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

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[Sysname] interface serial 2/0:0
[Sysname-Serial2/0:0] crc 32
data-coding (CE1/PRI interface)
Use data-coding inverted to enable user data inversion on a CE1/PRI interface.
Use data-coding normal to disable user data inversion on a CE1/PRI interface.
Use undo data-coding to restore the default.
Syntax
data-coding { inverted | normal }
undo data-coding
Default
Data inversion is disabled.
Views
CE1/PRI interface view
Default command level
2: System level
Parameters
inverted: Enables user data inversion.
normal: Disables user data inversion.
Usage guidelines
To prevent 7e in valid data from being taken for stuffing characters, HDLC inserts a zero after every five
ones in the data stream, then inverts every one bit into a zero and every zero bit into a one. This ensures
that at least one out of every eight bits is a one. When AMI encoding is adopted on an E1 interface, the
use of data inversion can eliminate the presence of multiple consecutive zeros.
On the CE1/PRI interfaces at two ends of an E1 line, use the same data inversion setting.
Examples
# Enable user data inversion on CE1/PRI interface E1 2/0.
<Sysname> system-view
[Sysname] controller e1 2/0
[Sysname-E1 2/0] data-coding inverted
detect-ais
Use detect-ais to enable alarm indication signal (AIS ) test on an interface.
Use undo detect-ais to disable AIS test.
Syntax
detect-ais
undo detect-ais