Comtech EF Data SDM-2020 - Manual (Page 173)

SDM-2020 Satellite Modulator Revision 7
Remote Control Operation MN/SDM2020M.IOM
A-3
A.1.3 C
OMMAND
/R
ESPONSE
The command/response portion of the message contains a variable-length character
sequence, which conveys command and response data.
If a satellite modulator 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. These acknowledgment messages are:
>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.