'Athena Logic Probe

  const TestLead 0
  const OutputLED 10
  const PulsePin 2

  input TestLead
  output OutputLED
  output PulsePin
 
  dim state,laststate
  dim testhigh,testlow

   clear testhigh
   clear testlow
 
'-------------------------------------------
'Main program loop
loop:


  gosub testhighlow
  if laststate <> state then
     gosub havepulse
  else
     laststate = state
  endif
 


   branch state,itslow,itsnone,itshigh

   goto loop


itsnone:
   high OutputLED
   goto loop

itslow:
   low OutputLED
   pauseus 25 'Light it only for a few us
   high OutputLED
   goto loop

itshigh:
   low OutputLED 'Turn LED on
   goto loop


'-------------------------------------------------------
havepulse:
  laststate = state
  low OutputLED
  signal 9,25,20
  high OutputLED
  signal 9,25,20
  return

'-------------------------------------------------------
testhighlow:
   high PulsePin
   portbitget testhigh,0,TestLead
   low PulsePin
   portbitget testlow,0,TestLead
   state = testhigh + testlow
   return