6 Replies Latest reply on Nov 24, 2018 6:42 PM by user_205542679

    The GPIF II module customization for cx3

    user_205542679

      Dear all,

       

      I want to ask whether the GPIF II module of CX3 can be customized?  We need to modify some parameters of the state machine in the GPIF II module,

      such as  <data_count > and so on.

       

      Thanks!

       

       

        • 1. Re: The GPIF II module customization for cx3
          yyca

          Hi Viken,

           

          You could update this thread if you need us to modify the state machine and provide the header file to you.

          • 2. Re: The GPIF II module customization for cx3
            user_205542679

            Hi yyca,

            Thank you for answer.

            Please provide the header file to me。

             

             

            • 3. Re: The GPIF II module customization for cx3
              user_205542679

              Hi yyca,

               

              Is there any information showing that GPIF II interfacer's D[23:0], CLK, CTRL PINs correspond to IO of cx3?

              Can we customize GPIF module of cx3 through GPIF II Designer?

               

              Thank you very much.

              • 4. Re: The GPIF II module customization for cx3
                user_205542679

                Dear yyca,

                 

                Can you provide the reference project of CX3 in GPIF II Designer environment?

                 

                Thanks!

                • 5. Re: The GPIF II module customization for cx3
                  keaj

                  Hi,

                   

                  CX3 has a fixed GPIF II state machine and it is not recommended to modify the same.

                   

                  Can you please provide the details of your application so that we can suggest you an apt solution?

                  • 6. Re: The GPIF II module customization for cx3
                    user_205542679

                    Dear Keaj,

                     

                    With some modifications from the example firmware in SDK 1.3.4, the tested minimum vertical blanking time is reduced to about 18us without frame drop, which is improved significantly from the previous 200us.

                     

                     

                    This improvement has covered most of our applications, except one special case requiring the minimum blanking time as short as 9us. So we still try to shorten this time.

                     

                     

                    Based on the following two facts:

                    (1) The in-frame full DMA buffer is transferred smoothly to the UIB with small blanking time.

                    (2) Switching frame requires minimum blanking time as we tested as 18us.

                     

                     

                    For next step, we want to modify the GPIF state-machine to ignore the relevant states triggered by !FV(frame end), that is state 9/10/11/12 as shown in Page18 of AN75779. As such, the GPIF always switches between state0 to state8 and seems never encounter frame end. Whenever one DMA buffer is full, it is wrapped-up to CX3 RAM and then committed to UIB to transfer to host. From host side, it continuously receives DMA buffers and do frame segmentation based on buffer count.

                     

                    Can you provide the reference project of CX3 in GPIF II Designer environment?

                     

                    In conclusion, our goal is to reduce the frame interval of the firmware to <9us (the smaller the better) to adapt to the image sensor in a special mode. We look forward to your suggestions and solutions!

                     

                    Thank you very much!