Efficient switch polling

[qtommer]

I am polling 3 TACT switches in a continuous loop using a MCU. Should a switch be asserted, the worst case delay that the switch has to wait for the program to poll it again is 14us. Is there any sort of RC arrangement I can apply to the switch to hold the value (once asserted) for at least 14us so that the MCU can receive it without any possibility of 'missing' the switch input.

I know 14us is very short, but I want the reading of the switches to be as smooth and efficient as possible.

Thanks

 

[Diver300]

To avoid noise and switch bounce, 14 µs is too short.

I would count at least 100 times that, and probably 1000 times, so 14 ms or more, before I registered the switch as being pressed. I would also apply the same on release.

It will still seem instant to the user.

 

[qtommer]

There was flickering of the output (on an LED) when it was too short. The contact of the button when pressed was way longer than the program execution. I added a delay in between and everything's sweet now. Thanks!