Question
STM32F407 I2S High speed trouble
Posted on March 09, 2013 at 17:28
Hello peolpes,
maybe somebody can help me. For a testing I use two I2S - one(I2S3) for transmitting, second (I2S2) - for receiving, phisicaly connected at the PCB. At both I use Double Buffer DMA. I fill the sending buffer with the constant, and looking for a receiving buffer to get the same values. I use external clock at PC9 49MHz (by the way - what is the maximum alloud frequency?). At all speeds up to 96K it works fvery goood, but at 192K it totaly not work! Everytime I get a failed values in the receiving buffer, also frame error at I2S2 (receiver). I'm doing everithing according to the datasheet and errata sheet, but I thin something wrong in initialisation (maybe I forget to clear some flags?)// this is receiver r init:
void I2S2_RCV_Init(void)
{
I2S_InitTypeDef I2S2_InitStructure;
//------------------------------------------------
I2SGPIO_Init();
//
I2S_StructInit(&I2S2_InitStructure);
I2S2_InitStructure.I2S_AudioFreq =I2S_AudioFreq_Default;
I2S2_InitStructure.I2S_CPOL = I2S_CPOL_Low;
I2S2_InitStructure.I2S_Mode = I2S_Mode_SlaveRx;
I2S2_InitStructure.I2S_MCLKOutput = I2S_MCLKOutput_Disable;
I2S2_InitStructure.I2S_Standard = I2S_Standard_MSB;
I2S2_InitStructure.I2S_DataFormat = I2S_DataFormat_32b;
// wait for WS=1 the for WS=0, i.e. \_ front
WaitForWCLK(1));
WaitForWCLK(0));
I2S_Init(SPI2, &I2S2_InitStructure);
I2S2_DMA_Init();
DMA_Cmd( Rx_DMAStream, ENABLE );
I2S_Cmd(SPI2, ENABLE);
}
// WS waiting function:
static u8 WaitForWCLK(u8 edge)
{
TOTmr1ms = WCLK_TIMEOUT; // TOTmr1ms is decremented in SysTick interrupt
if(edge>0){ // wait for WCLK=1
while (0==(GPIOB->IDR & GPIO_Pin_12)){
if(TOTmr1ms==0)
return 0;
}
return 1;
}else{ // wait for WCLK=0
while (0!=(GPIOB->IDR & GPIO_Pin_12)){
if(TOTmr1ms==0)
return 0;
}
return 1;
}
}static __INLINE void I2S2_DMA_Init( void ) // ******* D M A RECEIVER ****************
{
DMA_InitTypeDef DMA_InitStruct;
NVIC_InitTypeDef NVIC_InitStructure;
DMA_Cmd( Rx_DMAStream, DISABLE );
while( DMA_GetCmdStatus( Rx_DMAStream ) == ENABLE ); // wait for the last DMA end
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);
// From:
DMA_InitStruct.DMA_PeripheralBaseAddr = (uint32_t)&(SPI2->DR); // I2S Data
// To:
DMA_InitStruct.DMA_Memory0BaseAddr = (u32)&DMARCVBUF[0][0]; // memory start
DMA_InitStruct.DMA_BufferSize = DMARCVBUF_SIZE; // length
// With parameters:
DMA_InitStruct.DMA_Channel = DMA_Channel_0;
DMA_InitStruct.DMA_DIR = DMA_DIR_PeripheralToMemory; // direction
DMA_InitStruct.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //
DMA_InitStruct.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStruct.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord; // 16 bit per
DMA_InitStruct.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord; // 16 bit memory
DMA_InitStruct.DMA_Mode = DMA_Mode_Circular; // circ
DMA_InitStruct.DMA_Priority = DMA_Priority_High; // prority
DMA_InitStruct.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStruct.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStruct.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init( Rx_DMAStream, &DMA_InitStruct ); // Init New
DMA_ITConfig( DMA1_Stream3, DMA_IT_TC, ENABLE );
DMA_DoubleBufferModeConfig(Rx_DMAStream, (uint32_t)RCVBuffer_2, DMA_Memory_0 );
DMA_DoubleBufferModeCmd( Rx_DMAStream, ENABLE );
SPI_I2S_DMACmd( SPI2, SPI_I2S_DMAReq_Rx, ENABLE);
}