Hard Drive: SEAGATE: ST3550A MEDALIST 452MB 3.5"/SL ATA2 FAST
S T 3 5 5 0 A M E D A L I S T SEAGATE
NO MORE PRODUCED Native| Translation
------+-----+-----+-----
Form 3.5"/SLIMLINE Cylinders | 1018| |
Capacity form/unform 452/ 550 MB Heads 5| 14| |
Seek time / track 12.0/ 3.5 ms Sector/track | 62| |
Controller IDE / ATA2 FAST/ENHA Precompensation
Cache/Buffer 256 KB LOOK-AHEAD Landing Zone
Data transfer rate 3.500 MB/S int Bytes/Sector 512
11.100 MB/S ext
Recording method RLL 1/7 operating | non-operating
-------------+--------------
Supply voltage 5/12 V Temperature *C 5 55 | -40 70
Power: sleep W Humidity % 8 80 | 5 95
standby 0.9 W Altitude km -0.305 3.048| -0.305 12.192
idle 3.2 W Shock g 2 | 75
seek 5.6 W Rotation RPM 4500
read/write 5.4 W Acoustic dBA 34
spin-up 7.0 W ECC Bit
MTBF h 250000
Warranty Month 24
Lift/Lock/Park YES Certificates CSA,FCC,UL478,VDE
Layout
SEAGATE ST3550A DRIVE PRODUCT MANUAL 3612-001, REV.A
+-------------------------------------------------------++-1
| || |J5
| |+-+
| |XX J7
| |
| |XX
| I/O |XX
| Connector |XX J1
| |XX
| |XX
+---+ |XX
J8 +-+| |XX
| || |XX1
1-+| |
+---+ +--+ |XX Power
| |++| |XX J3
+----------------------------------------------++++-----+
J6
Jumpers
SEAGATE ST3550A DRIVE PRODUCT MANUAL 36192-001, REV.A
Jumper setting
--------------
x = Jumpers are set by factory
J5 Master/slave and slave present jumper block
-----------------------------------------------
--+----+-- PCB
3|o x|1
4|o o|2
+----+
1- 2 OPEN One drive only
x 3- 4 OPEN
1- 2 CLOSE Drive is slave
3- 4 OPEN
1- 2 OPEN Drive is master with slave present
3- 4 CLOSE
If only one drive is installed, do not install any jumper on the
master/slave present jumper block.
If there are two drives installed on the bus, one must be configured
as a master and the other as a slave. No more than two drives can be
connected on the AT bus.
To configure the drive as a master with slave present, install a
jumper on pins 3 and 4 only of the master/slave and slave present
jumper block.
If both the master and the slave are ST3550A drives, you do not need
to install a jumper on pins 3 and 4. This is because the master can
detect the presense of the slave using the interface DASP-signal. If
the drives in your application do not implement the DASP-signal,
install the jumper on the master drive only.
To configure the drive as a slave, install a jumper on pins 1 and 2
only of the master/slave and slave present jumper block.
J6 Factory test
----------------
The pins on this jumper block are used for testing during the manu-
facturing process; they are not for field use.
J7 Mini power connector
------------------------
--+---------+-- PCB
| o o o |
+---------+
| | |
| | +---- + 5 VDC
| +------- +12 VDC
+---------- Ground
J8 Options jumper block
------------------------
13 11 9 7 5 3 1
+-------------------+
|o o o o o x|
|o o o o o o o|
+-------------------+
12 11 10 8 6 4 2
pin- 3 Removed for key pin- 8 Spindle clock I/O pin 28 pin- 9 Clock ground pin-10 External spindle clock sync. pin-13 Remote LED - pin-14 Remote LED +
Note: All other pins are reserved. Do not use them.
J8 Remote LED connection
--------------------------
If you want to add a remote LED, attach a two-pin, 0.1-inch connector
to pins 13 and 14 of the options jumper block.
J8 Spindle synchronization
---------------------------
The spindle clock signal (SPSYNC-) synchronizes the ratation of up to
12 drives in a system. When two or more drives are connected to the
host, the drives automatically configure themselves in either of two
ways:
- The spindle synchronization clock signal is generated by the host. The drives configure themselves as slaves and synchronize their spindles according to the host signal.
- The spindle synchronization clock signal is generated by one of the drives. The master configures itself as the originator of the SPSYNC-signal; the other drives become slaves, or receivers of the SPSYNC-signal.
The slave receives the signalto synchronize its spindle with the host
or master and synchronizes its index with the SPSYNC-signal. Synchro-
nization is achieved, and is indicated by the drive setting DRDY.
(If a drive that was already synchronized loses synchronization, but
continues to function, it does not clear DRDY.)
