树莓派超声波测距代码

#!/usr/bin/python3import timeimport RPi.GPIO as GPIOtrigger_pin = 37echo_pin = 35GPIO.setmode(GPIO.BOARD)GPIO.setup(trigger_pin,GPIO.OUT)GPIO.setup(echo_pin,GPIO.IN)def send_trigger_pulse():    GPIO.output(trigger_pin,True)    time.sleep(0.0001)    GPIO.output(trigger_pin,False)def wait_for_echo(value,timeout):    count = timeout    while GPIO.input(echo_pin) != value and count>0:        count = count-1def get_distance():    send_trigger_pulse()    wait_for_echo(True,10000)    start = time.time()    wait_for_echo(False,10000)    finish = time.time()    pulse_len = finish-start    distance_cm = pulse_len/0.000058    return distance_cmwhile True:    print("cm = %f"%get_distance())    time.sleep(1)