Connecting Additional Devices To Your System; Bus Expansion Ports; Extending A Fast Scsi Bus; Connecting Additional Devices: Rules - DEC 4000 600 series Owner's Manual

Connecting Additional Devices to Your System

Connecting Additional Devices to Your System
Bus Expansion A bus expansion port on the front of most mass storage
Ports compartments enables you to extend the bus that runs through
that compartment outside the system. As a result, you can
connect external mass storage devices, either standalone devices
or devices in an expander, such as the R400X, to the buses inside
your system. Note, however, that you can only connect DSSI
devices to a DSSI bus and only SCSI devices to a SCSI bus.
Figure 6–4 shows the location of the bus expansion ports on the
DEC 4000 AXP system.
Extending a Buses that run fast SCSI cannot be extended outside the system.
Fast SCSI Bus If you wish to extend a SCSI bus that is currently running fast
SCSI, you must reconfigure the hardware in that compartment.
Contact your Digital service representative.
Connecting Each DEC 4000 AXP mass storage compartment can hold up
to four devices. However, each bus can support up to seven
Additional
mass storage devices. This means that you can connect three,
Devices: Rules
and possibly more, external drives to a bus that supports a
compartment.
For instance:
•
•
6–18 System Configuration
If a compartment holds four drives, you can connect three
external drives to the bus that supports that compartment.
If a compartment holds one drive, you can connect six
external drives to the bus that supports that compartment.