My I2C communication in DMA mode is not working properly

[Mabou.1]

Hello,

I have developed two codes to test the I2C communication between a master device (STM32F411RE) and a slave device (also STM32F411RE) in DMA mode. The expected result is as follows: whenever there is a rising or falling edge interruption on GPIO_PIN_11 of the master device, it should send a TX buffer to the slave device. After receiving the buffer by the slave device, master device should enter the reception mode for I2C and wait for a response from the slave.

On the slave device, I have initially set it to the reception mode for I2C. Once the first buffer sent by the master is received by the slave, it waits for 1 seconds before switching to the transmission mode to send a response back to the master. I am using a button connected to GPIO pin 11 to generate the interruptions.

The result that I get is when I trigger the first interruption on the master device, it successfully sends the buffer to the slave, and the slave accurately receives the buffer. However, I am not receiving any response from the slave device afterward.

My master code

int main(void)
{
  /* USER CODE BEGIN 1 */
 
  /* USER CODE END 1 */
 
  /* MCU Configuration--------------------------------------------------------*/
 
  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();
 
  /* USER CODE BEGIN Init */
 
  /* USER CODE END Init */
 
  /* Configure the system clock */
  SystemClock_Config();
 
  /* USER CODE BEGIN SysInit */
 
  /* USER CODE END SysInit */
 
  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_I2C1_Init();
  /* USER CODE BEGIN 2 */
 
  /*for(int i = 1; i<20; i++){
	  ret = HAL_I2C_IsDeviceReady(&hi2c1, i, 3, 100);
	  if(ret == HAL_OK){
		  uint8_t address = i;
	  }
	  while(HAL_I2C_GetState(&hi2c1) != HAL_I2C_STATE_READY){
 
	  }
  }*/
  txbuffer[0] = 0x01;
  txbuffer[1] = 0xFF;
  txbuffer[2] = 0x05;
  txbuffer[3] = 0xFF;
  txbuffer[4] = 0xFF;
  txbuffer[5] = 0xFF;
  txbuffer[6] = 0xFF;
  txbuffer[7] = 0xFF;
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
	  while (1)
	  {
	    /* USER CODE END WHILE */
 
		  if(RXflag == true){
			if(HAL_I2C_Master_Receive_DMA(&hi2c1, 16, rxbuffer, sizeof(rxbuffer)) != HAL_OK)
			{
				/* Transfer error in reception process */
				Error_Handler();
			}
			RXflag = false;
		  }
 
		  if(TXflag == true){
			if(HAL_I2C_Master_Transmit_DMA(&hi2c1, 16, txbuffer, sizeof(txbuffer)) != HAL_OK)
			{
				/* Transfer error in transmission process */
				Error_Handler();
			}
			TXflag = false;
		  }
	/* USER CODE BEGIN 3 */
	  }
  /* USER CODE END 3 */
}
 
void HAL_I2C_MasterTxCpltCallback(I2C_HandleTypeDef*hi2c)
{
	RXflag = true;
}
 
void HAL_I2C_MasterRxCpltCallback(I2C_HandleTypeDef*hi2c)
{
	TXflag = true;
}
 
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
	switch(GPIO_Pin){
	case GPIO_PIN_11:
		HAL_I2C_Master_Transmit_DMA(&hi2c1, 16, (uint8_t *)txbuffer, sizeof(txbuffer));
		break;
 
	case GPIO_PIN_12:
			break;
 
	default:
		break;
	}
}

My Slave code

int main(void)
{
  /* USER CODE BEGIN 1 */
 
  /* USER CODE END 1 */
 
  /* MCU Configuration--------------------------------------------------------*/
 
  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();
 
  /* USER CODE BEGIN Init */
 
  /* USER CODE END Init */
 
  /* Configure the system clock */
  SystemClock_Config();
 
  /* USER CODE BEGIN SysInit */
 
  /* USER CODE END SysInit */
 
  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_I2C1_Init();
  HAL_I2C_MspInit(&hi2c1);
  /* USER CODE BEGIN 2 */
 
  if(HAL_I2C_Slave_Receive_DMA(&hi2c1, rxbuffer, sizeof(rxbuffer)) != HAL_OK)
  {
    /* Transfer error in reception process */
    Error_Handler();
  }
 
  txbuffer[0] = 11;
  txbuffer[1] = 12;
  txbuffer[2] = 13;
  txbuffer[3] = 14;
  txbuffer[4] = 15;
  txbuffer[5] = 16;
  txbuffer[6] = 17;
  txbuffer[7] = 18;
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
	/* USER CODE END WHILE */
	  if(RXflag == true){
		if(HAL_I2C_Slave_Receive_DMA(&hi2c1, rxbuffer, sizeof(rxbuffer)) != HAL_OK)
		{
			/* Transfer error in reception process */
			Error_Handler();
		}
		RXflag = false;
	  }
 
	  if(TXflag == true){
		HAL_Delay(1000);
		if(HAL_I2C_Slave_Transmit_DMA(&hi2c1, txbuffer, sizeof(txbuffer)) != HAL_OK)
		{
			/* Transfer error in transmission process */
			Error_Handler();
		}
		TXflag = false;
	  }
 
	/* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}
 
void HAL_I2C_SlaveTxCpltCallback(I2C_HandleTypeDef *I2cHandle)
{
	HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET);
	RXflag = true;
}
 
void HAL_I2C_SlaveRxCpltCallback(I2C_HandleTypeDef *hi2c)
{
	TXflag = true;
	if(rxbuffer[0] == 0x01)
	{
		HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_SET);
	}
}

[Foued_KH]

Hello @Mabou.1​ ,

Try to set breakpoint and debug your code. Take an oscilloscope to check the I2C_SDA and I2C_SCL behavior.

If you are facing some erratic behavior on STM32, do not forget to check Errata sheet of the device. There are few points related to I2C interface. 

Foued

[Mabou.1]

Hello,

I have observed that for the slave device to provide a response to the master, it needs to enter the transmission mode before the master device enters the reception mode. However, this poses a challenge for me because in my scenario, the slave device must respond after varying durations, such as 500ms or 2 seconds, depending on the specific data buffer received from the master.

Any ideas how can I get this work properly ?

[Foued_KH]

 Run the Controller before run the Target, this will let a false startup phase on Target side

 as there is no high level on the bus, if the Target is started before the Controller.

Foued

[Foued_KH]

You can also check the I2C available examples on the CubeFW : STM32Cube_FW_F4_V1.27.1\Projects\STM32F410xx-Nucleo\Examples\I2C\I2C_TwoBoards_ComDMA

This example has been tested with STM32F4xx-Nucleo RevC board and can be easily tailored to any other supported device and development board. 

Foued

[Mabou.1]

Yes, I have already reviewed various examples, but I haven't found a solution that can fix my problem.