2018.4.44

2018.4.44

# 超声波测距函数
def distance():
    GPIO.output(TRIG, 0)
    time.sleep(0.000002)
    GPIO.output(TRIG, 1)
    time.sleep(0.00001)
    GPIO.output(TRIG, 0)
    while GPIO.input(ECHO) == 0:
        pass
    emitTime = time.time()
    while GPIO.input(ECHO) == 1:
        pass
    acceptTime = time.time()
    totalTime = acceptTime - emitTime
    distanceForReturn = totalTime * 340 / 2 * 100
    return  distanceForReturn