3 Replies Latest reply on Mar 21, 2017 2:45 AM by nisa

    FX3S DMA Multicast

    andrie_2270216

      Dear all,

         

      In my application, I would like to write data from GPIF II to Storage Port and USB. I saw that to do a multicast, I have to choose a manual DMA which is much slower. As well, I would like to save as much as CPU power in order to do some other processing.

         

      So would it be possible to make 2 auto DMA channels, one from GPIF II to Storage Port and another one from GPIF II (same socket) to USB ?

         

      Best,

         

      Christian

        • 1. Re: FX3S DMA Multicast
          nisa

          You cannot create 2 DMA channels using same producer ports. for this kind of implementation you can create a GPIF to USB Manual channel., and the other CPU to S-port (the CPU is responsible to copy the same data to this channel). 

             

          The other way is to create a CY_U3P_DMA_TYPE_MULTICAST DMA channel. We have provided one example in USBBulkLoopMulticast firmware in the FX3 SDK. Please check. Let us know for further clarification.

          • 2. Re: FX3S DMA Multicast
            andrie_2270216

            Dear Nishant,

               

            Thank you for your quick response.

               

            Yes, I already saw the CY_U3P_DMA_TYPE_MULTICAST which involve to use a manual DMA channel. That is why I was asking if there was another way to work with the same producer and 2 consumers with automatic DMA channel.

               

            Would it take lots of CPU resources to do this copy from CPU to S-Port?

               

            Best,

               

            Christian

            • 3. Re: FX3S DMA Multicast
              nisa

              You cannot associate 2 channels with one port, we cannot suggest any other way to do the same. Yes, it will consume some of CPU resource, we do not have recorded/documented this data, but  it mostly depends on your application. You can check what you get in your case