Goals and Symptoms
A simple example of a READ_REG function for Quantum TCP/IP communication.
Causes and Fixes
The Ethernet communications can be difficult to program using Unity, since they vary from PAC family to family. This is one of a series of example applications that presents each function block in a working version for the user to build on.
Additional Information
The attached application read_reg.zef will continuously read ten registers from another device (using the READ_REG function block). The application consists of three sections. The first is an ST section in which variables are initialized. The second section, which is the example proper, is a LD section which uses CREAD_REG function block to read 10 registers from another device, the server. This message is sent out periodically based on a timer.  The third section is another ST section that resets the timer and includes a couple of variables for debugging.
The IP address of the server is 192.168.1.30. This should be changed to suit your own addressing scheme. The application is annotated and should provide a start for the user of the CREAD_REG block. It is up to the user to change the PAC type and IP addresses to meet his or her own requirements. There is both a .zef and .xef version in the zip file.

Released for: Schneider Electric Saudi Arabia