Comtech EF Data SMS-758 - Manual (Page 147)

SMS-758 Modem Protection Switch Remote Control Operation
MN/SMS758 Rev. 3 B–3
B.2.3 Command/Responses
The command/response portion of the message contains a variable length character
sequence which conveys command and response data.
If a modem protection switch 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_SWITCH NOT IN REMOTE MODE”cr””lf”]
(Switch not in remote error; use the MODE 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.)
•
>add/?ER6_BUSY”cr””lf”]
(Error message indicating that the command sent cannot be carried out because local processing is
utilizing the modem control bus, local keyboard, etc.)
Note: The user must select the time-out error message by selecting SW6 to be open. The
default will be closed (the bit will read low) and only responses will be returned to the
uplink. The user may select the immediate busy response by closing SW7. If SW7 is
open, the system will wait two seconds for the modem communication to become
unbusy.
B.2.4 End Character
Each message is ended with a single character which signals the end of the message:
•
“cr” Carriage return character for commands.
•
“]” End bracket for responses.