FPGA VI Does Not Reset to Default Values

Updated Aug 21, 2018

Reported In


  • LabVIEW
  • LabVIEW FPGA Module

Issue Details

I call a FPGA VI from a VI running on the host using "Open FPGA VI Reference Function". When I run the application several times, the shift registers, controls and indicators of the FPGA VI are not properly reset.


Probably, the FPGA reference was not closed. At the end of the Host VI which calls the FPGA reference, this reference should also be closed using the Close FPGA VI Reference Function.
This is shown in the example VI below:

Additional Information

The VI "Close FPGA VI Reference Function" closes the reference to the FPGA VI and by default resets the VI if no other references to the VI are open. Resetting the VI returns VI controls and indicators to default states, sets global variables and uninitialized shift registers to default values, and clears FIFOs.