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Know issue with button module V1.3 debounce code


#1

Switches need to be debounced this is normal in electronics but there seem to be a problem in the denouncing code on Spider boards.

If you subscribe to pressed and released events, you will see that you get more released events and very few pressed events! This is a problem in GHI’s denouncing code. Also, capacitor were added to latest button modules (v1.3) to help in denouncing but it seem that it did cause problems instead of helping! We will have more info/fix ASAP. But for now try the released event instead of pressed (which is fired randomly sometimes!)

You can also use the button found on the joystick module for now as well.

… please keep the feedback coming on other modules please.


#2

Right. The joystick button does not have a capacitor. I replace the cap on of of my button to 5nF instead of 100nF and it helps quite a bit. I think the current cap is too large (100nF) with a 10k pullup makes for a very large time constant. The RC circuit alone can’t debounce the switch so the cap should be there only to prevent noise to create some false triggers. A much smaller value (1nF to 10nF) should be plenty for that.


#3

Yes Correct, welcome to the community.


#4

See this http://tinyclr.com/forum/21/4373/