1 Reply Latest reply on Jul 19, 2019 12:32 AM by KandlaguntaR_36

    Changing OV5647 frame rate

    ScGr_289066

      Hi All,

       

      I am successfully running an Omnivision OV5647 image sensor in 960p mode at 48.4 fps on the CX3 using Madhu's Streamer firmware project (FX3 / CX3 Firmware for Streaming RAW Image Data using Cypress Driver ) and a PC application I wrote using OpenCV.  I am trying to slow the frame rate which seems to only be a matter of changing the imager's PLL multiplier register (0x3036) from 100 to 52 to produce about 25 fps.

       

      When I do this and probe the sensor's MIPI stream I confirm its output frame rate has indeed dropped to 25.2 fps as expected.  Using the CX3 configuration tool to generate new settings for the reduced frame rate doesn't change any of the settings that I was using at 48.4 fps.  In fact, all of the settings in the CyU3PMipiCfg_t table for 960p remain the same, which makes sense to me since I expect the CX3's timing to be driven from the MIPI bus.

       

      The problem I see is receiving the slower frame rate never transfers any images.  Instead there is a constant stream of error 995 on the PC side.  Can someone explain what I'm missing?

       

      Thanks,

      Scott

        • 1. Re: Changing OV5647 frame rate
          KandlaguntaR_36

          Scott,

           

          >> When I do this and probe the sensor's MIPI stream I confirm its output frame rate has indeed dropped to 25.2 fps as expected.  Using the CX3 configuration tool to generate new settings for the reduced frame rate doesn't change any of the settings that I was using at 48.4 fps

           

          Since you reduced the fps, there may not any changes needed in MIPI receiver configuration. This is fine.

           

          Please do the following and confirm

           

          1. Probe the VSYNC test line and check whether it is as per 25.2 fps

          2. Confirm whether there is data flow between GPIF II producer and USB Bulk IN Endpoint

          3. Capture the USB Trace with Wireshark and check whether there is any data flow between Cx3 and host

           

          Regards,

          Sridhar