Low Level I2C readByte out of sync

[SVans.1]

Hello,

I am trying to implement a low level I2C readbyte function, currently trying to read out register 0x41 (TEMP_H) and 0x42 (TEMP_L) from an MPU9250. The issue is that when I debug print the values, it seems that TEMP_H_Buffer appears to have the data from TEMP_L and vica versa (values are swapped)

Here is the function:

uint8_t I2C_readByte(I2C_TypeDef *I2Cx, uint8_t u8_registerAdress, uint8_t u8_slaveAdress, uint8_t *buffer)
{
	// Generate Write Request
	LL_I2C_HandleTransfer(I2Cx, u8_slaveAdress << 1, LL_I2C_ADDRSLAVE_7BIT, 1, LL_I2C_MODE_AUTOEND, LL_I2C_GENERATE_START_WRITE);
	while(!LL_I2C_IsActiveFlag_STOP(I2Cx))
	{
		if(LL_I2C_IsActiveFlag_TXE(I2Cx))
		{
			LL_I2C_TransmitData8(I2Cx, u8_registerAdress);
		}
	}
	LL_I2C_ClearFlag_STOP(I2Cx);
 
	//Generate Read Request
	LL_I2C_HandleTransfer(I2Cx, u8_slaveAdress << 1, LL_I2C_ADDRSLAVE_7BIT, 1, 
 LL_I2C_MODE_AUTOEND, LL_I2C_GENERATE_START_READ);
	while(!LL_I2C_IsActiveFlag_STOP(I2Cx))
	{
		if(LL_I2C_IsActiveFlag_RXNE(I2Cx))
		{
				*buffer = LL_I2C_ReceiveData8(I2Cx);
		}
	}
	LL_I2C_ClearFlag_STOP(I2Cx);
	return 0;
}

And here is the main function implementation in freeRTOS:

void Start_I2CTask(void *argument)
{
  /* USER CODE BEGIN Start_I2CTask */
  uint8_t u8_slaveAdress = 0x68;
  uint8_t TEMP_H = 0x41;
  uint8_t TEMP_L = 0x42;
  uint8_t TEMP_H_Val[] = {0};
  uint8_t TEMP_L_Val[] = {0};
  /* Infinite loop */
  uint8_t buffer[64];
  for(;;)
  {
	  //I2C_readByte(I2C_TypeDef *I2Cx, uint8_t u8_registerAdress, uint8_t u8_slaveAdress, uint8_t *buffer);
	  I2C_readByte(I2C1, TEMP_H, u8_slaveAdress, TEMP_H_Val);
 
	  sprintf(buffer, "Value in register H is : %d \n \r", TEMP_H_Val[0]);
	  HAL_UART_Transmit(&huart3, buffer, strlen(buffer), 100);
 
	  osDelay(1000);
 
	  I2C_readByte(I2C1, TEMP_L, u8_slaveAdress, TEMP_L_Val);
 
	  sprintf(buffer, "Value in register L is : %d \n \r", TEMP_L_Val[0]);
	  HAL_UART_Transmit(&huart3, buffer, strlen(buffer), 100);
 
	  osDelay(1000);
  }
  /* USER CODE END Start_I2CTask */
}

However, when I look at the serial output I see this:

Using WaveForms I capture following sequences (all seems normal to me)

TEMP_H:

TEMP_L:

 

It seems that old data from the I2C buffer is somehow transfered to the next read?

Anyone know what the issue could be?

Thanks in advance,

Sebastiaan