Hi Jack,
As I understand it, you observe issue with FFT seems not having any output after you feed in the data. You are running in SignalTap. For your information, as I look into your screenshots, I notice that the "clk" seems to be remain asserted without toggling. Not sure if this is the clock for the FFT IP core? If yes, you might need to look into this to check if there is any valid clock signal into the FFT IP? thank you very much.
Apart from the clock, the other signals ie valid, ready, SOP, EOP seems to have no anomaly.
Please let me know if there is any concern. Thank you.
Best regards,
Chee Pin