Thanks for the response.
I solved my problem by removing the FPGA reference from one of the loops. Not sure why this works.
Before I did this, the first loop would excetute once, then the second loop would excecute, never returning control to the first.
So now I have one loop that reads buttons and updates the screen, and the other loop accesses the FPGA.
This seems to work but I'm not sure why lol.
Jeff