There are three ways to enable spindle synchronization:
- Enable pin 28 (SPSYNC-) of the AT interface connector by installing a jumper on pins 8 and 10 of the options jumper block.
- Connect a twisted pair to pins 9 and 10 of the options jumper block to transmit and receive SPSYNC-. Use one strand of the twisted pair to connect pin 9 of the options jumper block of each drive. Use the other strand to connect pin 10 of the options jumper block of each drive. The cable should not be longer than six feet (1.8 meters).
The spindle clock uses a single-ended TTL, active low, 75Hz signal
with a clock period of 13.34 msec 0.5% and a duty cycle of 0.5 sec
minimum, 500 sec maximum. The spindle clock leading edge to index
leading edge is 0 250 sev.
J3 DC Power and pin connector assignments
-------------------------------------------
--+------------+-- PCB pin 1 +12 VDC
| 1 2 3 4 | pin 2 +12 Volts Return
+------------+ pin 3 + 5 Volts Return
pin 4 + 5 VDC
Install
SEAGATE ST3550A DRIVE PRODUCT MANUAL 36192-001, REV.A
Notes on installation
=====================
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.
Notes: Regardless of which set of holes you use, use only three
mounting screws.
For optimum performance, format the drvie in the same orien-
tation as you mount it in the host system.
Bottom mounting holes
Use three 6-32 UNC screws in the 4 available bottom mounting holes.
Do not insert the bottom mounting screws more than 0.20 inch (5.08mm
6 turns) into the drive frame. If you use a screw that is too long,
you could damage the drive.
Side mounting holes
Use three 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.
Use one or both of the following: the side mounting hole near the
power connector or the side mounting hole (on the other side of the
drive) near the interface connector.
Use at least one, but no more than two, of the other four side
mounting holes.
Do not insert side mounting screws more than 0.13 inch (3.3 mm,
4 turns) into the drive frame. If you use a screw that is too long,
you could damage the drive.
I/O cable and connector
-----------------------
The I/O connector is a 40-pin connector. The even pins are next to
the edge of the printed circuit board; the odd pins are away from the
printed circuit board. Pin 1 is near the 4-pin power connector.
There is no pin 20 because that location is used as a key. The corre-
sponding pin hole on the cable connector should be plugged to prevent
the connector from being installed upside down. The I/O cable cannot
be any longer than 18 inches (0.46 meters).
2-Drive configuration
---------------------
The drive can be daisy-chained with a second drive if the second
drive meets the same interface specifications. In this configuration,
one drive is designated as the master and the other as the slave.
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.
DC power
--------
Except during the write procedure, you can turn off and turn on power
to the drive in any sequence without loss of data or damage to the
drive. If you turn off the power during the write procedure, you may
lose the data currently being written.
All voltage tolerance of 5% must be maintained under all conditions,
including ripple.
Power management
----------------
The drive implements intelligent power management by automatically
changing power modes based on interface activity. Power management
reduces the average power consumption considerably compared to a
drive without this feature.
Interface commands and interface-selectable parameters allow you to
customize the power management configuration. Transitions between the
Standby mode and the Idle mode (through the Spinup mode) are con-
trolled by both the power management configuration and the interface
demands. Transitions between the Idle mode, the Read/Write mode and
the Seeking mode are controlled solely by interface requests.
NOTE: If you install the ST3550A as a slave with a master drive that
does not support power management (for example ST1239A drive),
do not use power management commands on the ST3550A.
SPINUP The drive brings the spindle and discs up to operating
speed. Power in this mode is defined as the average power
during the first 10 seconds after starting spinup. This
mode is entered from the Standby mode.
SEEKING The drive moves the actuator to position the read/write
heads to a specific location on the disk surface in anti-
cipation of a read/write operation. Read/write electronics
are powered down and servo electronics are active. Power
used during this mode is the average power measured while
executing random seeks with a 2-revolution dwell between
Seek commands.
READ/WRITE The drive performs a read or write operation from or to
the disk medium. Read/write electronics are active and the
servo is in the track-following mode. This mode is entered
from the Idle mode.
IDLE The drive spindle is up to speed and the heads are track-
following. Some of the drive electronics are powered down.
Commands that require media access return the drive to the
Active mode with a 3-msec delay required to repower the
drive's electronics. The drive responds to any command
that does not require media access without leaving the
IDLE mode. The status reported to the host is that the
drive is ready.
STANDBY The drive spindle is stopped, the heads are parked in the
landing zone, the actuator is latched, and some of the
drive electronics are powered down. The drive reports to
the host that it is in the Ready mode. The drive remains
in the Standby mode to respond to commands that do not re-
quire media access. The drive returns to the Active mode
to respond to commands that require media access after a
delay required to spin up the drive.
