Cisco Broadband Cable Command Reference Guide

Chapter 2 Cisco Cable Modem Termination System Commands
OL-1581-05
cable upstream frequency
Note If both a Cisco uBR-MC16E cable interface line card and a Cisco uBR-MC16C and/or a
Cisco uBR-MC16S cable interface line card are present in the chassis, a spectrum group in the 42 MHz
to 65 MHz range should not be assigned.
To configure the default upstream frequency (which is no fixed frequency), enter the cable upstream n
frequency command without specifying a center frequency.
Examples The following example shows how to configure the upstream center frequency for port 0, located in slot
6, to 5,700,000 Hz:
Related Commands
Table 2-7 Allowable Frequency Range for the cable upstream frequency Command
Frequency Range Supported Cable Interfaces Minimum Cisco IOS Releases
5 to 42 MHz All supported cable interfaces All releases supported for the
Cisco CMTS
5 to 65 MHz Cisco uBR-MC16E,
Cisco uBR7111E and
Cisco uBR7114E routers
Router(config-if)# cable upstream 0 frequency 5700000
Router(config-if)# exit
Router(config)# exit
Router# show running-config | include frequency
cable upstream 0 frequency 5696000
Router#
Note Cisco cable interface line cards always program the upstream’s center frequency in 16 KHz increments,
and this is the frequency displayed by the lines added to the router’s configuration and by the show
controllers cable upstream command. For example, if you use the cable upstream frequency
command to specify a center frequency of 27 MHz (cable upstream x frequency 27000000), the actual
center frequency will be 27.008 MHz, which is the next highest 16 KHz boundary. The configuration file
will therefore show the line cable upstream 0 frequency 27008000.
The following example shows how to allow the Cisco CMTS to dynamically specify a center frequency
for the upstream port 0:
Router(config-if)# no cable upstream 0 frequency
Command Description
cable spectrum-group (global
configuration)
Cisco IOS Release 12.0(13)SC,
12.1(4)EC, and 12.2(4)BC1
Creates spectrum groups, which contain one or more upstream
frequencies.
show controllers cable Displays information about the cable interface, including the
upstream center frequency.
Cisco Broadband Cable Command Reference Guide
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