With CODESYS it is possible to run multiple applications on one target device. This example shows how to create child applications and how to run multiple applications on one control.

Technical description:

The project MultipleApplication contains two main applications: MainApplication1 and MainApplication2.

As an example, a simple 2-point-regulator with a corresponding visualization is used.

The visualization and the data structure are stored in the POU pool. The communication between the applications is done over the global variable list of the main application.

The IO mapping must always be defined in the main application.

Example MainApplication1:

The main application contains the visualization of two regulators. The logic of the regulators is outsourced in ChildApplication1 and ChildApplication2. Both applications can be started independently. This architecture is useful, if a controller process must run independently from other processes.

Example MainApplication2:

In this example, the main application contains the regulator logic. The visualization is outsourced in a child application (VisuApplication). This architecture is useful, if a controller process must run independently from the visualization.