Command Reference Guide

3Com Router 5000 Family and Router 6000 Family t1 sendloopcode ● 323
Command Reference
t1 sendloopcode
Purpose Use the t1 sendloopcode command to set the loopback mode of the specified
far-end T1 line.
Use the undo t1 sendloopcode command to remove the corresponding setting.
Syntax t1 line-number sendloopcode { inband-line-up | fdl-ansi-line-up |
fdl-ansi-payload-up }
undo t1 line-number sendloopcode { inband-line-up | fdl-ansi-line-up |
fdl-ansi-payload-up }
Parameters line-number
T1 line number. Valid values are 1 to 28.
inband-line-up
Places the far-end T1 line in a line loopback by sending
in-band signals.
fdl-ansi-line-up
Places the far-end T1 line in a line loopback by using
ANSI-compliant FDL.
fdl-ansi-payload-up
Places the far-end T1 line in a payload loopback by
using ANSI-compliant FDL.
Example Send the in-band signal on T1 line 1 on CT3 interface 1/0/0 to place the far-end T1
line in line loopback mode.
<3Com > system-view
[3Com ] interface t3 1/0/0
[3Com -T3 1/0/0] t1 1 sendloopcode inband-line-up
Send line loopback control code on T1 line 1 on CT3 interface 1/0/0 to disable line
loopback on the far-end T1 line.
<3Com > system-view
[3Com ] interface t3 1/0/0
[3Com -T3 1/0/0] undo t1 1 sendloopcode fdl-ansi-line-up
View This command can be used in the following views:
■ CT3 Interface view
Description Loopback is an effective way of diagnosis. You may place a far-end device into
loopback mode either at command line on it or by sending loopback control code to
it. The types and formats of loopback control code supported on T1 interfaces are
compliant with ANSI T1.403.
Loopback is divided into line loopback and payload loopback by loopback method.
They differ in the sense that the data stream is looped back at the framer with line
loopback but not with payload loopback.