Using Ultrasonic (HC SR-04) with Raspberry Pi
In this tutorial we will be Using Ultrasonic Sensor (SR-04) with Raspberry Pi –
Step 1 – Connections –
- Here we will be using GPIO24 as Trigger pin and GPIO25 as Echo pin.
- For this, connections will be as shown –
- We have to connect echo pin in a Voltage Divider, made by 330Ω and 470Ω as Shown.
Step 2 – Working on Code –
- Create a new file in IDLE and write the code as given
- The Code for the Following will be –
#This code is Written by Robu.in import RPi.GPIO as GPIO import time #GPIO Mode (BOARD / BCM) GPIO.setmode(GPIO.BCM) #set GPIO Pins GPIO_TRIGGER = 24 GPIO_ECHO = 25 #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()
- Now save this as python file as ultrasonic.py
- Open terminal and type command sudo python ultrasonic.py and press Enter.
- Now you will get Realtime reading by Ultrasonic Sensor on the terminal.
- You can press Ctrl+C any time to stop the program.
Hope that you would have liked it. For any Querry, you can leave a comment below : – )