Programming languages and their editors

You program a POU in the editor for the implementation language that you have selected when you created the POU. TwinCAT 3 PLC provides a text editor for ST and graphic editors for SFC, FBD/LD/IL (textual) and CFC.

Open the editor by double-clicking on the POU in the PLC project tree or with the command Open in the context menu.

Each of the programming language editors consists of two subwindows:

The upper part is used for the declarations in the declaration editor, either in text-based or tabular form, depending on the setting.
In the lower part you insert the implementation code in the respective language.

The display and the behavior of each editor can be configured for the entire project in the corresponding tab of the TwinCAT options.

Additional information
Declaration Editor
Common Functions in Graphical Editors
Structured Text and Extended Structured Text (ExST)
Sequential Function Chart (SFC)
Function Block Diagram / Ladder / Instruction List (FBD/LD/IL)
Continuous Function Chart (CFC) and Page-Oriented CFC