Seagate ST136475LW/LC User Manual
22
Barracuda 36 Installation Guide, Rev. B
For information about how to terminate your drive, refer to the
appropriate drive-specific section.
appropriate drive-specific section.
Figure 2.
SCSI bus termination
Terminator power
You usually will not need to change this option and can normally
leave the drive configured as it was shipped from the factory. For
information about how to change the terminator power option on
your drive, refer to the appropriate drive-specific section.
leave the drive configured as it was shipped from the factory. For
information about how to change the terminator power option on
your drive, refer to the appropriate drive-specific section.
I/O circuits and data path widths
• “LW” and “LC” models use SCSI multimode I/O circuits. Multi-
mode circuits operate either in single-ended mode or low volt-
age differential mode. No high voltage differential devices
should be connected in the I/O daisy chain with “LW” or “LC”
model drives. The state of the I/O “DIFFSNS” line determines
whether the devices on the SCSI bus operate their I/O circuits
in single-ended or low voltage differential mode. The host
device on the SCSI bus operates the “DIFFSNS” line. How-
ever, the SE jumper on J2 forces “DIFFSNS” to nominal
age differential mode. No high voltage differential devices
should be connected in the I/O daisy chain with “LW” or “LC”
model drives. The state of the I/O “DIFFSNS” line determines
whether the devices on the SCSI bus operate their I/O circuits
in single-ended or low voltage differential mode. The host
device on the SCSI bus operates the “DIFFSNS” line. How-
ever, the SE jumper on J2 forces “DIFFSNS” to nominal
Internal
SCSI device
Internal
SCSI device
Controller
External
SCSI device
External
SCSI device
External
SCSI
cable
cable
Internal SCSI cable
Terminate
Internal
SCSI device
Internal
SCSI device
Controller
Internal SCSI cable
Terminate