//Initialize I2S subsystem for DMA circular buffer use
void ICACHE_FLASH_ATTR i2sInit() {
	int x, y;
	
	underrunCnt=0;
	
	//First, take care of the DMA buffers.
	for (y=0; y<I2SDMABUFCNT; y++) {
		//Allocate memory for this DMA sample buffer.
		i2sBuf[y]=malloc(I2SDMABUFLEN*4);
		//Clear sample buffer. We don't want noise.
		for (x=0; x<I2SDMABUFLEN; x++) {
			i2sBuf[y][x]=0;
		}
	}

	//Reset DMA
	SET_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST|SLC_TXLINK_RST);
	CLEAR_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST|SLC_TXLINK_RST);

	//Clear DMA int flags
	SET_PERI_REG_MASK(SLC_INT_CLR,  0xffffffff);
	CLEAR_PERI_REG_MASK(SLC_INT_CLR,  0xffffffff);

	//Enable and configure DMA
	CLEAR_PERI_REG_MASK(SLC_CONF0, (SLC_MODE<<SLC_MODE_S));
	SET_PERI_REG_MASK(SLC_CONF0,(1<<SLC_MODE_S));
	SET_PERI_REG_MASK(SLC_RX_DSCR_CONF,SLC_INFOR_NO_REPLACE|SLC_TOKEN_NO_REPLACE);
	CLEAR_PERI_REG_MASK(SLC_RX_DSCR_CONF, SLC_RX_FILL_EN|SLC_RX_EOF_MODE | SLC_RX_FILL_MODE);


	//Initialize DMA buffer descriptors in such a way that they will form a circular
	//buffer.
	for (x=0; x<I2SDMABUFCNT; x++) {
		i2sBufDesc[x].owner=1;
		i2sBufDesc[x].eof=1;
		i2sBufDesc[x].sub_sof=0;
		i2sBufDesc[x].datalen=I2SDMABUFLEN*4;
		i2sBufDesc[x].blocksize=I2SDMABUFLEN*4;
		i2sBufDesc[x].buf_ptr=(uint32_t)&i2sBuf[x][0];
		i2sBufDesc[x].unused=0;
		i2sBufDesc[x].next_link_ptr=(int)((x<(I2SDMABUFCNT-1))?(&i2sBufDesc[x+1]):(&i2sBufDesc[0]));
	}
	
	//Feed dma the 1st buffer desc addr
	//To send data to the I2S subsystem, counter-intuitively we use the RXLINK part, not the TXLINK as you might
	//expect. The TXLINK part still needs a valid DMA descriptor, even if it's unused: the DMA engine will throw
	//an error at us otherwise. Just feed it any random descriptor.
	CLEAR_PERI_REG_MASK(SLC_TX_LINK,SLC_TXLINK_DESCADDR_MASK);
	SET_PERI_REG_MASK(SLC_TX_LINK, ((uint32)&i2sBufDesc[1]) & SLC_TXLINK_DESCADDR_MASK); //any random desc is OK, we don't use TX but it needs something valid
	CLEAR_PERI_REG_MASK(SLC_RX_LINK,SLC_RXLINK_DESCADDR_MASK);
	SET_PERI_REG_MASK(SLC_RX_LINK, ((uint32)&i2sBufDesc[0]) & SLC_RXLINK_DESCADDR_MASK);

	//Attach the DMA interrupt
	_xt_isr_attach(ETS_SLC_INUM, (_xt_isr)slc_isr, NULL);
	//Enable DMA operation intr
	WRITE_PERI_REG(SLC_INT_ENA,  SLC_RX_EOF_INT_ENA);
	//clear any interrupt flags that are set
	WRITE_PERI_REG(SLC_INT_CLR, 0xffffffff);
	///enable DMA intr in cpu
	_xt_isr_unmask(1<<ETS_SLC_INUM);

	//We use a queue to keep track of the DMA buffers that are empty. The ISR will push buffers to the back of the queue,
	//the mp3 decode will pull them from the front and fill them. For ease, the queue will contain *pointers* to the DMA
	//buffers, not the data itself. The queue depth is one smaller than the amount of buffers we have, because there's
	//always a buffer that is being used by the DMA subsystem *right now* and we don't want to be able to write to that
	//simultaneously.
	dmaQueue=xQueueCreate(I2SDMABUFCNT-1, sizeof(int*));

