Comtech EF Data CDM-710G, Installation And Operation Manual

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CDM-710G High-Speed Satellite Modem Revision 1
Remote Control MN-CDM710G
A–4
2. From Target to Controller , the only permitted values are:
=
(ASCII code 61)
The = code (target to controller) is used in two ways:
First , if the controller has sent a query code to a target ( for example: TFQ?,
meaning ‘ what is the Transmit frequency? ’), the target would respond with
TFQ=xxxx.xxxx, where xxxx.xxxx represents the frequency in question.
Second , 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 TFQ= (with no message arguments).
?
(ASCII code 63)
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 TFQ? (with no message arguments).
This indicates that there was an error in the message sent by the controller.
!
(ASCII code 33)
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.
Example: XYZ!
*
(ASCII code 42)
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 TFQ* (with no message arguments).
#
(ASCII code 35)
The # code (target to controller) is only used as follows:
If the controller sends a correctly formatted command, BUT the modem is not in
remote mode, it will not allow reconfiguration, and will respond with TFQ#.
∼
(ASCII Code 126)
The
∼
code (target to controller) is only used as follows:
If a message was sent via a local modem to a distant end device or ODU, the
message was transmitted transparently through the local modem. In the event of
the distant-end device not responding, the local modem would generate a
response.
Example: 0001/RET ~ , indicating that it had finished waiting for a
response and was now ready for further comms.
A.5.5 Message Arguments
Arguments are not required for all messages. Arguments are ASCII codes for the characters 0 to
9 (ASCII 48 to 57), period (ASCII 46) and comma (ASCII 44).
A.5.6 End Of Packet
Controller to Target: This is the ‘Carriage Return’ character (ASCII code 13).
Target to Controller: This is the two-character sequence ‘Carriage Return’, ‘Line Feed’. (ASCII
code 13, and code 10.) Both indicate the valid termination of a packet.