05 USART sending and receiving data (query mode)

Modify on the basis of the first experiment .
First click on ① It's about , according to ②~⑥ Configure at ,⑦ You can keep still .

Modify after setting keil.

int main(void)
{
    
  /* USER CODE BEGIN 1 */
	char str[14] = "Hello World ";
	char recv_buf[14] = {
    0};

  /* 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_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
	HAL_UART_Transmit(&huart1, (uint8_t*)str, 12, 0xFFFF);
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
	if(HAL_OK == HAL_UART_Receive(&huart1, (uint8_t*)recv_buf, 12, 0xFFFF))
    {
    
      
      HAL_UART_Transmit(&huart1, (uint8_t*)recv_buf, 12, 0xFFFF);
    }

  }
  /* USER CODE END 3 */
}