echo_location.py 文件源码

def detect_distance():
  # ??????
  GPIO.output(TRIG_CHANNEL, GPIO.HIGH)
  # ??10us??
  time.sleep(0.000015)
  GPIO.output(TRIG_CHANNEL, GPIO.LOW)

  while GPIO.input(ECHO_CHANNEL) == GPIO.LOW:
    pass
  # ???????????
  t1 = time.time()
  while GPIO.input(ECHO_CHANNEL) == GPIO.HIGH:
    pass
  # ??????????
  t2 = time.time()
  # ?????????
  return (t2-t1)*340/2