FCC Verification
----------------
This equipment has been tested with a Class B computing device and
has been found to comply with Part 15 of the FCC rules. These limits
are designed to provide reasonable protection against harmful inter-
ference in residential installations. This equipment generates, uses,
and can radiate radio frequency energy, and if not installed and
used in accordance with the instructions, may cause harmful inter-
ference to radio communications. There is no gurantee that interfer-
ence will not occur in a particular installation.
Caution: Any changes or mofifications to the equipment by the user
not expressly approved by the grantee or or manufacturer could void
the user's authority to operate such equipment.
Note: This digital apparatus does not exceed the Class B limits for
radio noise emission from computer equipment as set out in the radio
interference regulations of the Canadian Department of Communica-
tions.
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:
Use a ground wrist strap.
Handle the drive by its edges. Do not put any pressure on the drive
top cover. Do not touch the PC board.
Always rest the drive on a padded surface until you mount it in the
host system.
Do not remove Seagate factory-installed labels from the drive or
cover them with additional labels. If you do, you void the warranty.
Factory-installed labels contain information needed to service the
drive.
Thermal compensation
--------------------
The thermal compensation feature compensates for thermal-related
position offset on the selected head. Thermal compensation is per-
formed during start-up and ervery 2 minutes thereafter. This peri-
odic compensation coincides with a host command service operation.
Due to thermal compensation, the execution time of the last command
increases by 100msec - 350 msec.
Start/Stop time
---------------
Within 20 seconds after DC power is applied, the drive is ready.
Within 15 seconds after DC power is removed, the drive is stopped.
Read/Write head auto-park
-------------------------
Upon power-down, the read/write heads automatically move to the
shipping zone. The heads park inside the maximum data cylinder. When
power is applied, the heads recalibrate to track 0.
Features
SEAGATE ST3550A DRIVE PRODUCT MANUAL 36192-001, REV.A
Format capacity
---------------
You cannot low-level format the ST3550A drive.
During manufacture, all media flaws are allocated to reserved
sectors; therefore, they do not reduce the formatted capacity.
Guaranteed formatted: 452.415 MB
Guaranteed total sectors: 883,624
Bytes per sector: 512
Recommended logical configuration
---------------------------------
The drive is configured in translation mode. DOS limits the number of
sectors per track to 63. (The drive limits sector per track to 256).
Set the number of heads to satisfy the following relationship:
16 (sectors per track)(heads) 4,096
When you configure the drive in CMOS, the logical sectors cannot
exceed the physical capacity of the drive. The total logical capacity
of the drive is determinated by the following formula:
total sectors = (log. heads)(log. sectors per track)(log.cylinders)
You can verify the number of sectors per track and the number of
heads by using the Identify Drive command. To maximize the capacity
of the drive, the following geometry is recommended:
Cylinders 1018
Read/Write Heads 14
Sectors per Track 62
Multisegment read look-ahead buffer
-----------------------------------
The drive uses the read lock-ahead buffer to improve performance by
eliminating access times under certain conditions. The read look-
ahead buffer contains four 64K-segments of RAM (one for writing and
three for reading) for a total capacity of 256 Kbytes.
This buffer is used to store the next logical sectors after the
previously read sector into a buffer before those sectors are
actually requested by the host. The read look-ahead buffer stores
data from the start of a read until the buffer segment is full, or
until another command is received from the host.
Acoustics
---------
34 dBA typical sound pressure at 1 meter, in Idle mode.
38 sBA maximum sound pressure at 1 meter, in Idle mode.
Access Time Definition and Timing
---------------------------------
Seek time is a true statistical average of at least 5,000 measure-
ments of seek time. All measurements are under nominal conditions of
temperature and voltage with the drive mounted horizontally. In the
table below, the following definitions apply:
Track-to-track seek time is the average of all possible single-track
seeks in both directions.
Average seek time is measured by executing seeks in both directions
between random cylinders.
Full-stroke seek time is half the time needed to seek from track 0 to
the maximum track and back to track 0.
+----------------------------------+--------+
|Track-to-Track msec. typ. | 3.5 |
| msec. max. | 4 |
| Average msec. typ. | 12 |
| Average msec. max. | 14 |
|Full-Stroke msec. typ. | 30 |
| msec. max. | 32 |
|Latency msec. avg. | 6.67 |
+----------------------------------+--------+
NOTE: Host overhead varies between systems and cannot be specified.
Drive internal overhead is measured by issuing a no-motion-
seek. Overhead is typically less than 0.5 msec.
UL/CSA Certification
--------------------
This drive is recognized in accordance with UL 478 and UL 1950.
It's certified to VDE 0805/05.90 and EN 60950/1.88, as tested by VDE.
It's also certified to CSA C22.2 No. 220-M1986, and CSA C22.2 No. 950
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