[STM32] FreeRTOS software timer learning

 software timer

FreeRTOS provides a ready-made software timer function, which can replace the hardware timer to a certain extent, but the accuracy is not high.

Experiment: Create a task, two timers, press a button to start the timer, one prints once in 500ms, and the other prints once in 1000ms.

Implementation: Modified on the basis of [STM32] FreeRTOS event group learning .

/* USER CODE END Variables */
osThreadId Task1Handle;
osTimerId myTimer01Handle;
osTimerId myTimer02Handle;

/* Create the timer(s) */
  /* definition and creation of myTimer01 */
  osTimerDef(myTimer01, Callback01);
  myTimer01Handle = osTimerCreate(osTimer(myTimer01), osTimerPeriodic, NULL);

  /* definition and creation of myTimer02 */
  osTimerDef(myTimer02, Callback02);
  myTimer02Handle = osTimerCreate(osTimer(myTimer02), osTimerPeriodic, NULL);

  /* USER CODE BEGIN RTOS_TIMERS */

The above code is packaged by CubeMX.

Write the task code you need below.

Step 1: Modify the counting period

  /* start timers, add new ones, ... */
	xTimerChangePeriod(myTimer01Handle,500,200);
	xTimerChangePeriod(myTimer02Handle,1000,200);

Step Two: Button Tasks

void StartDefaultTask(void const * argument)
{
  /* USER CODE BEGIN StartDefaultTask */
  /* Infinite loop */
  for(;;)
  {

		if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_2)==0)
		{
			osDelay(20);
			if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_2)==0)
			{				
				printf("KEY1\r\n");
				xTimerStart(myTimer01Handle,100);
				xTimerStart(myTimer02Handle,100);
				osDelay(200);
			}
		}
		if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_2)==0)
		{
			osDelay(20);
			if(HAL_GPIO_ReadPin(GPIOE,GPIO_PIN_2)==0)
			{				
				printf("KEY2\r\n");
				xTimerStop(myTimer01Handle,100);
				xTimerStop(myTimer02Handle,100);
				osDelay(200);
			}
		}
  }
  /* USER CODE END StartDefaultTask */
}

Step 3: Timer callback

void Callback01(void const * argument)
{
  /* USER CODE BEGIN Callback01 */
	printf("Timer1\r\n");
  /* USER CODE END Callback01 */
}

/* Callback02 function */
void Callback02(void const * argument)
{
  /* USER CODE BEGIN Callback02 */
	printf("Timer2\r\n");
  /* USER CODE END Callback02 */
}