2 Replies Latest reply on Jul 11, 2012 7:25 AM by rama.sai.krishna.vakkantula

    GPIF 16 Bit Master mode

    h.deboer@tiepie.nl
        • 1. Re: GPIF 16 Bit Master mode
          h.deboer@tiepie.nl

          Hello, everyone

             

          I try to send a buffer containing words (16 bit data) through endpoint 1 to the gpif interface via DMA. The gpif interface is configured in 16 bit master mode.The lsb appears on dq[0] to dq[7] and a clock cycle later appears it msb also on dq[0] to dq[7] . Dq[8] to dq[15] are always zero. If I change the Endianness from little to big then both the msb and lsb appear on dq[8] to dq[15] and dq[0] to dq[7] are always zero. This is not what I want, I want to sent the lsb to dq[0] t/m dq[7] and the msb to dq[8] to dq[15].Someone any idea what I am doing wrong? Maybe the DMA also has to be configured to use words?

             

          Thanks

          • 2. Re: GPIF 16 Bit Master mode
            rama.sai.krishna.vakkantula

             Please make sure that you have configured IO matrix correctly in the firmware.

               

             

               

            io_cfg.isDQ32Bit = CyFalse;

               

            io_cfg.lppMode   = CY_U3P_IO_MATRIX_LPP_UART_ONLY;    /*GPIF 16-bit and UART only*/

               

             

               

            Regards,

               

            sai krishna.