from machine import Pin, PWM
from time import sleep

buzzer = PWM(Pin(15))

def tone(freq, t):
    buzzer.duty(512)  # duty cycle = 50%
    buzzer.freq(freq)
    sleep(t)

def silent(t):
    buzzer.duty(0)
    sleep(t)

#notes = [262,294,330,349,392,440,494,524]
notes = [659, 587, 370, 415,554, 494, 294, 330,494, 440, 277, 330,440]

for n in notes :
    tone(n, 0.25)
    silent(0.1)

for i in range(len(notes)-1 , -1 , -1) :
    tone(notes[i], 0.25)
    silent(0.1)