End-stop being triggered twice

[Protoneer]

My issue is this: I have N/O limit switches on all axes. When one is tripped, the motion on that axis stops - as expected. However, the switch is still in the closed position when the axis movement stops. I reset and unlock via the buttons in grbl panel. When I move the axis off of the switch, when it re-opens I get another "End-Stop" event just like when it was first tripped. So for each end-stop switch closure, I am getting TWO stop events.

Is this the normal process or am I doing it wrong?

[chamnit]

@Protoneer : Hey Bertus. Yes this is normal behavior. The issue comes from the fact that the AVR processor doesn't distinguish how the pin change interrupt is triggered. It's ambiguous. Code could be created to check the state change direction, but the pin input is often bouncing. I'd have to be some robust code with a clock to check the state multiple times over time. It's an annoyance for sure, but in practice, you shouldn't be hitting the end stop too often. It'll be addressed in the next version when there is more room and extra clocks/peripherals to deal with this appropriately.