超音波距離センサモジュールHC-SR04を制御する

hcsr04.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

def reading(sensor):
    import time
    import RPi.GPIO as GPIO
    GPIO.setwarnings(False)
    
    GPIO.setmode(GPIO.BOARD)
    TRIG = 11
    ECHO = 13
    
    if sensor == 0:
        GPIO.setup(TRIG,GPIO.OUT)
        GPIO.setup(ECHO,GPIO.IN)
        GPIO.output(TRIG, GPIO.LOW)
        time.sleep(0.3)
        
        GPIO.output(TRIG, True)
        time.sleep(0.00001)
        GPIO.output(TRIG, False)

        while GPIO.input(ECHO) == 0:
          signaloff = time.time()
        
        while GPIO.input(ECHO) == 1:
          signalon = time.time()

        timepassed = signalon - signaloff
        distance = timepassed * 17000
        return distance
        GPIO.cleanup()
    else:
        print "Incorrect usonic() function varible."
        
print reading(0)