debouncing switches with a timer interrupt?

[aratti]

This would still require some kind of debouncing. The logic state can "bounce" a number of times when pressing a button

Contact's debouncing should be solved with proper RC filter! If proper filtering is not possible an additional IF/THEN statement should reduce greatly the debouncing effect.

False        CON  0
True         CON  1
KEYPRESS  VAR portXx
KeyFlag      VAR BIT
Counter      VAR WORD

LOOP:

PAUSE 1

IF KEYPRESS = False then

IF KeyFlag = False Then
Counter = Counter + 1
KeyFlag = True
ENDIF

ELSE
KeyFlag = False
IF  KEYPRESS = False THEN  KeyFlag = True    ' re-checks the key logic state
ENDIF
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GOTO LOOP

Al.