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multiple calls to xQueueSendFromISR

Posted by rgavrilov on January 24, 2011
I call xQueueSendFromISR twice posting to two different queues. But only one task waiting on the queue gets awaken.

__attribute__((__naked__)) static void NAME(void) {
bool taskAwaken = FALSE;
taskAwaken = xQueueSendFromISR(_queue_1, &key, taskAwaken);
taskAwaken = xQueueSendFromISR(_queue_2, &key, taskAwaken);
return taskAwaken;

if I only post to one of two queues - the corresponding task is awaken as expected.

What am I doing wrong?

I use preemptive scheduling. Port: Atmel UC3A3256

RE: multiple calls to xQueueSendFromISR

Posted by Richard Damon on January 24, 2011
While I am not familiar with that port, the signature of xQueueSendFromISR changed in Version 5 to
portBASE_TYPE xQueueSendFromISR(
xQueueHandle pxQueue,
const void *pvItemToQueue,
portBASE_TYPE *pxHigherPriorityTaskWoken
where the return value is NOT the new value of taskAwaken but a flag to indicate if the Send was successful or not., thus your lines should be (not also the adding of an & when passing taskAwaken)

flag = xQueueSendFromISR(_queue_1, &key, &taskAwaken);
flag = xQueueSendFromISR(_queue_2, &key, &taskAwaken);

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