Comtech EF Data XPA-200-OD - Manual (Page 17)

XPA-200-OD Revision 1
Customer Commands MN/XPA200OD.IOM
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First, if the controller has sent a query code to a target (for example MUT?, meaning ‘is
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,
providing 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 (target to controller) is only used as follows:
If the controller sends an instruction to set a parameter to a particular value, and, if the
value sent in the argument is not valid, then 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 (target to controller) is only used as follows:
If the controller sends an instruction to set a parameter to a particular value, and, if the
value sent in the argument is valid, however the target is in the wrong mode (e.g., standby
mode in redundancy configuration) that it will not permit that particular parameter to be
changed at that time, then 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 does not recognize, then the
target will acknowledge the message by echoing the invalid instruction, followed by the !
character with. Example: XYZ!
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 excepted and the operator must resend the
command.