Seagate ST150176LW/LC Computer Drive User Manual


 
Barracuda 50 Installation Guide, Rev. A 19
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.
Figure 4 shows the three most common termination configu-
rations. ST150176LW drives do not have internal termina-
tors or any other way of adding internal termination on the
drive. You must provide external termination to these drives
when termination is required. This is normally done by add-
ing an in-line terminator on the cable. See Figure 9 on page
27 for an illustration showing a system configuration that
uses an inline terminator.
Use active (ANSI SCSI-2 Alternative 2) single-
ended terminators when terminating a bus oper-
ating in single-ended mode.
Use SPI-2-compliant active low voltage differential termina-
tors when terminating a SCSI Ultra2 bus operating in LVD
mode.
Some controllers prefer to remain terminated even if they
are in the middle of the chain. Also, some controllers treat
the internal and external chains as separate logical buses.
This means you may need to terminate both the first and
last devices on both logical buses to achieve proper termi-
nation. If necessary, refer to your system or controller doc-
umentation to see how this is handled in your particular
system.