	//Start transmission
	SET_PERI_REG_MASK(SLC_TX_LINK, SLC_TXLINK_START);
	SET_PERI_REG_MASK(SLC_RX_LINK, SLC_RXLINK_START);

//----

	//Init pins to i2s functions
	PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0RXD_U, FUNC_I2SO_DATA);
	PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_I2SO_WS);
#ifndef USE_ESP01_MODULE
	PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, FUNC_I2SO_BCK);
#else
	GPIO_AS_INPUT(1<<15);
	PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, FUNC_GPIO15);
#endif
	//Enable clock to i2s subsystem
	i2c_writeReg_Mask_def(i2c_bbpll, i2c_bbpll_en_audio_clock_out, 1);

	//Reset I2S subsystem
	CLEAR_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);
	SET_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);
	CLEAR_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);

	//Select 16bits per channel (FIFO_MOD=0), no DMA access (FIFO only)
	CLEAR_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN|(I2S_I2S_RX_FIFO_MOD<<I2S_I2S_RX_FIFO_MOD_S)|(I2S_I2S_TX_FIFO_MOD<<I2S_I2S_TX_FIFO_MOD_S));
	//Enable DMA in i2s subsystem
	SET_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN);

	//tx/rx binaureal
	CLEAR_PERI_REG_MASK(I2SCONF_CHAN, (I2S_TX_CHAN_MOD<<I2S_TX_CHAN_MOD_S)|(I2S_RX_CHAN_MOD<<I2S_RX_CHAN_MOD_S));

	//Clear int
	SET_PERI_REG_MASK(I2SINT_CLR,   I2S_I2S_TX_REMPTY_INT_CLR|I2S_I2S_TX_WFULL_INT_CLR|
			I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	CLEAR_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_TX_REMPTY_INT_CLR|I2S_I2S_TX_WFULL_INT_CLR|
			I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);

	//trans master&rece slave,MSB shift,right_first,msb right
	CLEAR_PERI_REG_MASK(I2SCONF, I2S_TRANS_SLAVE_MOD|
						(I2S_BITS_MOD<<I2S_BITS_MOD_S)|
						(I2S_BCK_DIV_NUM <<I2S_BCK_DIV_NUM_S)|
						(I2S_CLKM_DIV_NUM<<I2S_CLKM_DIV_NUM_S));
	SET_PERI_REG_MASK(I2SCONF, I2S_RIGHT_FIRST|I2S_MSB_RIGHT|I2S_RECE_SLAVE_MOD|
						I2S_RECE_MSB_SHIFT|I2S_TRANS_MSB_SHIFT|
						((16&I2S_BCK_DIV_NUM )<<I2S_BCK_DIV_NUM_S)|
						((7&I2S_CLKM_DIV_NUM)<<I2S_CLKM_DIV_NUM_S));


	//No idea if ints are needed...
	//clear int
	SET_PERI_REG_MASK(I2SINT_CLR,   I2S_I2S_TX_REMPTY_INT_CLR|I2S_I2S_TX_WFULL_INT_CLR|
			I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	CLEAR_PERI_REG_MASK(I2SINT_CLR,   I2S_I2S_TX_REMPTY_INT_CLR|I2S_I2S_TX_WFULL_INT_CLR|
			I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	//enable int
	SET_PERI_REG_MASK(I2SINT_ENA,   I2S_I2S_TX_REMPTY_INT_ENA|I2S_I2S_TX_WFULL_INT_ENA|
	I2S_I2S_RX_REMPTY_INT_ENA|I2S_I2S_TX_PUT_DATA_INT_ENA|I2S_I2S_RX_TAKE_DATA_INT_ENA);

	//Start transmission
	SET_PERI_REG_MASK(I2SCONF,I2S_I2S_TX_START);
}
示例#2
0
void ws2812_dma(sdio_queue_t *i2s_pixels_queue)
{
  // Reset DMA
  SET_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST);    //|SLC_TXLINK_RST);
  CLEAR_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST);  //|SLC_TXLINK_RST);

  // Clear DMA int flags
  SET_PERI_REG_MASK(SLC_INT_CLR,  0xffffffff);
  CLEAR_PERI_REG_MASK(SLC_INT_CLR,  0xffffffff);

