DEC 4000 600 series, Руководство пользователя, Страница: 160 / 242

Connecting Additional Devices to Your System
Terminating
and Extending
a Bus To extend a bus, you attach a bus expansion cable (either DSSI
or SCSI, to match the bus) to the bus expansion port and attach
the other end of the cable into the external device.
To terminate a bus, you attach a terminator (either DSSI or
SCSI, to match the bus) to the bus expansion port.
Figure 6–5 shows a system with terminated and extended DSSI
and SCSI buses.
• Bus A, in the example, is a SCSI bus.
Terminate a SCSI bus by attaching a SCSI terminator
!
into the bus expansion port.
Extend a SCSI bus by attaching a SCSI expansion cable
"
into the bus expansion port.
• Bus C, in the example, is a DSSI bus.
Terminate a DSSI bus by attaching a DSSI terminator
#
into the bus expansion port.
Extend a DSSI bus by attaching a DSSI expansion cable
$
into the bus expansion port.
Terminating an
Extended Bus Always terminate a bus. If you extend a bus, move the
terminator (either DSSI or SCSI to match the bus) from the
bus expansion port on the system to the bus expansion port or
connector on the expansion enclosure or standalone device.
For information about attaching a terminator to an R400X
expander, refer to the R400X Expander Installation (EK–R400X–
CM).
6–20 System Configuration