ACCULINK 3163 DSU/CSU3-20 March 1999 3163-A2-GB20-10Selecting the Timing SourceThe DSU/CSU provides the ability to select a masterclock (timing) source that is used to synchronize all of theT1 and data port interfaces on the DSU/CSU. The clockfor each interface is at the appropriate rate for thatinterface (e.g., 1.544 Mbps for the T1 interfaces, theconfigured port rate for the data ports), and it isindependent of the master clock rate. This means that themaster clock rate and the DSU/CSU interface rates maybe different.The clock source configuration options enable you toselect either the network interface, the synchronous dataport, or the internal clock. A sample procedure forconfiguring timing is given in the following section,Configuring for Network Timing. For more information onconfiguration options, refer to Appendix C, ConfigurationOptions.Configuring for Network Timing ProcedureTo configure for network timing:1. From the top-level menu screen, select Cnfig.2. Select the configuration option set to be copiedinto the Edit area by using the appropriateFunction key. Use the scroll keys, if necessary.3. Select Edit.4. From the Edit screen, press the key until theGen selection appears on the screen.5. Select Gen.F1Edit:NET Chan GenF2 F36. Press F1 (Next) to display the next configurationoption (Clock Src).7. Select the master clock source. For network, pressF2 (note that network is also the default).F1Clock Src:NETNext NET Prt1F2 F3
