Comtech EF Data SDM-300L3 - Manual (Page 355)

SDM-300L3 Satellite Modem Revision 1
Remote Control Operation MN/SDM300L3.IOM
A–3
A.2.3 Command/Response
The command/response portion of the message contains a variable-length character
sequence which conveys command and response data.
If a satellite modem receives a message addressed to it which does not match the established
protocol or cannot be implemented, a negative acknowledgment message is sent in
response. This message is:
>add/?ER1_parity error'cr''lf']
(Error message for received parity errors.)
>add/?ER2_invalid parameter'cr''lf']
(Error message for a recognized command which cannot be
implemented or has parameters which are out of range.)
>add/?ER3_unrecognizable
command'cr''lf']
(Error message for unrecognizable command or bad command
syntax.)
>add/?ER4_modem in local
mode'cr''lf']
(Modem in local error; send the REM command to go to remote
mode.)
>add/?ER5_hard coded
parameter'cr''lf']
(Error message indicating that the parameter is hardware dependent
and may not be changed remotely.)
Note: “add” is used to indicate a valid 1 to 3 character device address in the range
between 1 and 255.
Example: Command: <3/REM_
Response: >3/REM_