6 Replies Latest reply on Nov 15, 2015 11:54 PM by relac_1052361

    FX3 UVC Example AN75779 Application



      I want to change the firmware provided in AN75779.zip  to meet the requirement of my own sensor with the following features:


      1. 16-bit synchronous parallel data interface


      2. 16 bits per pixel


      3. YUY2 color space


      4. 1024 * 768 pixel resolution


      5. 30 frames per second


      6. Active high frame/line valid signals


      7. Positive clock edge polarity


      Most of those features are same as the sensor used in AN75779,except 1 and 4, width of the data interface and resolution.


      For 16-bit synchronous parallel data interface, I go to the Interface Definition tab in GPIF II Designer and choose the 16 Bit option for Data Bus Width, then i go to the state machine tab, change the counter limit value of LD_DATA_COUNT and LD_ADDR_COUNT to 8183.Finally, i update the cyfxgpif2config.h in original firmware project,and make sure the iomatrix configuration in the firmware has the isDQ32Bit parameter set to CyFalse.


      For 1024 * 768 pixel resolution, I change the related content of descriptors as follow,


              /* Class specific Uncompressed VS format descriptor */
              0x04,                           /* X dimension of the picture aspect ratio; Non-interlaced */
              0x03,                           /* Y dimension of the pictuer aspect ratio: Non-interlaced */


             /* Class specific Uncompressed VS frame descriptor */
              0x00, 0x04,                     /* Width in pixel */
              0x00, 0x03,                     /* Height in pixel */


      The remain part of the firmware is unchanged.


      My sensor is not configured through FX3, but i am sure it could run in the expected mode described above.After all, I build the firmware project and download the .img file into FX3 and preview real-time video use software like AMCap/VirtualDub, the system could work, show clear image with the set resolution, but it just streams near 15 frames per second, and even worse is that, the frame rate drops to 0 fps after a few seconds, the video is getting stuck.The video could be recovered by restarting the software,but then it stucks again after a few seconds.


      I need help.Thanks!