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Posted by Dennis Tan on September 3, 2009

Is it safe to call xQueuePeek inside an ISR function?


RE: xQueuePeek

Posted by MEdwards on September 3, 2009
that is an easy question, the answer is no. Only functions with FromISR in their name can be called from an interrupt.

RE: xQueuePeek

Posted by Dennis Tan on September 3, 2009
If I want to peek an item from an ISR function, how could I do it?

RE: xQueuePeek

Posted by dave m on September 4, 2009
You might have good luck by starting with the xQueueReceiveFromISR code and modifying it appropriately. I just looked at that code for the first time, so this suggestion may miss a subtle and important point, but if you leave out "--( pxQueue->uxMessagesWaiting )" and the subsequent "if(){}else{}" block, you should be pretty close.

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