TCP Serial Client

When the RS-232 port is configured as TCP Serial Client, the NL200/201 will initiate and maintain a TCP socket connection to the IP address and port number specified by the Serial Client Address and Serial Client Port settings. Data received on the RS-232 port will be forwarded to this TCP connection, and data received on the TCP connection will be forwarded to the RS-232 port. This mode can be particularly useful when an RF base or serial sensor is behind a firewall and needs to be the party responsible for initiating the TCP socket connection to the data collection server.

The NL200/201 will attempt to open a connection with the remote server, and, if the connection fails to open, the device will continue to retry at an interval of 60 seconds. If data arrives on the RS-232 port when no TCP connection exists, the device will buffer the data (up to 1500 bytes) and immediately attempt to open a connection to deliver the data. If the remote server closes the connection due to error, the NL200/201 will make a best effort to save any data that was in process and re-queue it to be sent on the next successfully-opened TCP connection.