  // Enable and configure DMA
  CLEAR_PERI_REG_MASK(SLC_CONF0,(SLC_MODE<<SLC_MODE_S));
  SET_PERI_REG_MASK(SLC_CONF0,(1<<SLC_MODE_S));
  SET_PERI_REG_MASK(SLC_RX_DSCR_CONF,SLC_INFOR_NO_REPLACE|SLC_TOKEN_NO_REPLACE);
  CLEAR_PERI_REG_MASK(SLC_RX_DSCR_CONF, SLC_RX_FILL_EN|SLC_RX_EOF_MODE | SLC_RX_FILL_MODE);

  // configure DMA descriptor
  CLEAR_PERI_REG_MASK(SLC_RX_LINK,SLC_RXLINK_DESCADDR_MASK);
  SET_PERI_REG_MASK(SLC_RX_LINK, ((uint32)i2s_pixels_queue) & SLC_RXLINK_DESCADDR_MASK);

#if WS2812_USE_INTERRUPT == 1
  // Attach the DMA interrupt
  ets_isr_attach(ETS_SLC_INUM, (int_handler_t)ws2812_isr , (void *)0);
  
  //Enable DMA operation intr
//  WRITE_PERI_REG(SLC_INT_ENA,  SLC_RX_EOF_INT_ENA);
  //clear any interrupt flags that are set
  WRITE_PERI_REG(SLC_INT_CLR, 0xffffffff);
  ///enable DMA intr in cpu
  ets_isr_unmask(1<<ETS_SLC_INUM);
#endif

  //Start transmission
  SET_PERI_REG_MASK(SLC_RX_LINK, SLC_RXLINK_START);

  //Init pins to i2s functions
  PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0RXD_U, FUNC_I2SO_DATA);

  //Enable clock to i2s subsystem
  i2c_writeReg_Mask_def(i2c_bbpll, i2c_bbpll_en_audio_clock_out, 1);

  //Reset I2S subsystem
  CLEAR_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);
  SET_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);
  CLEAR_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);

  //Select 16bits per channel (FIFO_MOD=0), no DMA access (FIFO only)
  CLEAR_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN|(I2S_I2S_RX_FIFO_MOD<<I2S_I2S_RX_FIFO_MOD_S)|(I2S_I2S_TX_FIFO_MOD<<I2S_I2S_TX_FIFO_MOD_S));
  //Enable DMA in i2s subsystem
  SET_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN);

  //trans master&rece slave,MSB shift,right_first,msb right
  CLEAR_PERI_REG_MASK(I2SCONF, I2S_TRANS_SLAVE_MOD|
            (I2S_BITS_MOD<<I2S_BITS_MOD_S)|
            (I2S_BCK_DIV_NUM <<I2S_BCK_DIV_NUM_S)|
            (I2S_CLKM_DIV_NUM<<I2S_CLKM_DIV_NUM_S));
  SET_PERI_REG_MASK(I2SCONF, I2S_RIGHT_FIRST|I2S_MSB_RIGHT|I2S_RECE_SLAVE_MOD|
            I2S_RECE_MSB_SHIFT|I2S_TRANS_MSB_SHIFT|
            (((WS_I2S_BCK-1)&I2S_BCK_DIV_NUM )<<I2S_BCK_DIV_NUM_S)|
            (((WS_I2S_DIV-1)&I2S_CLKM_DIV_NUM)<<I2S_CLKM_DIV_NUM_S));

#if WS2812_USE_INTERRUPT == 1
  //clear int
  SET_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
  CLEAR_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
  //enable int
  SET_PERI_REG_MASK(I2SINT_ENA,  I2S_I2S_RX_REMPTY_INT_ENA|I2S_I2S_RX_TAKE_DATA_INT_ENA);
#endif

  //Start transmission
  SET_PERI_REG_MASK(I2SCONF,I2S_I2S_TX_START);
  
}
示例#3
0
//Initialize I2S subsystem for DMA circular buffer use
void ICACHE_FLASH_ATTR ws2812_init()
{
	int x, y;
	
	//Reset DMA
	SET_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST);//|SLC_TXLINK_RST);
	CLEAR_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST);//|SLC_TXLINK_RST);

	//Clear DMA int flags
	SET_PERI_REG_MASK(SLC_INT_CLR,  0xffffffff);
	CLEAR_PERI_REG_MASK(SLC_INT_CLR,  0xffffffff);

