Reading FPGA VI Indicators

Complete the following steps to read an indicator in an FPGA VI from a host VI.

  1. Open a reference to the FPGA VI or bitfile.
    Note   The FPGA target, FPGA VI, and host VI must be in the same LabVIEW project if you want to open a reference to an FPGA VI. The host VI does not need to be in a project if you open a reference to a bitfile.
  2. Add the Read/Write Control function to the block diagram. Notice that the Read/Write Control function contains one Unselected input.
  3. Wire the FPGA VI Reference Out parameter of the Open FPGA VI Reference function or the Bitfile reference out parameter of the Open Dynamic Bitfile Reference function to the FPGA VI Reference In parameter of the Read/Write Control function.
  4. Click the Unselected input. The shortcut menu lists all front panel controls and indicators in the FPGA VI in the Controls submenu.
    Note   If the FPGA VI is not saved, or does not have any controls or indicators, this list is empty.
  5. Select an indicator available in the FPGA VI from the shortcut menu. Notice that the Unselected input changes to an output and reflects the name of the indicator in the FPGA VI.

To read more indicators in the FPGA VI, right-click the Read/Write Control function and select Add Element from the shortcut menu and then customize the output as described in the previous step. You also can click the bottom line of the Read/Write Control function with the Positioning tool and drag the line down to add more controls and indicators. The read and write operations execute sequentially from top to bottom. Also, if the FPGA VI has subVIs and you want to access controls and indicators on the subVI, you must wire the subVI controls and indicators to the controls and indicators of the FPGA VI that is used in the Open FPGA VI Reference function.

Note   You also can read FPGA VI controls. To read a control, right-click the control input on the Read/Write Control function and select Change to Read from the shortcut menu.