1 Reply Latest reply on Apr 21, 2016 4:01 AM by dhritiman.kashyap

    UVC example problem

    cycad.hsu

      Hi,

         

      I need to implement a UVC-based application. There is a FPGA before the CYUSB3014. 

         

      I find the video get stuck very often(every 2 or 3 minutes) on the AMCap. But after I restart the AMCap, the video could continue again.

         

      And I find when the video stops displaying, the uart frame count also stops increasing but the video continues streaming from FPGA to USB.

         

      What could the problem be? And what can I do (with the FPGA part or the USB firmware) to fix this issue?

         

       

         

      P.S. I find the problem is "backflow detected...", has anyone met this before? 

         

      P.P.S.  I have the same problem with the post below, do I need to create a case for technical support?

         

      http://www.cypress.com/forum/usb-30-super-speed/an75779-not-stable-all?source=search&keywords=backflow&cat=community

         

       

         

       

         

      Best Regards!

        • 1. Re: UVC example problem
          dhritiman.kashyap

          What is the interface between the FPGA and the FX3? Is it Slave FIFO? Backflow detected means that the DMA buffers in the FX3 are getting overflowed. This happens if the host is not requesting data as quickly as the buffers are getting filled. What is the host controller that you are using? Can you try with an Intel host controller. Also can you try with other UVC applications like e-CAM view.

             

          It is better to create a tech support case for such debugging.