	//Enable and configure DMA
	CLEAR_PERI_REG_MASK(SLC_CONF0, (SLC_MODE<<SLC_MODE_S));
	SET_PERI_REG_MASK(SLC_CONF0,(1<<SLC_MODE_S));
	SET_PERI_REG_MASK(SLC_RX_DSCR_CONF,SLC_INFOR_NO_REPLACE|SLC_TOKEN_NO_REPLACE);
	CLEAR_PERI_REG_MASK(SLC_RX_DSCR_CONF, SLC_RX_FILL_EN|SLC_RX_EOF_MODE | SLC_RX_FILL_MODE);

	i2sBufDescOut.owner = 1;
	i2sBufDescOut.eof = 1;
	i2sBufDescOut.sub_sof = 0;
	i2sBufDescOut.datalen = WS_BLOCKSIZE;  //Size (in bytes)
	i2sBufDescOut.blocksize = WS_BLOCKSIZE; //Size (in bytes)
	i2sBufDescOut.buf_ptr=(uint32_t)&i2sBlock[0];
	i2sBufDescOut.unused=0;
	i2sBufDescOut.next_link_ptr=(uint32_t)&i2sBufDescZeroes; //At the end, just redirect the DMA to the zero buffer.

	i2sBufDescZeroes.owner = 1;
	i2sBufDescZeroes.eof = 1;
	i2sBufDescZeroes.sub_sof = 0;
	i2sBufDescZeroes.datalen = 32;
	i2sBufDescZeroes.blocksize = 32;
	i2sBufDescZeroes.buf_ptr=(uint32_t)&i2sZeroes[0];
	i2sBufDescZeroes.unused=0;
	i2sBufDescZeroes.next_link_ptr=(uint32_t)&i2sBufDescOut;


	for( x = 0; x < 32; x++ )
	{
		i2sZeroes[x] = 0x00;
	}
	for( x = 0; x < WS_BLOCKSIZE/4; x++ )
	{
		i2sBlock[x] = 0x00000000;//(x == 0 || x == 999)?0xaa:0x00;
	
/*		uint16_t * tt = (uint16_t*)&i2sBlock[x];
		(*(tt+0)) = 0xA0F0;
		(*(tt+1)) = 0xC0E0;*/

	}


//	CLEAR_PERI_REG_MASK(SLC_TX_LINK,SLC_TXLINK_DESCADDR_MASK);
//	SET_PERI_REG_MASK(SLC_TX_LINK, ((uint32)&i2sBufDescZeroes) & SLC_TXLINK_DESCADDR_MASK); //any random desc is OK, we don't use TX but it needs something valid

	CLEAR_PERI_REG_MASK(SLC_RX_LINK,SLC_RXLINK_DESCADDR_MASK);
	SET_PERI_REG_MASK(SLC_RX_LINK, ((uint32)&i2sBufDescOut) & SLC_RXLINK_DESCADDR_MASK);

#ifdef USE_2812_INTERRUPTS

	//Attach the DMA interrupt
	ets_isr_attach(ETS_SLC_INUM, slc_isr);
	//Enable DMA operation intr
	WRITE_PERI_REG(SLC_INT_ENA,  SLC_RX_EOF_INT_ENA);
	//clear any interrupt flags that are set
	WRITE_PERI_REG(SLC_INT_CLR, 0xffffffff);
	///enable DMA intr in cpu
	ets_isr_unmask(1<<ETS_SLC_INUM);

#endif

	//Start transmission
//	SET_PERI_REG_MASK(SLC_TX_LINK, SLC_TXLINK_START);
	SET_PERI_REG_MASK(SLC_RX_LINK, SLC_RXLINK_START);

//----

	//Init pins to i2s functions
	PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0RXD_U, FUNC_I2SO_DATA);
//	PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_I2SO_WS);
//	PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, FUNC_I2SO_BCK);

	//Enable clock to i2s subsystem
	i2c_writeReg_Mask_def(i2c_bbpll, i2c_bbpll_en_audio_clock_out, 1);

	//Reset I2S subsystem
	CLEAR_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);
	SET_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);
	CLEAR_PERI_REG_MASK(I2SCONF,I2S_I2S_RESET_MASK);

