TCP sockets can be used with the CJ1W-ETN21 unit with all CJ-series CPUs.

This can be extremely useful when interfacing CJ-series PLCs to 3rd-party equipment such as smart-cards readers, RFID controllers and serial-Ethernet converters.

With the CJ1W-ETN21, CJ-series PLCs can be programmed to handle TCP and UDP sockets as either Server or Client.

The sample that follows employs a CJ2-series PLC with a CJ1W-ETN21 acting as a TCP Client communicating with a Weidmuller IE-CS(T)-2TX-xRS232_485 serial-Ethernet converter set as a TCP Server (port 4001), which in turn connects to a CJ1W-SCU21 serial communcations unit behaving as a simple RS-232 device.