Specifications

50
Channelized and Electrical Interface Line Card Installation and Configuration
78-16417-02
Configuring and Troubleshooting Line Card Interfaces
• Using T3 Controller Loopback Modes, page 51
• Shutting Down the T3 Controller, page 52
• Configuring the T3 Controller to Respond to Remote T3 Loopback Commands, page 53
Selecting a T3 Controller
You must enter the controller T3 slot/port command before any other configuration commands to select
the T3 controller you want to configure. The example that follows is for a 6-port channelized T3 (T1)
line card in slot 6 of a Cisco 12000 Series Router:
Router# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)# controller T3 6/0
Router(config-controller)#
Setting the Framing Type for the T3 Controller
To specify the framing type, use the controller command framing [c-bit | m23 | auto-detect].
You can set c-bit framing format as follows:
Router(config-controller)# framing c-bit
Router(config-controller)#
You can set m23 framing format as follows:
Router(config-controller)# framing m23
Router(config-controller)#
Specifying the Cable Length
For the cablelength value command, user-specified T3 cable lengths are structured into ranges as
follows: 0 to 49 feet and 50 to 450 feet. If you enter a cable length value that falls into one of these
ranges, the range within which that value applies is used.
Note The configuration is based on feet, not meters.
To specify cable length, use the cablelength value controller configuration command
where
• value is a numeral from 0 to 450 feet (137 meters).
• Default value is 49 feet (15 meters).
An example follows that specifies a cable length of 40 feet (12 meters).
Router(config-controller)# cablelength 40
Router(config-controller)#
Note In the preceding example, a cable length of 40 feet (12 meters) is specified, which means that the 0 to
49 (0 to 15 meters) range is used. If you change the cable length to 45 feet (13 meters), then the 0 to 49
(0 to 15 meters) range still applies. Further, if you specify a cable length of 100 feet (30 meters), then
change it to 200 feet (60 meters), the 50 to 450 (15 to 137 meters) range applies in each case; therefore,
these changes have no effect. Only moving from one range 0 to 49 (0 to 15 meters) to the other range 50
to 450 (15 to137 meters) has an effect. The actual cable-length number you enter is stored in the
configuration file.