11 FreeRTOS Tutorial: Direct To Task Notifications part1

 

https://www.youtube.com/watch?v=Ht7QRfUvWsI&list=PLEfMFrwVdbPYzMgeaLiFRb4ogjV8m3lt6&index=12&t=0s

 

/* USER CODE BEGIN 0 */


TaskHandle_t myTask1Handle = NULL;
TaskHandle_t myTask2Handle = NULL;


void myTask1(void *pvParameters)
{

	TickType_t xDelay = pdMS_TO_TICKS(1000);
	TickType_t myLastUnblock;
	myLastUnblock = xTaskGetTickCount();


		for(;;)
		{


				xTaskNotifyGive(myTask2Handle);
				vTaskDelay(1000);
		}
}

void myTask2(void *pvParameters)
{

	TickType_t xDelay = pdMS_TO_TICKS(1000);
	TickType_t myLastUnblock;
	myLastUnblock = xTaskGetTickCount();


	char temp[10];
	int notificationValue;
    
		for(;;)
		{

			//HAL_UART_Transmit(&huart2, (uint8_t *)"\r\n",strlen("\r\n") , 10);
			notificationValue = ulTaskNotifyTake(pdTRUE, (TickType_t) portMAX_DELAY);
			//pdTrue 는 1로 정의되어 있다. 첫번째 파라미터는 0 or 1 binary 로 받는다. 0으로 설정하면 받은 value를 감소 시킨다는 의미. 1은 value를 reset 시킨다는 의미
            //하지만 notificationValue는 감소되거나 reset 되기 전의 값을 return 받는다. 즉 1을 return 받는다.


				if(notificationValue > 0){

					sprintf(temp, "%d", notificationValue);

					char* text = "notification received : ";
					HAL_UART_Transmit(&huart2, (uint8_t *)text,strlen(text) , 10);
					HAL_UART_Transmit(&huart2, (uint8_t *)temp, strlen(temp) , 10);
					HAL_UART_Transmit(&huart2, (uint8_t *)"\r\n",strlen("\r\n") , 10);


				}
		}
}

결과 : 

notification received: 1
notification received: 1
notification received: 1
notification received: 1
notification received: 1

 

 

void myTask1(void *pvParameters)
{

	TickType_t xDelay = pdMS_TO_TICKS(1000);
	TickType_t myLastUnblock;
	myLastUnblock = xTaskGetTickCount();


		for(;;)
		{

				xTaskNotifyGive(myTask2Handle);
				xTaskNotifyGive(myTask2Handle);
				xTaskNotifyGive(myTask2Handle);
				xTaskNotifyGive(myTask2Handle);
				
				vTaskDelay(5000);
 
		}
}

void myTask2(void *pvParameters)
{

	TickType_t xDelay = pdMS_TO_TICKS(1000);
	TickType_t myLastUnblock;
	myLastUnblock = xTaskGetTickCount();


	char temp[10];

		for(;;)
		{

			//HAL_UART_Transmit(&huart2, (uint8_t *)"\r\n",strlen("\r\n") , 10);
			notificationValue = ulTaskNotifyTake(pdTRUE, (TickType_t) portMAX_DELAY);
			//4번 보냈으므로 값은 4가 되고 다시 0으로 reset 되어진다. 그러므로 5초간 다시 기다리게된다.


				if(notificationValue > 0){

					sprintf(temp, "%d", notificationValue);

					char* text = "notification received : ";
					HAL_UART_Transmit(&huart2, (uint8_t *)text,strlen(text) , 10);
					HAL_UART_Transmit(&huart2, (uint8_t *)temp, strlen(temp) , 10);
					HAL_UART_Transmit(&huart2, (uint8_t *)"\r\n",strlen("\r\n") , 10);


				}
		}
}

결과 : 

notification received: 4
notification received: 4
notification received: 4
notification received: 4	
notification received: 4

 

void myTask1(void *pvParameters)
{

	TickType_t xDelay = pdMS_TO_TICKS(1000);
	TickType_t myLastUnblock;
	myLastUnblock = xTaskGetTickCount();


		for(;;)
		{

				xTaskNotifyGive(myTask2Handle);
				xTaskNotifyGive(myTask2Handle);
				xTaskNotifyGive(myTask2Handle);
				xTaskNotifyGive(myTask2Handle);
				
				vTaskDelay(5000);
 
		}
}

void myTask2(void *pvParameters)
{

	TickType_t xDelay = pdMS_TO_TICKS(1000);
	TickType_t myLastUnblock;
	myLastUnblock = xTaskGetTickCount();


	char temp[10];

		for(;;)
		{

			//HAL_UART_Transmit(&huart2, (uint8_t *)"\r\n",strlen("\r\n") , 10);
			notificationValue = ulTaskNotifyTake(pdFALSE, (TickType_t) portMAX_DELAY);
			//4가 1씩 감소하므로 4 3 2 1 순으로 출력


				if(notificationValue > 0){

					sprintf(temp, "%d", notificationValue);

					char* text = "notification received : ";
					HAL_UART_Transmit(&huart2, (uint8_t *)text,strlen(text) , 10);
					HAL_UART_Transmit(&huart2, (uint8_t *)temp, strlen(temp) , 10);
					HAL_UART_Transmit(&huart2, (uint8_t *)"\r\n",strlen("\r\n") , 10);


				}
		}
}

결과 : 

notification received: 4
notification received: 3
notification received: 2
notification received: 1	
notification received: 4