Declare Functions or Function Blocks

  1. Expand the PLC node in the Project Explorer and right-click on the Subprograms item.
  2. Select the action to perform (i.e., New Function or New UDFB). (Figure 1)

    3. Figure 1: Subprogram > New Function

    The New Program dialog box opens. (Figure 2)

    Figure 2: New Program dialog box

  3. Enter the program name (e.g., MyFBD) and click OK.
    The Program Properties dialog box opens. (Figure 3)

    4. Figure 3: Program Properties dialog box

  4. In either the Inputs or Outputs editable space, click the … to enable the Edit button.
    Click the Edit button or double-clicking on the editable space.
    The Parameters dialog box opens. (Figure 4)

    5. Figure 4: Parameters dialog box

Item

Description

Edit

Click this button to change the definition of the selected parameter.

When the last line (...) of the list is selected, click this button to edit a new parameter.

Delete

Click this button to remove the selected parameter.

Move Up/Down

Click these buttons to move the selected parameter in the list to arrange the order of parameters.

The order is very important because it defines the calling prototype of the UDFB or sub-program.

Swap

Click this button to move the selected parameter between the Inputs and Outputs lists.

When an button is selected the button's text changes to show where the parameter is moved.