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Timing of ISR

Posted by Nobody/Anonymous on September 20, 2006
I have a problem, I use a queue in an ISR, which starts a task with the highest priority. When I give the interrupt for free, the ISR starts some milliseconds after the event, which is to late!
After 3 or 4 events everything is ok, the ISR starts after some microseconds.
I use a LPC2119.
The interrupt has the second highest priority.
The highest is the timer for the os tick.

Maybe someone can help me?

RE: Timing of ISR

Posted by Nobody/Anonymous on September 20, 2006
Do you mean the ISR starts some milliseconds after some event - or that the task start some milliseconds after the ISR?

If the former, then are you keeping interrupts disabled for too long anywhere in your code?

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