Other information

If you design filters again and again with Digital Filter Analyzer, sometimes it becomes unable to generate VHDL code. I guess it's due to memory's problem. So please re-start the app in that case.

Click "Refresh" if the drawing on the window looks weird.

Before you try to load coefficients, please check the radio button (FIR/IIR) on the app matches the type of filter you try to do.