发送123，但是接收端收到的信息异常，求大佬指正！！

duckkeda

/* USER CODE BEGIN PV */
uint8_t buffer[5];
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{

}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
    HAL_UART_Transmit_IT(&huart1,buffer,3);
    HAL_UART_Receive_IT(&huart1,buffer,3);
}
/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
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_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
    HAL_UART_Receive_IT(&huart1,buffer,3);
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
      //HAL_UART_Transmit_IT (&huart1,(uint8_t*)"hello",5);
      
      
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}