	//Select 16bits per channel (FIFO_MOD=0), no DMA access (FIFO only)
	CLEAR_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN|(I2S_I2S_RX_FIFO_MOD<<I2S_I2S_RX_FIFO_MOD_S)|(I2S_I2S_TX_FIFO_MOD<<I2S_I2S_TX_FIFO_MOD_S));
	//Enable DMA in i2s subsystem
	SET_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN);

	//tx/rx binaureal
//	CLEAR_PERI_REG_MASK(I2SCONF_CHAN, (I2S_TX_CHAN_MOD<<I2S_TX_CHAN_MOD_S)|(I2S_RX_CHAN_MOD<<I2S_RX_CHAN_MOD_S));

#ifdef USE_2812_INTERRUPTS

	//Clear int
	SET_PERI_REG_MASK(I2SINT_CLR,  
			I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	CLEAR_PERI_REG_MASK(I2SINT_CLR, 
			I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);

#endif

	//trans master&rece slave,MSB shift,right_first,msb right

	CLEAR_PERI_REG_MASK(I2SCONF, I2S_TRANS_SLAVE_MOD|
						(I2S_BITS_MOD<<I2S_BITS_MOD_S)|
						(I2S_BCK_DIV_NUM <<I2S_BCK_DIV_NUM_S)|
						(I2S_CLKM_DIV_NUM<<I2S_CLKM_DIV_NUM_S));
	SET_PERI_REG_MASK(I2SCONF, I2S_RIGHT_FIRST|I2S_MSB_RIGHT|I2S_RECE_SLAVE_MOD|
						I2S_RECE_MSB_SHIFT|I2S_TRANS_MSB_SHIFT|
						(((WS_I2S_BCK-1)&I2S_BCK_DIV_NUM )<<I2S_BCK_DIV_NUM_S)|
						(((WS_I2S_DIV-1)&I2S_CLKM_DIV_NUM)<<I2S_CLKM_DIV_NUM_S));


	//No idea if ints are needed...
	//clear int
	SET_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	CLEAR_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	//enable int
	SET_PERI_REG_MASK(I2SINT_ENA,  I2S_I2S_RX_REMPTY_INT_ENA|I2S_I2S_RX_TAKE_DATA_INT_ENA);


	//Start transmission
	SET_PERI_REG_MASK(I2SCONF,I2S_I2S_TX_START);
}
C3WireOutput::C3WireOutput(
		unsigned int nLength,
		unsigned int nBck,
		unsigned int nDiv,
		I3WireEncoder *pEncoder)
	: COutput(nLength)
{
	// Final clock frequency is:
	// 160 / MAX(2, nBck) / MAX(2, nDiv)
	//
	// Example:
	// For the WS2811 800khz clock,
	// one bit should take 1.25usec or 1250nanosec
	//   1sec/1250nanosec = 800khz
	// Assuming we need 4 bits to encode each bit, we'd need a clock of
	//   4 * 800khz = 3.2mhz
	// So we need to find 160 / nBck / nDiv = 3.2
	//   160 / 3.2 = 50
	// So we need nBck * nDiv = 50, where nBck>=2 and nDiv>=2
	//   We should use 5 and 10, or 2 and 25, etc
	m_pEncoder = pEncoder;
	m_nBufferLength = m_pEncoder->getMaxLength(m_nLength);
	m_pBuffer = new uint32_t[m_nBufferLength];

	memset(&m_qBuffer, 0, sizeof(m_qBuffer));
	memset(&m_qZeroes, 0, sizeof(m_qZeroes));
	memset(m_pZeroes, 0, sizeof(m_pZeroes));

	// DMA buffer structure.
	// Buffer points to actual data, zeroes points to zeroes
	// Both buffer and zeroes point to zeroes as "next buffer"
	m_qBuffer.owner = m_qZeroes.owner = 1;
	m_qBuffer.eof = m_qZeroes.eof = 1;
	m_qBuffer.sub_sof = m_qZeroes.sub_sof = 0;
	m_qBuffer.datalen = m_qBuffer.blocksize = m_nBufferLength * sizeof(uint32_t);
	m_qZeroes.datalen = m_qZeroes.blocksize = sizeof(m_pZeroes);
	m_qBuffer.buf_ptr = (uint32_t)m_pBuffer;
	m_qZeroes.buf_ptr = (uint32_t)m_pZeroes;
	m_qBuffer.unused = m_qZeroes.unused = 0;
	m_qBuffer.next_link_ptr = m_qZeroes.next_link_ptr = (uint32_t)&m_qZeroes;

