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_USART2_UART_Init();
MX_TIM1_Init();
/* USER CODE BEGIN 2 */
HAL_TIM_Base_Start(&htim1);
HAL_GPIO_WritePin(TRIG_PORT, TRIG_PIN, GPIO_PIN_RESET); // pull the TRIG pin low
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
HAL_GPIO_WritePin(TRIG_PORT, TRIG_PIN, GPIO_PIN_SET); // pull the TRIG pin HIGH
__HAL_TIM_SET_COUNTER(&htim1, 0);
while (__HAL_TIM_GET_COUNTER (&htim1) < 100); // wait for 100 us
HAL_GPIO_WritePin(TRIG_PORT, TRIG_PIN, GPIO_PIN_RESET); // pull the TRIG pin low
pMillis = HAL_GetTick(); // used this to avoid infinite while loop (for timeout)
// wait for the echo pin to go high
while (!(HAL_GPIO_ReadPin (ECHO_PORT, ECHO_PIN)) && pMillis + 10 > HAL_GetTick());
Value1 = __HAL_TIM_GET_COUNTER (&htim1);
pMillis = HAL_GetTick(); // used this to avoid infinite while loop (for timeout)
// wait for the echo pin to go low
while ((HAL_GPIO_ReadPin (ECHO_PORT, ECHO_PIN)) && pMillis + 50 > HAL_GetTick());
Value2 = __HAL_TIM_GET_COUNTER (&htim1);
Distance = (Value2 - Value1)* 0.034/2;
char buffer[20];
sprintf(buffer, "Distance: %d cm\r\n", Distance);
HAL_UART_Transmit(&huart2, (uint8_t*)buffer, strlen(buffer), HAL_MAX_DELAY);
HAL_Delay(50);
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
