Comtech EF Data CDM-710 Installation And Operation Manual page 215

CDM-710/L Broadcast Satellite Modem
Serial Interface Operation
= (ASCII code 61)
"=" is used in two ways:
1. If the Controller sends a command to set a parameter's value, and the value is valid, the Target accepts the
command by replying with no message arguments. For example, TFQ=
2. If the Controller sends a query to a Target (for example, TFQ? means "what is the Transmit frequency?"), the
Target responds with TFQ=xxxx. xxxx, where xxxx. xxxx is the operating frequency.
? (ASCII code 63)
"?" is used when the Controller sends a command to set a parameter's value, and the value is not valid. The Target
rejects the message by echoing the valid instruction, followed by this character. For example, TFQ? (with no message
arguments)
! (ASCII code 33)
"!" is used when the Controller sends an instruction code that the Target does not recognize. The Target rejects the
message by echoing the invalid instruction, followed by this character. For example, XYZ!
* (ASCII code 42)
"*" is used when the Controller sends a command to set a parameter's value, and the value is valid but the Target
cannot permit that parameter to be changed at that time. The Target rejects the command by echoing the prohibited
instruction, followed by this character and message arguments. For example, TFQ* (with no message arguments).
# (ASCII code 35)
"#" is used when the Controller sends a correctly formatted command, but the Target is in Local Mode. The Target
rejects the command by echoing the prohibited instruction, followed by this character. For example, TFQ#
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MN/CDM710.IOM
Revision 12