David VanHorn wrote:
>>
>>David,
>>
>>Your routine appears to handle only 1 switch press at a time. If you
>>want to handle multiple presses and still use debouncing, then here's an
>>AVR version of my debounce routine:
> 
> 
> 
> It does as many as you'd like.

As long as all are stable for the debounce time interval... I'm sure 
this approach is just fine for handling normal keypads. It certainly is 
efficient to have just one timer for N-switches. However, imagine you 
had one switch (or relay or whatever) that is constantly changing 
states. This unstable input prevents the debounce timer from ever 
terminating, which in turn means the other switches can not be read!

Scott
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