Comtech EF Data CDM-600/600L - Manual (Page 197)

CDM-600/600L Open Network Satellite Modem Revision 3
Appendix D MN/CDM600L.IOM
D–5
∼
(ASCII Code 126)
The
∼ code 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.
+
(ASCII Code 43)
The + code is only used as follows:
This is similar to the = code (acknowledgement), indicating that a command has
been accepted and processed, but in addition, indicates that some other
configuration parameter has also been modified.
Example: Suppose the user has selected Viterbi + Reed-Solomon, QPSK, Rate
1/2. Now, the user changes the modulation type from QPSK to 16-QAM by
sending TMD=4. In this case, Rate 1/2 is no longer a valid code rate, and so it
will be automatically changed to the nearest valid code rate (Rate 3/4). The
Target will therefore respond with TMD+.
^
(ASCII Code 94)
The ^ code is only used as follows:
This indicates that the modem is in Remote mode, so serial remote control is not
possible. There are two exceptions to this:
•
The LRS (local/remote status) command is still active, and may be used to
change the operating mode to local or to serial remote control.
•
For the CDM-600L, the FPL (front panel lockout) command is active, and
may be used to configure the Front Panel Lockout to be “No lockout” or
“Active.”
D.5.6 Optional Message Arguments
Arguments are not required for all messages. Arguments are ASCII codes for the characters 0 to 9
(ASCII codes 48 to 57); period (ASCII code 46); and comma (ASCII code 44); plus miscellaneous
printable characters.
D.5.7 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' (ASCII code 13), and
'Line Feed' (ASCII code 10).
Both indicate the valid termination of a packet.