debounce2.bas

 dim rand16 = z

 dim sw = d
 dim debounce = e
 dim jf = f
 dim cntr = g
 dim edge = h
 dim prev = i

 gosub clear

 COLUPF = $4A
 COLUBK = $42

 debounce = $00

main

 if cntr <> 32 then skip_fire

  temp1 = ((jf ^ $80) | INPT4) & $80 : jf = INPT4
  if temp1 then goto draw
  gosub clear
  cntr = 0

skip_fire
 sw = 0
 if cntr & $08 then sw = sw - 1
 temp1 = (cntr ^ $04) & $04
 if temp1 then sw = rand

 gosub debounce

 rem edge detection
 edge = (prev ^ $FF) & debounce : prev = debounce

 if cntr & $08 then pfpixel cntr 0 on
 if sw & 1 then pfpixel cntr 1 on
 if debounce & 1 then pfpixel cntr 2 on
 if edge & 1 then pfpixel cntr 3 on

 if b & 1 then pfpixel cntr 5 on
 if a & 1 then pfpixel cntr 6 on

 cntr = cntr + 1

draw
 drawscreen
 goto main




debounce
 temp1 = sw ^ debounce

 rem increment counter or reset to 11
 b = (b ^ a) | temp1
 a = (a ^ $FF) | temp1

 rem if the counter has counted to 11
 rem and 11 is not due to reset toggle debounce
 debounce = (((temp1 ^ $FF) & b) & a) ^ debounce
 return


clear
 playfield:
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end
 return