stm32h7b3i-dk SAI1 configuration

[AmrithHN]

Hi,

I am trying to use SAI instead of I2S6 since the BDMA seems to not trigger even after proper configuration.

I am using SAI for the first time so I am completely unsure about this config:

/**
  * @brief SAI1 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_SAI1_Init(void)
{

  /* USER CODE BEGIN SAI1_Init 0 */

  /* USER CODE END SAI1_Init 0 */

  /* USER CODE BEGIN SAI1_Init 1 */

  /* USER CODE END SAI1_Init 1 */
  hsai_BlockA1.Instance = SAI1_Block_A;
  hsai_BlockA1.Init.AudioMode = SAI_MODEMASTER_TX;
  hsai_BlockA1.Init.Synchro = SAI_ASYNCHRONOUS;
  hsai_BlockA1.Init.OutputDrive = SAI_OUTPUTDRIVE_DISABLE;
  hsai_BlockA1.Init.NoDivider = SAI_MASTERDIVIDER_ENABLE;
  hsai_BlockA1.Init.FIFOThreshold = SAI_FIFOTHRESHOLD_1QF;
  hsai_BlockA1.Init.AudioFrequency = SAI_AUDIO_FREQUENCY_22K;
  hsai_BlockA1.Init.SynchroExt = SAI_SYNCEXT_DISABLE;
  hsai_BlockA1.Init.MonoStereoMode = SAI_STEREOMODE;
  hsai_BlockA1.Init.CompandingMode = SAI_NOCOMPANDING;
  hsai_BlockA1.Init.TriState = SAI_OUTPUT_NOTRELEASED;
  if (HAL_SAI_InitProtocol(&hsai_BlockA1, SAI_I2S_STANDARD, SAI_PROTOCOL_DATASIZE_16BIT, 2) != HAL_OK)
  {
    Error_Handler();
  }
  hsai_BlockB1.Instance = SAI1_Block_B;
  hsai_BlockB1.Init.AudioMode = SAI_MODESLAVE_RX;
  hsai_BlockB1.Init.Synchro = SAI_SYNCHRONOUS;
  hsai_BlockB1.Init.OutputDrive = SAI_OUTPUTDRIVE_DISABLE;
  hsai_BlockB1.Init.FIFOThreshold = SAI_FIFOTHRESHOLD_1QF;
  hsai_BlockB1.Init.SynchroExt = SAI_SYNCEXT_DISABLE;
  hsai_BlockB1.Init.MonoStereoMode = SAI_STEREOMODE;
  hsai_BlockB1.Init.CompandingMode = SAI_NOCOMPANDING;
  hsai_BlockB1.Init.TriState = SAI_OUTPUT_NOTRELEASED;
  if (HAL_SAI_InitProtocol(&hsai_BlockB1, SAI_I2S_STANDARD, SAI_PROTOCOL_DATASIZE_16BIT, 2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN SAI1_Init 2 */

  /* USER CODE END SAI1_Init 2 */

}

DMA seems to be working and I am getting a values of around 65000 , so I suspect the audio driver or SAI configuration is wrong.

I have taken some portion of the audio driver from the stm32 repo . I was unsure how to use the driver also It gave me some errors when I included it in my build  (some functions had same name as the CubeMx generated ones).

I2C in the driver works and I confirmed this by reading the ID from the Codec. I can read and write registers . So I have created few functions to setup MIC and start it.

SAI configuration is shown above , and DMA was also configured using the GUI . which seems to work and read some values but these values are either close to zero or close to 65000 all the time.

[MOBEJ]

Hello @AmrithHN ,

Your issue could stem from several sources. Please check the following:

1. GPIO Configuration for SAI:

   • Ensure that the GPIOs used for SAI are properly configured. Note that the GPIOs for SAI are different from those used for I2S.
   • If you are using CubeMX, verify that the configuration is correct.

2. SAI1 Clock Source Configuration:

   • Confirm that the SAI1 clock source is correctly configured. In CubeMX, you need to set a clock source around 11.422 MHz to achieve an FS frequency of 22.050 KHz after SAI clock division. You can use one of the PLLs for this purpose.

3. Driver Implementation:

   • It appears that you have developed a new driver similar to the CS42L51 driver component. If possible, I recommend using the existing CS42L51 driver in your software to avoid issues with function name conflicts.
   • You can find an example of the CS42L51 driver usage (without BSP) in the SAI_AudioPlay example for the STM32H7B3I-EVAL. You can use the same functions with the same parameters, except for codec_init.InputDevice, which should be set to CS42L51_IN_MIC1 before calling AudioDrv->Init(AudioCompObj, &codec_init).

BR

[AmrithHN]

Thank You so much for checking this out.

I am really new to SAI or I2S in general , I think the clock configuration is the issue.

I will try using the existing drivers, problem was its having too much abstractions and uses multiple files to configure so it wasnt easy to understand .

Thank you so much !

Regards

Amrith

[AmrithHN]

"SAI_AudioPlay example for the STM32H7B3I-EVAL" has only one SAI block A configured as Master TX this should work for sending data, to get data from Codec SAI1_SD_B (block B) should be configured as slave receiver right?