Architecture

The graphical user interface is divided into three columns: the Publisher area is on the left, the Subscriber area is on the right, and the Configuration area is in the middle. When the user interface is opened, each project node contained in it is displayed graphically as an EAP device object. Each EAP device object is shown as a box in column Publisher Area and in column Subscriber Area. In other words: An EAP device object is graphically represented by two boxes.

Counting from the top, the third box in the Publisher Area represents the same EAP device as the third box in the Subscriber Area, for example. Whenever the graphical user interface is reopened, the Configuration Area is empty. A double-click on an EAP device object from one of the two other Areas results in the two corresponding boxes to be contracted and displayed in the form of a single box in the Configuration Area. The two individual boxes are then no longer displayed in the Publisher and Subscriber Areas.

The communication links are only displayed across the column borders between Publisher Area and Configuration Area and between Configuration Area and Subscriber Area. This reduced representation makes a diagnosis of the communication links between the devices more transparent.

In the Publisher Area only the Publishers of an EAP device are displayed, the structure of which is explained in section Basic principles.

In the Subscriber Area only the subscribers of an EAP device are displayed, the structure of which is explained in section Basic principles.

Initially, no EAP device object is displayed in the Configuration Area. The two corresponding boxes from the Publisher and Subscriber Areas are only brought together and displayed in the Configuration Area when an EAP device object (e.g. Device1.eap) is double-clicked with the left mouse button from one of the two other areas. The two individual boxes are then no longer displayed in the Publisher and Subscriber Areas. Only one device object at a time is displayed in the Configuration Area. In other words, double-clicking on another EAP device object in the Publisher/Subscriber Area (e.g. Device2.eap) results in Device1 being moved back from the Configuration Area to the Publisher/Subscriber Area , while Device2 is moved to the Configuration Area.

In the Configuration Area both the Publishers and the Subscribers of the EAP device are displayed. In addition, the communication links between the EAP device object displayed in the center and the EAP device objects to the left and right are displayed. All other communication links not involving the current EAP device remain invisible.

Communication link

A communication link, which leads to a data exchange between an EAP device object as source (Publisher/TxData) and an EAP device object as sink (Subscriber/RxData) based on the previously implemented configuration, is represented by an arrow from the source to the sink. A communication arrow always points from a TxData of a device object to an RxData of another device object. A communication link within an EAP device object (loop), i.e. from a TxData to an RxData of the same EAP device object, can neither be configured nor displayed. This matches the actual properties of a TwinCAT EAP device. The color of the communication arrow indicates the connection type configured by the Publisher: