3 Replies Latest reply on Dec 23, 2019 8:51 PM by RashiV_61

    CX3 mipi configuration Question

    KACH_4155631

      Hello

      I have a mipi configuration as below:

      2.png

      I have also call cyup3pmipicsisetpyhtimedleay to set phy delay.

      But from the oscilloscope, i sometime see the strange behavior.

      1.png

      the blue line is our mipi LV signal: data transmitted is in low.

      the yellow line is Hsync provided by CX3.

      Sometimes the hsync will not be trigger then it will cause the image data loss.

      Could you give me some debug direction?

      what is the hsync trigger start time  and end time?

      I also use dphy analyze to receive our mipi signal but it return no errors.

        • 1. Re: CX3 mipi configuration Question
          RashiV_61

          Hello,

           

          Please let me know why did you keep h blanking and v blanking field as 0. Because from the line valid trace the h blanking is not zero.

          You need to configure the CX3 receiver settings according to the sensor output.

          Please let us know the sensor output

          H active

          H_blanking

          V_active

          V_blanking

          frame/second

           

          Can you probe the sensor output (not from CX3 test pins) and share the traces (FV  LV and PCLK)

           

          Regards,

          Rashi

          • 2. Re: CX3 mipi configuration Question
            KACH_4155631

            Hello

            44.png

            Actually after setting hblank & vblank, it will change any mipi setting.

            I can't probe the sensor signal now.

            Could you just answer the below question?

            Q1:what is the hsync trigger start time  and end time on cx3 side?

            • 3. Re: CX3 mipi configuration Question
              RashiV_61

              Hello,

               

              The CX3 configuration utility should be in sync to the sensor output.The CX3 configuration utility should be exactly configured as the sensor output. Any mismatch in these two will cause improper streaming of the video (imporper FV and LV on CX3 test points). can you probe these test points on CX3? In the previous reply you mentioned the FV is from the CX3 test point

              After proper initialization of mipi communication the gpif state machine samples the video data as per the FV and LV. The CX3 has a fixed GPIF state machine which is similar to GPIF state machine mentioned in AN75779 application note https://www.cypress.com/documentation/application-notes/an75779-how-implement-image-sensor-interface-using-ez-usb-fx3-us…

               

              what is the hsync trigger start time  and end time on cx3 side?

              >> this would depend on the CX3 configuration utility settings and output from sensor.

               

              If sensor output is not same as configuration utility settings there can be problem in FV, LV generation. It would be helpful to get the traces of sensor output.

               

              Regards,

              Rashi