An instance of this service interface function block type encapsulates an instance of the JButton class to provide a GUI (Graphic User Interface) pushbutton for the user to enter an event occurrence into an IEC 61499 function block network through the IND output of the function block. The LABEL input provides a label for the pushbutton. Propagation of the event through the IND output is inhibited when the QI input is false.

The operation of an instance of this class is modeled by the service sequences shown below.