Measuring interrupt latency?

General
1

I’d like to measure interrupt latency on a board I’m developing, but I gather that the BP5 doesn’t have any such timing measurement functions?

What I want to do is start a timer on the falling edge of pin 1 (the device’s interrupt pin in my case) and stop the timer on the falling edge of pin 2 (a gpio pin I toggle in the interrupt handler). Then ideally display the most recent time together with min/max/avg times as the measurements accumulate. Press the button to reset averages. Then I can leave it running overnight and see the max the next day, for example.

Yeah, I know I can look at some of this using logic analyzer mode, but I don’t know that sigrok has a way to accumulate measurements (have yet to try it).

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That’s really interesting. I’m sure something like that is possible with the PIO module, or even the PWM (though they lack a good capture mode, as I recall).

Logic analyzer would be good for watching a few interrupts, but doing an average overnight is a good use case for dedicated command.I can’t get to this immediately, but I have added it to my list.

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