R0106-HP MSR Router Series Interface Command Reference(V7)

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[Sysname] interface serial 2/1/0
[Sysname-Serial2/1/0] fe1 code ami
Related commands
fe1 data-coding
fe1 data-coding
Use fe1 data-coding to enable or disable user data inversion for an E1-F interface.
Use undo fe1 data-coding to restore the default.
Syntax
fe1 data-coding { inverted | normal }
undo fe1 data-coding
Default
Data inversion is disabled.
Views
E1-F interface view
Predefined user roles
network-admin
Parameters
inverted: Enables user data inversion.
normal: Disables user data inversion.
Usage guidelines
To prevent 7e in valid data from being mistaken for padding characters, HDLC inserts a bit 0 after every
five bit 1 in the data stream. In data inversion, every bit is changed into its opposite value. (Bit 1 is
changed into bit 0, and bit 0 changed into bit 1.) After the inversion, at least one bit 1 is present in every
eight consecutive bits.
When AMI encoding is used on an E1-F interface, data inversion eliminates the presence of multiple
consecutive zeros.
The data inversion setting must be the same at the two ends of an E1-F line.
Examples
# Enable user data inversion on E1-F interface Serial 2/1/0.
<Sysname> system-view
[Sysname] interface serial 2/1/0
[Sysname-Serial2/1/0] fe1 data-coding inverted
Related commands
fe1 code
fe1 detect-ais
Use fe1 detect-ais to enable AIS test on an interface.
Use undo fe1 detect-ais to disable AIS test.