 msec (max).
FCC verification
----------------
ST3655 family drives are intended to be contained solely within a
personal computer or similar enclosure (not attached to an external
device). As such, a drive is considered to be a subassembly even when
individually marketed to the customer. As a subassembly, no Federal
Communications Commission authorization, verification or
certification of the device is required.
Seagate Technology, Inc. has tested these drives in an enclosure as
described above to ensure that the total assembly (enclosure, disc
drive, motherboard, power supply, etc.) does comply with the limits
for a Class B computing device, pursuant to Subpart J of Part 15 of
the FCC rules. Operation with noncertified assemblies is likely to
result in interference to radio and television reception.
Radio and television interference. This equipment generates and uses
radio frequency energy and, if not installed and used in strict
accordance with the manufacturer's instructions, may cause
interference to radio and television reception.
This equipment is designed to provide reasonable protection against
such interference in a residential installation. However, there is no
guarantee that interference will not occur in a particular
installation. If this equipment does cause interference to radio or
television, which can be determined by turning the equipment on and
off, you are encouraged to try one or more of the following
corrective measures:
- Reorient the receiving antenna.
- Move the device to one side or the other of the radio or TV.
- Move the device farther away from the radio or TV.
- Plug the equipment into a different outlet so that the receiver and computer are on different branch outlets.
If necessary, you should consult your dealer or an experienced
radio/television technician for additional suggestions. You may find
helpful the following booklet prepared by the Federal Communications
Commission: How to Identify and Resolve Radio-Television Interference
Problems. This booklet is available from the Superintendent of
Documents, US Government Printing Office, Washington, DC 20402. Refer
to publication number 004-000-00345-4.
Note. This digital apparatus does not exceed the Class B limits for
radio noise emissions from computer equipment as set out in the radio
interference regulations of the Canadian Department of
communications.
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