xTimerStartFromISR failing?

rdpoor · October 16, 2020, 1:02pm

I have six statically allocated xTimer objects. I’m observing a call to:

BaseType_t xHigherPriorityTaskWoken = pdFALSE;
xTimerStartFromISR(handle, &xHigherPriorityTaskWoken);

is failing. Internally, the call to xQueueGenericSendFromISR() is taking this branch before returning:

traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
xReturn = errQUEUE_FULL;

I’ve not been able to figure out the cause. What should I be looking for to debug this?

rtel · October 16, 2020, 1:37pm

I think the timer command queue must be getting full. Can you increase its length and raise the priority of the timer task?

rdpoor · October 16, 2020, 4:53pm

Bingo: configTIMER_QUEUE_LENGTH was set to 2. I mistakenly assumed that statically allocated timers didn’t need to mess with the queue length. Thanks for the elucidation.