	// Pin func select
	PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0RXD_U, FUNC_I2SO_DATA);
	// We don't really care about anything other than data,
	// But you might want to un-comment these while debugging.
	// PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_I2SO_WS);
	// PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, FUNC_I2SO_BCK);

	//Reset DMA
	SET_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST);
	CLEAR_PERI_REG_MASK(SLC_CONF0, SLC_RXLINK_RST);

	//Clear DMA int flags
	SET_PERI_REG_MASK(SLC_INT_CLR, 0xFFFFFFFF);
	CLEAR_PERI_REG_MASK(SLC_INT_CLR, 0xFFFFFFFF);

	//Enable and configure DMA
	CLEAR_PERI_REG_MASK(SLC_CONF0, (SLC_MODE << SLC_MODE_S));
	SET_PERI_REG_MASK(SLC_CONF0, (1<<SLC_MODE_S));
	SET_PERI_REG_MASK(SLC_RX_DSCR_CONF, SLC_INFOR_NO_REPLACE|SLC_TOKEN_NO_REPLACE);
	CLEAR_PERI_REG_MASK(SLC_RX_DSCR_CONF, SLC_RX_FILL_EN|SLC_RX_EOF_MODE|SLC_RX_FILL_MODE);

	CLEAR_PERI_REG_MASK(SLC_RX_LINK, SLC_RXLINK_DESCADDR_MASK);
	SET_PERI_REG_MASK(SLC_RX_LINK, ((uint32_t)&m_qZeroes) & SLC_RXLINK_DESCADDR_MASK);

	SET_PERI_REG_MASK(SLC_RX_LINK, SLC_RXLINK_START);

	//Clock provider?
	i2c_writeReg_Mask_def(i2c_bbpll, i2c_bbpll_en_audio_clock_out, 1);

	// Reset I2S subsystem
	CLEAR_PERI_REG_MASK(I2SCONF, I2S_I2S_RESET_MASK);
	SET_PERI_REG_MASK(I2SCONF, I2S_I2S_RESET_MASK);
	CLEAR_PERI_REG_MASK(I2SCONF, I2S_I2S_RESET_MASK);

	CLEAR_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN|(I2S_I2S_RX_FIFO_MOD<<I2S_I2S_RX_FIFO_MOD_S)|(I2S_I2S_TX_FIFO_MOD<<I2S_I2S_TX_FIFO_MOD_S));
	SET_PERI_REG_MASK(I2S_FIFO_CONF, I2S_I2S_DSCR_EN);

	//Trans master & rece slave?

	CLEAR_PERI_REG_MASK(I2SCONF, I2S_TRANS_SLAVE_MOD|
						(I2S_BITS_MOD<<I2S_BITS_MOD_S)|
						(I2S_BCK_DIV_NUM <<I2S_BCK_DIV_NUM_S)|
						(I2S_CLKM_DIV_NUM<<I2S_CLKM_DIV_NUM_S));
	SET_PERI_REG_MASK(I2SCONF, I2S_RIGHT_FIRST|I2S_MSB_RIGHT|I2S_RECE_SLAVE_MOD|
						I2S_RECE_MSB_SHIFT|I2S_TRANS_MSB_SHIFT|
						(((nBck)&I2S_BCK_DIV_NUM )<<I2S_BCK_DIV_NUM_S)|
						(((nDiv)&I2S_CLKM_DIV_NUM)<<I2S_CLKM_DIV_NUM_S));

	//No idea if ints are needed...
	//clear int
	SET_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	CLEAR_PERI_REG_MASK(I2SINT_CLR, I2S_I2S_RX_WFULL_INT_CLR|I2S_I2S_PUT_DATA_INT_CLR|I2S_I2S_TAKE_DATA_INT_CLR);
	//enable int
	SET_PERI_REG_MASK(I2SINT_ENA,  I2S_I2S_RX_REMPTY_INT_ENA|I2S_I2S_RX_TAKE_DATA_INT_ENA);


	//Start transmission
	SET_PERI_REG_MASK(I2SCONF,I2S_I2S_TX_START);
}