Play Mario on MicroPython

Welcome to the Mario Song Lab

In this lab, you will play the famous Super Mario theme song on your Pico! You will use a dictionary of note names and a list of notes to play a real melody.

How This Program Works

To play a real song, you need two things:

1. A dictionary that maps note names (like "E7") to their exact frequencies in Hz.
2. A list of note names in the order they should be played.

The program loops through the note list, looks up each frequency in the dictionary, and plays that tone.

The Mario Program

from machine import Pin, PWM  # import Pin and PWM classes
from utime import sleep        # import sleep to pause between notes

buzzer = PWM(Pin(16))          # create a PWM object on pin 16 for the buzzer

# Dictionary mapping note names to their frequencies in Hz
tones = {
"B0": 31,"C1": 33,"CS1": 35,"D1": 37,"DS1": 39,"E1": 41,"F1": 44,"FS1": 46,
"G1": 49,"GS1": 52,"A1": 55,"AS1": 58,"B1": 62,"C2": 65,
"CS2": 69,"D2": 73,"DS2": 78,"E2": 82,"F2": 87,"FS2": 93,"G2": 98,
"GS2": 104,"A2": 110,"AS2": 117,"B2": 123,"C3": 131,"CS3": 139,
"D3": 147,"DS3": 156,"E3": 165,"F3": 175,"FS3": 185,
"G3": 196,"GS3": 208,"A3": 220,"AS3": 233,"B3": 247,"C4": 262,"CS4": 277,"D4": 294,"DS4": 311,
"E4": 330,"F4": 349,"FS4": 370,"G4": 392,"GS4": 415,"A4": 440,"AS4": 466,"B4": 494,"C5": 523,"CS5": 554,"D5": 587,"DS5": 622,"E5": 659,"F5": 698,
"FS5": 740,"G5": 784,"GS5": 831,"A5": 880,"AS5": 932,"B5": 988,"C6": 1047,"CS6": 1109,"D6": 1175,"DS6": 1245,"E6": 1319,"F6": 1397,"FS6": 1480,"G6": 1568,"GS6": 1661,
"A6": 1760,"AS6": 1865,"B6": 1976,"C7": 2093,"CS7": 2217,"D7": 2349,"DS7": 2489,"E7": 2637,"F7": 2794,"FS7": 2960,"G7": 3136,"GS7": 3322,"A7": 3520,
"AS7": 3729,"B7": 3951,"C8": 4186,"CS8": 4435,"D8": 4699,"DS8": 4978
}

# A short test song
song = ["E5","G5","A5","P","E5","G5","B5","A5","P","E5","G5","A5","P","G5","E5"]

# The Mario theme melody — 0 means a rest (silence)
mario = ["E7", "E7", 0, "E7", 0, "C7", "E7", 0, "G7", 0, 0, 0, "G6", 0, 0, 0, "C7", 0, 0, "G6",
         0, 0, "E6", 0, 0, "A6", 0, "B6", 0, "AS6", "A6", 0, "G6", "E7", 0, "G7", "A7", 0, "F7", "G7",
         0, "E7", 0,"C7", "D7", "B6", 0, 0, "C7", 0, 0, "G6", 0, 0, "E6", 0, 0, "A6", 0, "B6", 0,
         "AS6", "A6", 0, "G6", "E7", 0, "G7", "A7", 0, "F7", "G7", 0, "E7", 0,"C7", "D7", "B6", 0, 0]

def play_tone(frequency):
    """Turn the buzzer on at the given frequency."""
    buzzer.duty_u16(1000)      # turn the buzzer on
    buzzer.freq(frequency)     # set the pitch

def be_quiet():
    """Turn the buzzer off (silence)."""
    buzzer.duty_u16(0)         # set duty cycle to 0 to silence the buzzer

def play_song(note_list):
    """Play every note in note_list one at a time."""
    for i in range(len(note_list)):        # loop through each position in the list
        if note_list[i] == "P" or note_list[i] == 0:
            be_quiet()                     # 0 or "P" means a rest — play silence
        else:
            play_tone(tones[note_list[i]]) # look up the frequency and play the tone
        sleep(0.3)                         # each note lasts 0.3 seconds
    be_quiet()                             # turn the buzzer off when the song ends

play_song(mario)               # play the Mario theme!

What Each Line Does

1. tones = {...} — a dictionary with over 80 note names. Each name maps to a frequency in Hz.
2. mario = [...] — a list of note names in the order they play in the melody. 0 means silence (a rest).
3. def play_tone(frequency): — a function that turns the buzzer on at a given pitch.
4. def be_quiet(): — a function that sets the duty cycle to 0, silencing the buzzer.
5. def play_song(note_list): — a function that loops through the note list and plays each one.
6. if note_list[i] == "P" or note_list[i] == 0: — checks if the current item is a rest.
7. play_tone(tones[note_list[i]]) — looks up the note name in the dictionary and plays that frequency.
8. sleep(0.3) — waits 0.3 seconds before moving to the next note.

Key Idea

The tones dictionary is the key to this program. It connects human-readable note names like "E7" to the exact frequency numbers your buzzer needs. Without it, you would have to look up every frequency by hand!

Monty's Tip

Try replacing play_song(mario) with play_song(song) to hear the short test melody first. It is much shorter and easier to check that your wiring is correct!

You Did It!

Your Pico is now playing the Mario theme song! Next, you will wire up eight buttons to build a playable piano keyboard.