* To detect a 1 or 0, it's not really necessary to detect the time.
  A bit is always composed of a LOW state of 50us, and a HIGH state
  of 26us for 0 and 70us for 1.
  So, if the HIGH state is longuer than the LOW state, it's a 1,
  otherwise it's a 0.
  This code works fine and the CRC error rate is now almost equal
  to zero. I now have to add some timeout and protections.