1 Reply Latest reply on Jun 18, 2019 10:15 PM by KandlaguntaR_36

    Simultaneous bulk-in and controlep communication on Superspeed USB

    ScGr_289066

      Hi All,

       

      I have adapted the streamer app firmware to stream raw10 (Bayer) video to the PC and written an OpenCV PC application to display it.  The firmware and PC app together have some issues.  At 5Mp resolution, the video streams only for a minute or two before PC error 31 pops up.  After this error firmware must be reloaded to resume operation.  At 1080p, the system runs reliably, but images are sometimes not correctly framed.  That is multiple frames appear in the same image as I have show.

       

       

      The framing is intermittent.  While working on the PC, browsing, text editing, etc. The partial frames will shift in the video window.  Stopping and restarting imaging will sync the frames with the window until the next random shift happens.

       

      As part of the device's control, I have implemented commands that I send to the control endpoint and receive in the CX3 firmware to control various aspects of the device's operation.  Unfortunately, any time I send any of these commands video is disrupted for several seconds.  I saw this related white paper (https://community.cypress.com/docs/DOC-10848) but the proposed solution will disrupt video just as much as sending commands now does, so this isn't really a solution.  Is there a solution to this problem?  I would point out that the UVC driver doesn't have these issues.  One can use the built-in camera control and change camera parameters without disrupting camera video.

       

      Thanks,

      Scott