SDCP Operation
3-34 3166-A2-GB20-10
November 1998
Selecting the Timing Source
The 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. The clock for each interface is at the appropriate rate for that
interface (e.g., 1.544 Mbps for the T1 interface, the configured port rate for the
data ports), and it is independent of the master clock rate. This means that the
master clock rate and the DSU/CSU interface rates may be different.
The clock source configuration options enable you to select either the network
interface, a synchronous data port, or the internal clock.

Configuring for Network Timing

Procedure
To configure for network timing:
1. From the top-level menu screen, select Cnfig.
2. Select the configuration option set to be copied into the Edit area by using the
appropriate Function key. Use the scroll keys, if necessary.
3. Select Edit.
4. From the Edit screen, press the key until the Gen selection appears on
the screen.
5. Select Gen.
F1
Edit:
NET Chan Gen
F2 F3
6. Press F1 (Next) to display the next configuration option (Clock Src).
7. Select the master clock source. For network, press F2 (note that network is
also the default).
F1
Clock Src:NET
Next NET Prt1
F2 F3