Hi,
I'm working with self designed board (STM32F765 MCU) and currently able to initialize SAI2 peripheral to work with codec in DMA mode.
At some point in my code, I need to change the sample rate of my codec (through MCLK).
The sequence of operations is basically as follows:
//1. DeInit SAI
HAL_SAI_DeInit(&hsai_BlockB2); //Deinit SAI_MODEMASTER_TX block set at old AudioFrequency
HAL_SAI_DeInit(&hsai_BlockA2); //Deinit SAI_MODESLAVE_RX block
//2 Init SAI with new freq. SAI_AUDIO_FREQUENCY_96K
hsai_BlockA2.Instance = SAI2_Block_A;
hsai_BlockA2.Init.AudioMode = SAI_MODESLAVE_RX;
hsai_BlockA2.Init.Synchro = SAI_SYNCHRONOUS;
hsai_BlockA2.Init.OutputDrive = SAI_OUTPUTDRIVE_DISABLE;
hsai_BlockA2.Init.FIFOThreshold = SAI_FIFOTHRESHOLD_1QF;
hsai_BlockA2.Init.SynchroExt = SAI_SYNCEXT_DISABLE;
hsai_BlockA2.Init.MonoStereoMode = SAI_STEREOMODE;
hsai_BlockA2.Init.CompandingMode = SAI_NOCOMPANDING;
hsai_BlockA2.Init.TriState = SAI_OUTPUT_NOTRELEASED;
if (HAL_SAI_InitProtocol(&hsai_BlockA2, SAI_I2S_STANDARD, SAI_PROTOCOL_DATASIZE_16BIT, 2) != HAL_OK)
{
Error_Handler();
}
hsai_BlockB2.Instance = SAI2_Block_B;
hsai_BlockB2.Init.AudioMode = SAI_MODEMASTER_TX;
hsai_BlockB2.Init.Synchro = SAI_ASYNCHRONOUS;
hsai_BlockB2.Init.OutputDrive = SAI_OUTPUTDRIVE_ENABLE;
hsai_BlockB2.Init.NoDivider = SAI_MASTERDIVIDER_ENABLE;
hsai_BlockB2.Init.FIFOThreshold = SAI_FIFOTHRESHOLD_1QF;
hsai_BlockB2.Init.AudioFrequency = SAI_AUDIO_FREQUENCY_96K;
hsai_BlockB2.Init.SynchroExt = SAI_SYNCEXT_DISABLE;
hsai_BlockB2.Init.MonoStereoMode = SAI_STEREOMODE;
hsai_BlockB2.Init.CompandingMode = SAI_NOCOMPANDING;
hsai_BlockB2.Init.TriState = SAI_OUTPUT_NOTRELEASED;
if (HAL_SAI_InitProtocol(&hsai_BlockB2, SAI_I2S_STANDARD, SAI_PROTOCOL_DATASIZE_16BIT, 2) != HAL_OK)
{
Error_Handler();
}
//3 custom function that reinit codec
Codec_Init();
//4. restart DMA tx and rx
if(HAL_OK != HAL_SAI_Transmit_DMA(&hsai_BlockB2, (uint8_t *)txAddr, Size))
{
Error_Handler();
}
if(HAL_OK != HAL_SAI_Receive_DMA(&hsai_BlockA2, (uint8_t *)rxAddr, Size))
{
Error_Handler();
}
The problem arises inside HAL_SAI_Transmit_DMA(&hsai_BlockB2, (uint8_t *)txAddr, Size), at the following :
if (HAL_DMA_Start_IT(hsai->hdmarx, (uint32_t)&hsai->Instance->DR, (uint32_t)hsai->pBuffPtr, hsai->XferSize) != HAL_OK)
the system goes in:
Default_Handler:
Infinite_Loop:
b Infinite_Loop
.size Default_Handler, .-Default_Handler
The sequence of operations is the same at the start (working) and when I try to set the new frequency (not working) except for:
hsai_BlockB2.Init.AudioFrequency = SAI_AUDIO_FREQUENCY_8K; (working case)
hsai_BlockB2.Init.AudioFrequency = SAI_AUDIO_FREQUENCY_96K; (not working case)
I checked PeriphClkInitStruct settings and are ok for both cases.
I also verified that if I start directly by setting the frequency to 96k everything works; so it seems like something related to the reinitialization operation.
Thanks in advance for the support.
