NAME

       debounce - filter noisy digital inputs

SYNOPSIS

       loadrt debounce cfg=size[,size,...]

       Creates  debounce  groups with the number of filters specified by (size).  Every filter in
       the same group has the same sample rate and delay. For example cfg=2,3 creates two  filter
       groups with 2 filters in the first group and 3 filters in the second group.

NOTE

       An  alternate  component named dbounce implements similar functionality using conventional
       count= and names= parameters.  Delay settings are implemented by  a  delay  pin  for  each
       instance instead of using filter groups.

DESCRIPTION

       The  debounce  filter  works  by  incrementing  a  counter whenever the input is true, and
       decrementing the counter when it is false.  If the counter decrements to zero, the  output
       is  set false and the counter ignores further decrements.  If the counter increments up to
       a threshold, the output is set true and the counter ignores further  increments.   If  the
       counter  is  between  zero  and the threshold, the output retains its previous state.  The
       threshold determines the amount of filtering: a threshold of 1 does no filtering  at  all,
       and  a  threshold  of  N  requires  a signal to be present for N samples before the output
       changes state.

FUNCTIONS

       debounce.G
              Sample all the input pins in group G and update the output pins.

PINS

       debounce.G.F.in bit in
              The F'th input pin in group G.

       debounce.G.F.out bit out
              The F'th output pin in group G.  Reflects the  last  "stable"  input  seen  on  the
              corresponding input pin.

       debounce.G.delay signed rw
              Sets the amount of filtering for all pins in group G.