Silicon Graphics 330 User Manual page 136

5: SCSISelect Configuration Utility
Send Start Unit Command
120
When set to yes, the SCSI device may disconnect from the SCSI bus. The SCSI device,
however, may choose not to disconnect, even if permitted by the SCSI controller (this can
usually be configured on the SCSI device). When set to no, the SCSI device is not allowed
to disconnect from the SCSI bus. The default setting is yes.
You should leave Enable Disconnection set to yes if two or more SCSI devices are
connected to the SCSI controller. This optimizes SCSI bus performance. If only one SCSI
device is connected to the SCSI controller, set Enable Disconnection to no to achieve
slightly better performance.
This option, which is supported by some SCSI devices, determines whether the Start Unit
Command (SCSI command 1B) is sent to the SCSI device (most devices do not require
this). Enabling this option reduces the load on your computer's power supply by
allowing the SCSI controller to power-up SCSI devices one-at-a- time when you boot
your computer. Otherwise, the devices all power-up at the same time. Most devices
require you to set a jumper before they can respond to this command.
When set to yes, the Start Unit Command is sent to the SCSI device during bootup. When
set to no, each SCSI device powers-up in its normal fashion. The default setting is no.
Note: The Send Start Unit Command setting is valid only if the host adapter BIOS is
enabled.
If this option is enabled for more than one SCSI device, the Start Unit Command is sent
first to the device with the lowest SCSI ID. When this device responds to the SCSI
controller, the Start Unit Command is sent to the next highest SCSI ID with a setting of
yes. The process continues until all supported devices respond to the SCSI controller.
Note: If many drives are set to yes for Send Start Unit Command, the boot time
varies depending on how long it takes each drive to spin up.
007-4278-001