Paris-based Schneider Electric has introduced a derived function block code that enables a programmable logic controller (PLC) to communicate easily with third-party transmission control protocol (TCP) devices, including radio frequency tag readers, printers, bar code readers and even other PLCs. Named TCP Open, the code was developed for the company’s Modicon Premium controller.
The new radio frequency identification (RFID) standards established by Wal-Mart and the U.S. Department of Defense require suppliers shipping goods to track them by case and pallet. This new programming tool allows consumer packaged goods manufacturers, as well as anyone now required to track shipments, to easily connect and communicate information from RFID tags.
The function blocks in Schneider Electric’s Telemecanique TCP Open create an object in an object-oriented programming environment. The object automatically opens an Ethernet communication channel to an RF tag reader, records the data and then closes the channel. The code block can be installed in a PLC’s programming software in minutes, Schneider says. It enables the programmer to construct a protocol within the application layer, allowing the PLC to communicate directly with any third-party device that is equipped with Ethernet TCP/IP.
