R2511-HP MSR Router Series Voice Command Reference(V5)

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Parameters
internal: Specifies the internal crystal oscillator clock, which can be the one on the main board or the one
on the E1/T1 card, as the clock source of the E1/T1 interface. Note that the SIC card does not have a
crystal oscillator clock. In this case, the E1/T1 interface is the master in time synchronization.
line: Specifies the clock on the peer device as the clock source of the E1/T1 interface. In this case, the
E1/T1 interface is a client in time synchronization.
line primary: Sets the T1/E1 interface to preferentially use the clock of the peer device as its clock source.
Usage guidelines
When digital voice E1/T1 interfaces perform TDM timeslot interchange, it is important for them to
achieve clock synchronization to prevent frame slips and bit errors.
Depending on your configurations on E1/T1 interfaces, the system adopts different clocking approaches.
When there is a subcard VCPM on the main board, the clock selection principle is as follows:
• If the line keyword is specified for all interfaces, the clock on the interface with the lowest number
is adopted. In case the interface goes down, the clock on the interface with the second lowest
number is adopted.
• If the line primary keywords are specified for one interface, the clock on the interface is adopted.
In one system, you can do this on only one interface.
• If the line keyword is specified for one interface and the internal keyword for all others, the clock on
the interface is adopted.
• Generally, you cannot set the clock source for all interfaces in a system as internal to prevent frame
slips and bit errors. You can do this however if the remote E1/T1 interfaces adopt the line clock
source.
When there is no VCPM on the main board, the configuration of each MIM/FIC is independent but only
one interface can be set as line primary.
Examples
# Set the TDM clock source on interface E1 1/0 to line clock.
<Sysname> system-view
[Sysname] controller e1 1/0
[Sysname-e1 1/0] tdm-clock line
timer dl
NOTE:
This command applies to R2 signaling only.
Use timer dl to configure timeouts of R2 line signals.
Use undo timer dl to restore the defaults.
Syntax
timer dl { answer | clear-back | clear-forward | seizure | re-answer | release-guard } time
undo timer dl { answer | clear-back | clear-forward | seizure | re-answer | release-guard }
Views
R2 CAS view