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Code: Alles auswählen

#Libraries
import RPi.GPIO as GPIO
import time
 
#GPIO Mode (BOARD / BCM)
GPIO.setmode(GPIO.BCM)
 
#set GPIO Pins
GPIO_TRIGGER = 18
GPIO_ECHO = 24
 
#set GPIO direction (IN / OUT)
GPIO.setup(GPIO_TRIGGER, GPIO.OUT)
GPIO.setup(GPIO_ECHO, GPIO.IN)
 
def distance():
    # set Trigger to HIGH
    GPIO.output(GPIO_TRIGGER, True)
 
    # set Trigger after 0.01ms to LOW
    time.sleep(0.00001)
    GPIO.output(GPIO_TRIGGER, False)
 
    StartTime = time.time()
    StopTime = time.time()
 
    # save StartTime
    while GPIO.input(GPIO_ECHO) == 0:
        StartTime = time.time()
 
    # save time of arrival
    while GPIO.input(GPIO_ECHO) == 1:
        StopTime = time.time()
 
    # time difference between start and arrival
    TimeElapsed = StopTime - StartTime
    # multiply with the sonic speed (34300 cm/s)
    # and divide by 2, because there and back
    distance = (TimeElapsed * 34300) / 2
 
    return distance
 
if __name__ == '__main__':
    try:
        while True:
            dist = distance()
            print ("Measured Distance = %.1f cm" % dist)
            time.sleep(1)
 
        # Reset by pressing CTRL + C
    except KeyboardInterrupt:
        print("Measurement stopped by User")
        GPIO.cleanup()

Code: Alles auswählen

from RPi import GPIO
import time

TRIGGER_PIN = 18
ECHO_PIN = 24


def initialize():
    #GPIO Mode (BOARD / BCM)
    GPIO.setmode(GPIO.BCM)
    GPIO.setup(TRIGGER_PIN, GPIO.OUT)
    GPIO.setup(ECHO_PIN, GPIO.IN)


def measure_distance():
    GPIO.output(TRIGGER_PIN, True)
    time.sleep(0.00001)
    GPIO.output(TRIGGER_PIN, False)

    channel = GPIO.wait_for_edge(ECHO_PIN, GPIO.BOTH, timeout=200)
    if channel is None:
        print("Ultrasonic sensor timed out (pre-echo).")
        return None
    start = time.time()
          
    GPIO.wait_for_edge(ECHO_PIN, GPIO.BOTH,  timeout=400)
    if channel is None:
        print("Ultrasonic sensor timed out (post-echo).")
        return None
    stop = time.time()
   
    elapsed = stop - start
    return elapsed * 34300 / 2 # Using speed of sound at 20C


def main():
    try:
        initialize()
        while True:
            distance = measure_distance()
            print(f"Measured Distance = {distance:.1f} cm")
            time.sleep(1)
 
    except KeyboardInterrupt:
        print("Measurement stopped by User")
    finally:
        GPIO.cleanup()


if __name__ == '__main__':
    main()