23
A Jumper Settings
The hard disk drives are shipped without SCSI terminators. These drives are
ready to use on a SCSI cable with a built-in active terminator.
Each hard disk drive is configured at the factory for optimum performance on
most systems. With the possible exception of setting the SCSI address, you
should not change default settings. Changing the disk drive configuration can
cause unexpected or undesirable results.
Jumper Legend
Table A-1 shows the jumper descriptions for all drives. All jumper-controlled
features are not available on all drives. (An * indicates a factory default setting.)
Table A-1. General Jumper Description
ID
Description
Ax
SCSI Addresses (A0, A1, A2 and A3)
See the "Set the SCSI Address" step in the chapter "Prepare
Drive for Installation" for detailed information.
LED
Light Emitting Diode Drive Activity Light
Not a jumper in the traditional sense. This is where the drive
activity light connects to the drive.
DS
Delay Spin-Up
On*
Motor start up is delayed by the sum of the SCSI ID times 6
seconds after power is applied; i.e., Drives 0 and 8 spindles
start immediately, drives 1 and 9 start after a 6 second delay,
drives 2 and 10 start after a 12 second delay, and so forth.
Off
Motor start up begins immediately after system power up,
unless Motor Start Enable is on. If Motor Start Enable is on, it
overrides this setting.
ME
Motor Start Enable
On
Drive spindle starts when the Start Unit command is received
from the host system. If the Delay Spin-Up feature is on, the
Delay Spin-Up feature is overridden.