Create POU

Start CoDeSys and choose ‘File’ ‘New’.

In the dialog box which appears, the first POU has already been given the default name PLC_PRG. Keep this name, and the type of POU should definitely be a program. Each project needs a program with this name. In this case we choose as the language of this POU the Continuous Function Chart Editor (CFC).

Now create three more objects with the command ‘Project’ ‘Object’ ‘ Add’ with the menu bar or with the context menu (press right mouse button in the Object Organizer). A program in the language Sequential Function Chart ( Sequential Function Chart (SFC)) named SEQUENCE, a Function Block in the language Function Block Diagram ( Function Block Diagram (FBD)) named TRAFFICSIGNAL, along with a POU WAIT, also of the type function block, which we want to program as an Instruction List ( Instruction List (IL)).