How to play piezo buzzer tunes on Raspberry Pi GPIO with PWM

1. Connect the red wire of the buzzer to GPIO Pin 5 and the black one to GPIO ground
2. Copy the following code into buzzer.py
3. Run it with this command: sudo python3 buzzer.py
4. You can also use this as a module in your robot project.

import RPi.GPIO as GPIO   #import the GPIO library
import time               #import the time library

class Buzzer(object):
 def __init__(self):
  GPIO.setmode(GPIO.BCM)  
  self.buzzer_pin = 5 #set to GPIO pin 5
  GPIO.setup(self.buzzer_pin, GPIO.IN)
  GPIO.setup(self.buzzer_pin, GPIO.OUT)
  print("buzzer ready")

 def __del__(self):
  class_name = self.__class__.__name__
  print (class_name, "finished")

 def buzz(self,pitch, duration):   #create the function “buzz” and feed it the pitch and duration)
 
  if(pitch==0):
   time.sleep(duration)
   return
  period = 1.0 / pitch     #in physics, the period (sec/cyc) is the inverse of the frequency (cyc/sec)
  delay = period / 2     #calcuate the time for half of the wave  
  cycles = int(duration * pitch)   #the number of waves to produce is the duration times the frequency

  for i in range(cycles):    #start a loop from 0 to the variable “cycles” calculated above
   GPIO.output(self.buzzer_pin, True)   #set pin 18 to high
   time.sleep(delay)    #wait with pin 18 high
   GPIO.output(self.buzzer_pin, False)    #set pin 18 to low
   time.sleep(delay)    #wait with pin 18 low

 def play(self, tune):
  GPIO.setmode(GPIO.BCM)
  GPIO.setup(self.buzzer_pin, GPIO.OUT)
  x=0

  print("Playing tune ",tune)
  if(tune==1):
    pitches=[262,294,330,349,392,440,494,523, 587, 659,698,784,880,988,1047]
    duration=0.1
    for p in pitches:
      self.buzz(p, duration)  #feed the pitch and duration to the function, “buzz”
      time.sleep(duration *0.5)
    for p in reversed(pitches):
      self.buzz(p, duration)
      time.sleep(duration *0.5)

  elif(tune==2):
    pitches=[262,330,392,523,1047]
    duration=[0.2,0.2,0.2,0.2,0.2,0,5]
    for p in pitches:
      self.buzz(p, duration[x])  #feed the pitch and duration to the function, “buzz”
      time.sleep(duration[x] *0.5)
      x+=1
  elif(tune==3):
    pitches=[392,294,0,392,294,0,392,0,392,392,392,0,1047,262]
    duration=[0.2,0.2,0.2,0.2,0.2,0.2,0.1,0.1,0.1,0.1,0.1,0.1,0.8,0.4]
    for p in pitches:
      self.buzz(p, duration[x])  #feed the pitch and duration to the func$
      time.sleep(duration[x] *0.5)
      x+=1

  elif(tune==4):
    pitches=[1047, 988,659]
    duration=[0.1,0.1,0.2]
    for p in pitches:
      self.buzz(p, duration[x])  #feed the pitch and duration to the func$
      time.sleep(duration[x] *0.5)
      x+=1

  elif(tune==5):
    pitches=[1047, 988,523]
    duration=[0.1,0.1,0.2]
    for p in pitches:
      self.buzz(p, duration[x])  #feed the pitch and duration to the func$
      time.sleep(duration[x] *0.5)
      x+=1

  GPIO.setup(self.buzzer_pin, GPIO.IN)

if __name__ == "__main__":
  a = input("Enter Tune number 1-5:")
  buzzer = Buzzer()
  buzzer.play(int(a))

Tags: python3