Tunnel connections can be initiated and accepted using Modem "AT" commands incoming from the Serial Line.
With Echo Pluses enabled, pluses will be echoed back during a "pause +++ pause" escape sequence on the Serial Line.
With Echo Commands enabled (ATE1), characters read on the Serial Line will be echoed while the Line is in Modem Command Mode.
With Verbose Response enabled (ATQ0), Modem Response Codes are sent out on the Serial Line.
Response Type selects either Text (ATV1) or Numeric (ATV0) representation for the Modem Response Codes sent out on the Serial Line.
With Error Unknown Commands enabled (ATU0), ERROR is returned on the Serial Line for unrecognized AT commands. Otherwise (ATU1) OK is returned for unrecognized AT commands.
Incoming Connection requests may be disabled (ATS0=0), answered automatically (ATS0=1), or answered manually via the ATA command after an incoming RING (ATS0=2).
The Connect String is a customized string that is sent to the Serial Line with the CONNECT Modem Response Code.
With Display Remote IP enabled, the incoming RING sent on the Serial Line is followed by the IP address of the caller.