Question
SAI4 on STM32H735G-DK
Hello,
I would like to use the MEMS included on this board, to learn SAI, which I never used before.
I have used STM32MxCube to setup a project.
In SAI4, SAI A, I select "Pulse Density Modulation using Microphones pairs (1-2) and CK2 as clock.
STMCube generates:
static void MX_SAI4_Init(void)
{
/* USER CODE BEGIN SAI4_Init 0 */
/* USER CODE END SAI4_Init 0 */
/* USER CODE BEGIN SAI4_Init 1 */
/* USER CODE END SAI4_Init 1 */
hsai_BlockA4.Instance = SAI4_Block_A;
hsai_BlockA4.Init.Protocol = SAI_FREE_PROTOCOL;
hsai_BlockA4.Init.AudioMode = SAI_MODEMASTER_RX;
hsai_BlockA4.Init.DataSize = SAI_DATASIZE_8;
hsai_BlockA4.Init.FirstBit = SAI_FIRSTBIT_MSB;
hsai_BlockA4.Init.ClockStrobing = SAI_CLOCKSTROBING_FALLINGEDGE;
hsai_BlockA4.Init.Synchro = SAI_ASYNCHRONOUS;
hsai_BlockA4.Init.OutputDrive = SAI_OUTPUTDRIVE_DISABLE;
hsai_BlockA4.Init.NoDivider = SAI_MASTERDIVIDER_ENABLE;
hsai_BlockA4.Init.FIFOThreshold = SAI_FIFOTHRESHOLD_EMPTY;
hsai_BlockA4.Init.AudioFrequency = SAI_AUDIO_FREQUENCY_192K;
hsai_BlockA4.Init.MonoStereoMode = SAI_STEREOMODE;
hsai_BlockA4.Init.CompandingMode = SAI_NOCOMPANDING;
hsai_BlockA4.Init.PdmInit.Activation = ENABLE;
hsai_BlockA4.Init.PdmInit.MicPairsNbr = 1;
hsai_BlockA4.Init.PdmInit.ClockEnable = SAI_PDM_CLOCK2_ENABLE;
hsai_BlockA4.FrameInit.FrameLength = 8;
hsai_BlockA4.FrameInit.ActiveFrameLength = 1;
hsai_BlockA4.FrameInit.FSDefinition = SAI_FS_STARTFRAME;
hsai_BlockA4.FrameInit.FSPolarity = SAI_FS_ACTIVE_LOW;
hsai_BlockA4.FrameInit.FSOffset = SAI_FS_FIRSTBIT;
hsai_BlockA4.SlotInit.FirstBitOffset = 0;
hsai_BlockA4.SlotInit.SlotSize = SAI_SLOTSIZE_DATASIZE;
hsai_BlockA4.SlotInit.SlotNumber = 1;
hsai_BlockA4.SlotInit.SlotActive = 0x00000000;
if (HAL_SAI_Init(&hsai_BlockA4) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN SAI4_Init 2 */
/* USER CODE END SAI4_Init 2 */
}There is nothing concerning SAI pinout in MX_GPIO_Init.
In "Clock configuration", SAI4A is set to 96MHz.
When I compile and run the project, I do not get any clock on the MEM (checked with a scope).
Other FreeRTOS tasks are running well (blinking led and USART3 logger).
Any ideas to help me ?
Olivier