RaspberyPi-ultrasonic

pi2.py

import RPi.GPIO as GPIO
import time

TRIGGER = 18
ECHO = 24

GPIO.setmode(GPIO.BCM)
GPIO.setup(TRIGGER, GPIO.OUT)
GPIO.setup(ECHO, GPIO.IN)

try:
    while True:
        GPIO.output(TRIGGER, 1)
        time.sleep(0.0001)
        GPIO.output(TRIGGER,0)

        GPIO.wait_for_edge(ECHO, GPIO.RISING)
        startTime = time.time()

        GPIO.wait_for_edge(ECHO, GPIO.FALLING)
        stopTime = time.time()

        elapsed = stopTime - startTime
        print("distance: ", (elapsed * 34300)/2, ".")
        time.sleep(1)
except KeyboardInterrupt:
    GPIO.cleanup()