Command Reference Guide

48 ● clock (Serial Interface) 3Com Router 5000 Family and Router 6000 Family
Command Reference
clock (Serial Interface)
Purpose Use the clock command to set clock selection mode for a synchronous serial
interface.
Syntax
clock { dteclk1 | dteclk2 | dteclk3 | dteclk4 }
Parameters dteclk1
Sets the interface clock selection mode to DTE clock
option 1.
dteclk2
Sets the interface clock selection mode to DTE clock
option 2.
dteclk3
Sets the interface clock selection mode to DTE clock
option 3.
dteclk4
Sets the interface clock selection mode to DTE clock
option 4.
Example Set the synchronous serial interface working as DTE to use the clock selection option
dteclk2.
[3Com -Serial0/0/0] clock dteclk2
View This command can be used in the following views:
■ Serial intervace view
Description If the synchronous serial interface operates as DCE, its clock defaults to DCE clock; if
the interface operates as DCE, its clock defaults to dteclk1.
Different operating clocks are selected for the synchronous serial interfaces working
as DTE and DCE, as shown in the following figure:
Figure 1 Selecting a clock for a synchronous serial interface
In the figure, "TxClk" represents transmitting clock and "RxClk" receiving clock.
As a DCE device is required to provide clock for the remote DTE device, you must
select DCEclk as the operating clock for the synchronous serial interface working as
DCE.
DCE DTE
TxClk
RxClk