1 Reply Latest reply on Sep 29, 2020 12:35 AM by HemanthR_06

    USB3 Vision DMA on Leader packet on FX3 --- 2

    user_1484456

      when the DMA is used to get pixel data of picture, its buffer has robin-round fashion. the buffer is just able to get from prod socket buffer robin-round, and put into cons socket ones by API getbuffer and commitbuffer. it is impossible to transmit leader or trailer packet with same a DMA channel. how to transmit leader and trailer to comply to U3V protocol?

       

      If the DMA channel is used in override mode, to transmit leader,payload, and trailer packet in sequence, the DMA channel has to be reset and configured for every DMA event. it is ineffective. in the meantime, the GPIF always gets pixel data continuously, to have DMA switch in different mode will cause pixel data loss.

       

      can the conclusion be drawn: for FX3014 camera solution without DDR buffer, it is impossible to implement USB3 vision camera design?

       

      If this conclusion is incorrect, how to resove these issues?how to use DMA for leader and trailer packet while DMA channel is busy in pixel data?