HP 8920B Programmer's Manual page 555

Chapter 8, Programming The Call Processing Subsystem
Programming The CALL BIT Screen
Set Message
This field is used to select the desired forward control channel or forward voice
channel message to be displayed.
The :MESSage command is used to control this field.
The query form of the command (that is, :MESSage?) can be used to determine
which forward control channel or forward voice channel message is currently
being displayed.
for information
See "Reading the CALL BIT Screen Message Fields" on page 556
on how to read the contents of the individual messages.
Syntax
:MESSage <'><Forward Control or Voice Channel Message Word><'>
:MESSage?
Example
OUTPUT 714;"CALLP:AMPS:MESS 'SPC WORD1'"
OUTPUT 714;"CALLP:AMPS:MESS?"
ENTER 714;Message$
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