Seagate ST336732LW/LC プリント

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Cheetah X15 36LP Installation Guide
ST336752LW/LC, ST318452LW/LC, ST336732LW/LC, 
and ST318432LW/LC SCSI interface disc drives
Publication Number: 100139875, Rev. C, June 2002
Handling precautions/Electrostatic discharge protection
• Disc drives are fragile. Do not drop or jar the drive and handle the drive
only by the edges or frame.
• Drive electronics are sensitive to static electricity. Keep the drive in its
antistatic container until you are ready to install it. Wear a wrist strap and
cable connected to ground. Discharge static from all items near or that
will contact the drive. Never use an ohmmeter on any circuit boards.
• Turn off the power to the host system during installation.
• Use caution when troubleshooting a unit that has voltages present.
• Do not disassemble the drive; doing so voids the warranty. Return the
entire drive for depot service if any part is defective.
• Do not apply pressure or attach labels to circuit board or drive top.
Electromagnetic compliance
See Safety and Regulatory Agency Specifications, part number 75789512.
Drive characteristics
ST336752 and ST336732
Formatted capacity .......................................... 36.7 Gbytes 
Max. data blocks  ............................................. 71,687,369 (445DCC9h)
Cylinders and heads (user accessible) ............ 18,497/ 8 heads
Disc rotation ..................................................... 15K RPM
Operating voltages ........................................... +5V
+12V
   Typical operating current (in LVD mode) ....... 0.89A
0.98A
ST318452 and ST318432
Formatted capacity .......................................... 18.4 Gbytes 
Max. data blocks  ............................................. 34,843,670 (222EE56h)
Cylinders and heads (user accessible) ............ 18,497/ 4 heads
Disc rotation ..................................................... 15K RPM
Operating voltages ........................................... +5V
+12V
   Typical operating current (in LVD mode) ....... 0.88A
0.79A
What you need
• A SCSI host adapter
• Phillips screwdriver and four 6-32 UNC drive mounting screws
• An unused drive power connector (not applicable to LC models)
• A SCSI host adapter (sometimes called a SCSI interface card)
To operate at LVD transfer rates, use an LVD-capable SCSI host adapter,
LVD I/O cable and active negation external terminator.
Multimode interface
This drive can operate in single-ended (SE) or low voltage differential (LVD)
mode. This multimode capability provides backwards compatibility so you
can use it with or without an LVD-capable host adapter. The benefits of LVD
technology include faster transfer rates, reduced power consumption,
increased allowable cable lengths, and improved device connectivity.
You can configure the drive to switch between SE and LVD modes automat-
ically or force it to operate in SE mode only. To configure this option, see
Figure 2.
Note. To operate at the Ultra2 rates (or Ultra320 rates on the ST318432
and  ST336732 models) in LVD mode, all devices on the same bus
(cable) must be running in LVD mode. If you add any SE device to
the bus, all devices on that bus operate in SE mode.
Note. Some LVD host adapters provide an LVD connector 
and
 an SE con-
nector on the same host adapter to allow you to run SE and LVD
drives concurrently at their maximum capabilities. Check your SCSI
host adapter documentation. See Figure 3.
Caution. Do not mix LVD drives on the same bus with high voltage differen-
tial (HVD) devices—drive damage may occur.
Installation instructions
1.
Set the SCSI ID
Determine which SCSI IDs are already being used in the system and then
assign this disc drive a SCSI ID that isn’t already being used. Use the J6
connector located on the front of the drive to set the SCSI ID (see Figure 1). 
• If you have an LC model drive, the host normally sets the ID over the I/O
interface, so you don’t need to worry about this step.
• Most Cheetah
®  
X15 36LP drives are factory set with the SCSI ID set at
0. If this is the only SCSI drive in your system and there are no other
SCSI devices on the daisychain, you can leave this drive’s SCSI ID set to
0 and proceed to the next step.
• The host system’s SCSI controller usually uses SCSI ID 7.
• Some systems provide a cable designed to connect to the J5 jumper
block on the drive to remotely set the ID. You can connect this cable to J5
and use the host-provided remote switch to set the SCSI ID.   
Figure 1.
Setting the SCSI ID
2.
Configure termination
If you are installing the drive in a system that has other SCSI devices
installed, terminate only the end devices on the SCSI bus (cable). This drive
does not have internal terminators or any other way of adding internal termi-
nation on the drive. You must provide external termination when termination
is required. This is normally done by adding an inline terminator on the end
of the cable. See Figure 3 for an illustration showing a system configuration
that uses an external terminator.
• Use active (ANSI SCSI-2 Alternative 2) single-ended terminators when
terminating a bus operating in single-ended mode.
• Use SPI-2-compliant active low voltage differential terminators when ter-
minating a SCSI Ultra2 bus operating in LVD mode.
• The host adapter is normally on the end of the bus and internally termi-
nated. You can configure your bus with another device on the end if you
remove termination from the host adapter.
3.
Configure terminator power
Terminators have to get power from some source. The default configuration
results in the drive not supplying termination power to the bus. You should
normally leave this drive set at this default unless your host system requires
the drive to supply termination power to the bus. To configure this drive to
supply termination power to the bus, place a jumper on J2 pins 1 and 2 as
shown in Figure 2. 
• Host systems designed to use LC drives normally provide termination
power from the host adapter or other source. For this reason, LC model
drives cannot be configured to provide termination power to the bus.
SCSI ID = 0
(default)
Jumper Plug
(enlarged to
show detail)
J6
Drive
Front
Pin 1
Reserved
A
2
A
1
A
0
A
L
E
D
R
E
S
3
SCSI ID = 1
SCSI ID = 2
SCSI ID = 3
SCSI ID = 4
SCSI ID = 5
SCSI ID = 6
SCSI ID = 7
SCSI ID = 8
SCSI ID = 9
SCSI ID = 10
SCSI ID = 11
SCSI ID = 12
SCSI ID = 13
SCSI ID = 14
SCSI ID = 15
J1
DC Power
J1
68 Pin
SCSI I/O
Connector
Drive HDA
Rear
SCSI ID = 8
SCSI ID = 9
SCSI ID = 10
SCSI ID = 11
SCSI ID = 12
SCSI ID = 13
SCSI ID = 14
SCSI ID = 15
A
not used
3 A2 A1
SCSI ID = 0
SCSI ID = 1
SCSI ID = 2
SCSI ID = 3
SCSI ID = 4
SCSI ID = 5
SCSI ID = 6
SCSI ID = 7
A0
J5
Pin 1
4P
3P 2P
1P
Pin 1
+5V
Ground
(default)