Comtech EF Data CDM-570A User Manual
Page 246

CDM-570A/570AL Satellite Modem with Optional Packet Processor
MN-CDM570A
Serial-based Remote Product Management
Revision 2
8–6
? (ASCII Code 63)
If the Controller issues a command to set a parameter to a particular value, and the value sent is not valid, the Target then
acknowledges the message and responds with ‘?’. This indicates that there was an error in the message sent by the Controller.
For example: >0000/TFQ? (with no message arguments).
! (ASCII Code 33)
If the Controller issues a command that the Target does not recognize, the Target responds by echoing the invalid instruction code,
followed by ‘!’.
For example: >0000/ABC!
* (ASCII Code 42)
If the Controller issues a command to set a parameter to a particular value, and the value sent is valid, but the modem will not permit
that particular parameter to be changed at present, the Target responds by echoing the valid instruction code, followed by ‘*’.
For example: >0000/TFQ* (with message arguments)
# (ASCII Code 35)
If the Controller sends a correctly formatted command, but the Target is not in Remote Mode, the unit does not allow reconfiguration
and responds by echoing the valid instruction code, followed by ‘#’.
For example: >0000/TFQ#
~ (ASCII Code 126)
If a message is 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 wil generate a response.
For example: >0000/RET~ (indicating that it has finished waiting for a response and is now ready for further comms).