Seagate ST31200N, Руководство по эксплуатации продукта

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Product Manual - Hawk 1LP Family SCSI-2 (Volume 1), Rev. A 35
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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 single-ended
I/O only).
Off See above explanations for TP jumpers.
J5
Jumper
Installation
Jumper Function Description
A
0
,A
1
,A
2
* Drive ID on SCSI Bus (J6 may be used instead, as ID circuits on J5 and J6 are in parallel.
Use only one set for ID). The drive ID is binary coded positionwise i.e., jumper in position
A
2
is drive ID 4, in position A
1
is ID 2, position A
0
is ID 1 and
no jumpers is ID 0. Default is ID = 0.
J6
Jumper
Installation
Jumper Function Description
A
2
,A
1
,A
0
* Drive ID on SCSI bus. Either J5 or J6 (optional) may be used to select drive ID. Both 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 J5 and J6 the same. Default is ID = 0.
SSP* Used only as a cable connection for the reference index signal () (J6 Pin 6, bottom)
for sync spindle feature. J6 pin 5 is GRD. See paragraphs 10.2, 5.7 for description of
synchronized spindle operation. A jumper should be installed whenever no cable is
connected. Default is jumper installed.
LED* No jumper ever installed. These pins used to connect a cable for a remote LED indicator. Pin
3 (top, nearest HDA), the anode connection, connects in the drive to the +5V supply through
a pull-up resistor. Pin 4 (bottom), the cathode connection connects in the drive to signal
common through the emitter-collector junction of a transistor switch that controls the LED on/
off condition.
RES Reserved position. No jumper to be installed.
* See note [2] above.
10.2 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. Details of the electrical and physical interfaces follow in paragraphs
10.2.1 and 10.2.1.2 and 10.2.1.3. The system operation is described in paragraph 5.7. Drives to be
synchronized should be the same make and model.
10.2.1 Electrical description
The electrical interface consists of one digital TTL reference index signal and ground. The reference index
signal () 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 Daisy-chain fashion as shown in Figure 5.7-1.