Comtech EF Data LBC-4000 - Manual (Page 108)

LBC-4000 L-Band Up/Down Converter System with Ethernet Revision 2
Serial-based Remote Product Management MN-LBC4000A
7–6
7.2.2.5 Instruction Code Qualifier
This is a single character that further qualifies the preceding instruction code. Code Qualifiers obey the following rules:
From Controller‐to‐Target, the only permitted characters are:
Character Definition
=
(ASCII code 61) This character is used as the Assignment Operator (AO). It establishes that the Instruction Code that precedes it is to
be used as a command to assign or configure operation. The instruction set that follows serves to assign the Target’s
new parameter setting or operational value.
Example:
From Controller-to-Target, MUT=1 means “enable the mute function.”
?
(ASCII code 63) This character is used as the Query Operator (QO). It establishes that the Instruction Code that precedes it is to be used
as a query that returns the Target’s current configured parameter setting or operational value.
Example: From Controller-to-Target, MUT? means “what’s the current state of the MUTE function?”
From Target‐to‐Controller, the only permitted characters are:
Character Definition
=
(ASCII code 61) This character is used in two ways:
a. If the Controller sends a query to the Target – for example: MUT? meaning “what’s the current state of the MUTE function?”, the
Target would respond with MUT=x, where x represents the state in question: 1 being enabled, and 0 being disabled.
b. If the Controller sends an instruction to set a parameter to a particular value, and the value sent is valid, the Target acknowledges
the message and responds with MUT= (with no message arguments).
?
(ASCII code 63) If the Controller sends an instruction to set a parameter to a particular value, and the value sent is not valid, the Target then
acknowledges the message and responds with, for example, MUT? (with no message arguments). This indicates that there was an
error in the message sent by the Controller.
!
(ASCII code 33) If the Controller sends an instruction code that the Target does not recognize, the Target responds by echoing the invalid instruction,
followed by !
Example: XYZ!