[DemoCode下载] PDMA传递I2S

// Configure PDMA to Scatter Gather mode */

void PDMA_Init(void)

{

    /* Tx description */

    DMA_TXDESC[0].ctl = ((BUFF_LEN-1)<<PDMA_DSCT_CTL_TXCNT_Pos)|PDMA_WIDTH_32|PDMA_SAR_INC|PDMA_DAR_FIX|PDMA_REQ_SINGLE|PDMA_OP_SCATTER;

    DMA_TXDESC[0].src = (uint32_t)&PcmTxBuff[0];

    DMA_TXDESC[0].dest = (uint32_t)&I2S0->TXFIFO;

    DMA_TXDESC[0].offset = (uint32_t)&DMA_TXDESC[1] - (PDMA->SCATBA);



    DMA_TXDESC[1].ctl = ((BUFF_LEN-1)<<PDMA_DSCT_CTL_TXCNT_Pos)|PDMA_WIDTH_32|PDMA_SAR_INC|PDMA_DAR_FIX|PDMA_REQ_SINGLE|PDMA_OP_SCATTER;

    DMA_TXDESC[1].src = (uint32_t)&PcmTxBuff[1];

    DMA_TXDESC[1].dest = (uint32_t)&I2S0->TXFIFO;

    DMA_TXDESC[1].offset = (uint32_t)&DMA_TXDESC[0] - (PDMA->SCATBA);   //link to first description



    /* Rx description */

    DMA_RXDESC[0].ctl = ((BUFF_LEN-1)<<PDMA_DSCT_CTL_TXCNT_Pos)|PDMA_WIDTH_32|PDMA_SAR_FIX|PDMA_DAR_INC|PDMA_REQ_SINGLE|PDMA_OP_SCATTER;

    DMA_RXDESC[0].src = (uint32_t)&I2S0->RXFIFO;

    DMA_RXDESC[0].dest = (uint32_t)&PcmRxBuff[0];

    DMA_RXDESC[0].offset = (uint32_t)&DMA_RXDESC[1] - (PDMA->SCATBA);



    DMA_RXDESC[1].ctl = ((BUFF_LEN-1)<<PDMA_DSCT_CTL_TXCNT_Pos)|PDMA_WIDTH_32|PDMA_SAR_FIX|PDMA_DAR_INC|PDMA_REQ_SINGLE|PDMA_OP_SCATTER;

    DMA_RXDESC[1].src = (uint32_t)&I2S0->RXFIFO;

    DMA_RXDESC[1].dest = (uint32_t)&PcmRxBuff[1];

    DMA_RXDESC[1].offset = (uint32_t)&DMA_RXDESC[0] - (PDMA->SCATBA);   //link to first description



    /* Open PDMA channel 1 for I2S TX and channel 2 for I2S RX */

    PDMA_Open(PDMA,0x3 << 1);



    /* Configure PDMA transfer mode */

    PDMA_SetTransferMode(PDMA,1, PDMA_I2S0_TX, 1, (uint32_t)&DMA_TXDESC[0]);

    PDMA_SetTransferMode(PDMA,2, PDMA_I2S0_RX, 1, (uint32_t)&DMA_RXDESC[0]);



    /* Enable PDMA channel 1&2 interrupt */

    PDMA_EnableInt(PDMA,1, 0);

    PDMA_EnableInt(PDMA,2, 0);



    NVIC_EnableIRQ(PDMA_IRQn);

}

    /* Open I2S0 interface and set to slave mode, stereo channel, I2S format */

    I2S_Open(I2S0, I2S_MODE_SLAVE, 16000, I2S_DATABIT_16, I2S_DISABLE_MONO, I2S_FORMAT_I2S);



    /* Set PE.13 low to enable phone jack on NuMaker board. */

    SYS->GPE_MFPH &= ~(SYS_GPE_MFPH_PE13MFP_Msk);

    GPIO_SetMode(PE, BIT13, GPIO_MODE_OUTPUT);

    PE13 = 0;



    // select source from HXT(12MHz)

    CLK_SetModuleClock(I2S0_MODULE, CLK_CLKSEL3_I2S0SEL_HXT, 0);



    /* Set MCLK and enable MCLK */

    I2S_EnableMCLK(I2S0, 12000000);