B.2.4.5 Instruction Code Qualifier - Comtech EF Data LPOD Hardware Installation And Operation Manual

LPOD C- / Ku-Band Outdoor Amplifier/ Block Up Converter (BUC)
Appendix B
B.2.4.5 Instruction Code Qualifier
This single character further qualifies the preceding instruction code. Code Qualifiers obey the
following rules:
1. From Controller-to-Target, the only permitted values are:
=
(ASCII code 61
?
(ASCII code 63)
2. From Target-to-Controller, the only permitted values are:
=
(ASCII code 61)
?
(ASCII code 63)
!
(ASCII code 33)
*
(ASCII code 42)
#
(ASCII code 35)
The = (ASCII code 61) is used as the assignment operator, and is used to
indicate that the parameter defined by the preceding byte should be set to the
value of the argument(s) that follow it. For example: In a message from
Controller-to-Target, MUT=1 would mean 'enable the Mute function'.
The ? (ASCII code 63) is used as the query operator, and is used to indicate that
the Target should return the current value of the parameter defined by the
preceding byte. For example: In a message from Controller-to-Target, SWR?
would mean 'returns the value of the internal software revision installed in the unit'.
The = code is used in two ways:
First, if the Controller has sent a query code to a Target (for example: MUT?,
meaning 'is the Mute enabled or disabled?'), the Target would respond with
MUT=x, where x represents the state in question: 1 being 'enable' and 0 being
'disable'.
Second, if the Controller sends an instruction to set a parameter to a particular
value, and if the value sent in the argument is valid, then the Target will
acknowledge the message by replying with MUT= (with no message arguments).
The ? code 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 MUT? (with no message arguments).
This indicates that there was an error in the message sent by the Controller.
The ! code 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. Example: XYZ!
The * code 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 Target is in the wrong
mode (e.g., standby mode in redundancy configuration) and will not permit that
particular parameter to be changed at that time, the Target will acknowledge the
message by replying, for example, with MUT* (with no message arguments).
The # code (Target-to-Controller) is only used as follows:
If the Controller sends an instruction code which the Target cannot currently
perform because of hardware resource issues, then the Target will
acknowledge the message by echoing the invalid instruction, followed by the #
character. This response can only occur if the operator sends two or more
'hardware configuration' type commands without allowing adequate time
between commands for the hardware to be configured. For example, if the
operator issued commands to change both the frequency and the attenuation
with less than 100 milliseconds between commands, and if this response is
returned, then the command has not been accepted and the operator must
resend the command.
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Revision 3
MN-LPOD