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how to manage queue and semaphore

Posted by ephobb on December 28, 2015

hi, I m bit confused while implementing queue and semaphore. my scenario is as follows. I have three task. Two are from same prioirity and one is having higher prioirity. I want to send data from three task to queue. i will receive the data from queue to fourth task, where i will send data to LCD. I can't understand how to manage the queue.

xQueueHandle lcd_queue=0;

lcdqueue = xQueueCreate(20,sizeof(uint8t));

xcreate(task1,"T1",NULL,1,NULL); xcreate(task2,"T2",NULL,1,NULL); xcreate(task3,"T3",NULL,2,NULL); xcreate(Send_lcd,"LCD",NULL,1,NULL); // This task will send data to LCD and receive the data from queue.

how to manage queue and semaphore

Posted by edwards3 on December 28, 2015

Use xQueueSendToBack() to send to the queue and xQueueReceive() to receive from the queue. No need for a semaphore. http://www.freertos.org/xQueueSendToBack.html http://www.freertos.org/a00118.html

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