Code Help Please -- Counting Button Presses

dk_akj

Hi,

This code gives me trouble.

It is supposed to count how many times pin 4 goes high.

FOR i = 1 TO 4
· DEBUG "press button x times" , DEC i,CR,LF
· COUNT 4, 25000, m_PulseCount
· DEBUG "got " , DEC m_PulseCount,CR,LF
NEXT

It counts, but it counts way to many, if i press the button 4 times it counts 8 or 10.

I have a 10K pulldown resistor on pin 4.

Can it be the button bounching ? It is the printbutton that i gor with my education board.

What can I do to solve my problem ??

//akj

Post Edited By Moderator (Jon Williams) : 8/17/2004 8:39:43 PM GMT

Chris Savage

It sounds like contact bounce is your problem...If you're trying to COUNT pulses from a mechanical device such as a pushbutton, you may want to use the BUTTON command instead.· It handles debounce, and even repeat.


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Chris Savage

Knight Designs
324 West Main Street
P.O. Box 97
Montour Falls, NY 14865
(607) 535-6777

Business Page:·· http://www.knightdesigns.com
Personal Page:··· http://www.lightlink.com/dream/chris
·

Tracy Allen

Or add an RC circuit in parallel with your switch, say C=0.1uf. That should absorb the bounce. You might have to increase the value of your pulldown resistor to 49k or 100k.

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Tracy Allen
www.emesystems.com

dk_akj

Thanks.

I'll try that.

//akj

dk_akj

Thanks,

Now it works
I'm using the button function.

//Akj