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Two Binary Semaphores control one Task

Posted by Samuel on October 20, 2011
I am thinking one vTask control by two binary semaphores, I am not sure how to do it properly. Say one is RTCSemaphore, another is UartSemaphore, both are given from ISR. Any ISR will trigger vTask from block state to running state. Here is my idea, is there some better way to do it?

vTask(void *pVParameters)
{

for(;;)
{
if(xSemaphoreTake( RTCSemaphore, portMAX_DELAY) == pdTRUE)
{
DoRTCProcess(..);
}
else if(xSemaphoreTake( UARTSemaphore, portMAX_DELAY) == pdTRUE)
{
ProcessUartData(..);
}

}

}

RE: Two Binary Semaphores control one Task

Posted by Dave on October 20, 2011
Use a queue instead of a semaphore, and post a message to the queue that says where the message came from:

xQueueReceive( &xMessage, portMAX_DELAY )

switch( xMessage )
{
case _RTC_ : DoRTCProcess(..); break;
case _UART_: ProcessUartData(..); break;
}


Then in the interrupts use xQueueSendFromISR() instead of xSemaphoreGiveFromISR().

RE: Two Binary Semaphores control one Task

Posted by Samuel on October 21, 2011
Thanks. Your idea is better than mine.


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