Placing SubVIs on Block Diagrams

After you build a VI and create its icon and connector pane, you can use the VI in another VI. A VI used by another VI is called a subVI. A subVI node corresponds to a subroutine call in text-based programming languages. The node is not the subVI itself, just as a subroutine call statement in a program is not the subroutine itself.

Complete the following steps to place a subVI on the block diagram.

  1. Display the block diagram of a new or existing VI by selecting Window»Show Diagram.
  2. If necessary, display the Functions palette by selecting Window»Show Functions Palette.
  3. Select Functions»Select a VI.
  4. Navigate to and double-click the VI you want to use as a subVI, and place it on the block diagram.
  5. Wire the subVI terminals to other nodes on the block diagram.
Note  If the subVI does not have a connector pane, you cannot wire the subVI to other nodes.

You can double-click the subVI node to display the front panel of the subVI.

You also can place an open VI on the block diagram of another open VI. Use the Positioning tool to click the icon in the upper right corner of the front panel or block diagram of the VI you want to use as a subVI, and drag it to the block diagram of the other VI.