Cisco VGD-1T3, Руководство по настройке программного обеспечения

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Basic Configuration Using the Command-Line Interface on the Cisco VGD 1T3 Voice Gateway
Configuring Clocking
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Cisco VGD 1T3 Voice Gateway Software Configuration Guide
flash:dsp_c5510_flex.8_2_800.r 8.2.800 c5510
flash:dsp_c5510_flex_11_0_800. 11.0.800 c5510
DSP# Type Version Filename
2/13 C5510 23.6.0 system:/bundled_fw_image
2/14 C5510 23.6.0 system:/bundled_fw_image
2/15 C5510 23.6.0 system:/bundled_fw_image
2/16 C5510 23.6.0 system:/bundled_fw_image
Configuring Clocking
The time-division multiplexing (TDM) bus on the Cisco VGD 1T3 voice gateway backplane can receive
an input clock from one of these basic sources on the gateway:
• CT3 feature card
•
An external T1 clock source feed directly through the Building Integrated Timing Supply (BITS)
interface port on the motherboard
• Free-running clock providing clock from an oscillator
Note BITS is a single building master timing supply. BITS generally supplies DS1 and DS0 level timing
throughout an office. In North America, BITS is the clock that provides and distributes timing to a
wireline network’s lower levels.
Trunk Feature Card Ports
The TDM bus is synchronized with the CT3 trunk card. The CT3 feature card uses an M13 multiplexer
to receive the DS1 clock. Each port on each trunk feature card slot has a default clock priority. Also,
clock priority is configurable through the tdm clock priority CLI command.
External Clock
The TDM bus can be synchronized with an external clock source that can be used as an additional
network reference. If no clocks are configured, the system uses a primary clock through a
software-controlled default algorithm. If you want the external T1 clock (using the BITs interface) as
the primary clock source, you must configure it using the tdm clock priority CLI command; the external
clock is never selected by default.
The BITS interface requires a T1 line composite clock reference set at 1.544 MHz.
Free-Running Clock
If there is no good clocking source from a trunk feature card or an external clock source, then choose the
free-running clock from the local oscillator through the tdm clock priority CLI command.
The following task helps you configure the clock source and clock source priority used by the TDM bus: