Paradyne ACCULINK 316x - Manual (Page 91)

Operation
3-49 3160-A2-GB22-10 December 1996
Timing
The 316x DSU/CSU provides the ability to select a
master clock (timing) source that is used to synchronize
all of the T1 and data port interfaces on the DSU/CSU.
When a master clock source is selected, the DSU/CSU
will synchronize to the master clock and derive clocking
for all of the interfaces on the DSU/CSU. The clock for
each interface will be at the appropriate rate for that
interface (e.g., 1.544 Mbps for the T1 interfaces, the
configured port rate for the data ports) and independent of
the master clock rate. This means that the master clock
rate and the DSU/CSU interface rates may be different.
The DSU/CSU will automatically fall back to the internal
master clock when a failure of the selected master clock is
detected.
NOTE
For Model 3161 DSU/CSUs, the
external clock provides timing for
up to eight slots in the carrier.
Each Auxiliary Backplane must
have its own external clock input.
The DSU/CSU clock source configuration option
enables you to select one of five sources for the master
clock, either the Network T1 interface, the DSX-1
Drop/Insert T1 interface, Port 1, internal clock, or external
clock. If external clocking is selected, you must use the
clock rate configuration option to specify the clock rate.
Two examples for configuring timing are given below. For
more information on the configuration options, refer to
Appendix C. Figure 3-32 shows some common clocking
configurations.
496-14341a-01
3160/3164
NETWORK
CLOCK: NETWORK
3160/3164
CLOCK: NETWORK
3160/3164
CLOCK: NETWORK CLOCK: INTERNAL
3160/3164
3160/3164
CLOCK: EXTERNAL
3160/3164
CLOCK: NETWORK
PBX
CLOCK: DTE (DSX-1 CONNECTOR)
3160/3164
CLOCK: NETWORK
3160/3164
TERMINAL
EQUIPMENT
CLOCK: PORT 1
3160/3164
CLOCK: NETWORK
3160/3164
Figure 3-32. Common Clocking Configurations