Specifications

4 Message Reference
74
Description
This message is sent to the board to perform dynamic changes to the operation of the
LIU. It allows the user to control the generation of AIS (Blue alarm) and RAI (Yellow
alarm) and to activate various diagnostic loopback modes. It also allows the
configuration of PRBS test sequences.
The confirmation message (if requested) indicates success with a status value of 0.
Parameters
The LIU_MSG_CONTROL message includes the following parameters:
ais_gen
The mode used to generate the Alarm Indication Signal (Blue alarm). The following
table shows the permitted values and their meanings.
Value
Description
0
Do not change AIS/Blue alarm generation mode
1
Disabled; do not generate AIS/Blue alarm
2
Enabled; generate AIS/Blue alarm
rai_gen
The mode used to generate the Remote Alarm Indication (Yellow alarm). The following
table shows the permitted values and their meanings.
Value
Description
0
Do not change RAI/Yellow alarm generation mode
1
Disabled; do not generate RAI/Yellow alarm
2
Forced active; generate RAI/Yellow alarm
3
Automatic generation of RAI/Yellow alarm upon loss of synchronization
4
Automatic generation of RAI/Yellow alarm upon loss of synchronization or BER greater than
1 in 1000 (BER3)
loop_mode
The diagnostic loopback mode. The following table shows the permitted values and
their meanings.