Comtech EF Data KST-2000A/B - Manual (Page 157)

Ku-Band Satellite Transceiver Revision 9
FSK Remote Control Commands MN/KST2000AB.IOM
E–5
They have these meanings:
The ‘=’ code (target to controller) is
used in two ways: 1. If the controller has sent a query code
to a target (for example UFQ?, meaning
‘what’s the Uplink frequency?’), the
target would respond with
UFQ=xxxxx.x, where xxxxx.x
represents the frequency in question.
2. If the controller sends an instruction to
set a parameter to a particular value,
then, providing the value sent in the
argument is valid, the target will
acknowledge the message by replying
with UFQ= (with no message
arguments).
The ? code (target to controller) is only
used as follows: If the controller sends an instruction to set a
parameter to a particular value, then, if the
value sent in the argument is not valid, the
target will acknowledge the message by
replying (for example) with UFQ? (with no
message arguments). This indicates that
there was an error in the message sent by
the controller.
The * code (target to controller) is only
used as follows: If the controller sends an instruction to set
a parameter to a particular value, then, if
the value sent in the argument is valid,
BUT the modem will not permit that
particular parameter to be changed at that
time, the target will acknowledge the
message by replying (for example) with
UFQ* (with no message arguments).
The ! code (target to controller) is only
used as follows: If the controller sends an instruction code
which the target does not recognize, the
target will acknowledge the message by
echoing the invalid instruction, followed
by the ! character with. Example: XYZ!