💡 Level 1 – Fundamentals

Project 1.5: "Musical Buzzer"

🚀 Project 1.5 – Musical Buzzer

🎯 What You’ll Learn

✅ Goal 1: Play tones with a passive buzzer.
✅ Goal 2: Perform scales and simple melodies.
✅ Goal 3: Control frequency by code and create personalized songs.

Key Ideas

music.MIDI: Special block for buzzer control.
pitch_time: Generates a tone with frequency and duration.
play: Plays predefined melodies.

🧱 Blocks Glossary (used in this project)

music.MIDI(pin): Initializes buzzer on the given pin.
midi.pitch_time(freq, ms): Plays a tone at frequency (Hz) for duration (ms).
midi.play(melody): Plays a predefined melody.
Delay: Controls note duration.

🧰 What You Need

Part	How many?	Pin connection
D1 R32	1	USB cable
Passive Buzzer	1	Pin 26 → GND

🔌 Wiring tip: Connect buzzer long leg to Pin 26, short leg to GND.
📍 Pin map snapshot: Pin 26 = buzzer control.

✅ Before You Start

USB cable connected
Buzzer wired correctly
Test print:

print("Ready!")  # Confirm serial is working

🎮 Microprojects (5 Mini Missions)

🎮 Microproject 1.5.1 – Single tone

Goal: Play one tone.
Blocks used: music.MIDI, pitch_time
Block sequence:

Initialize buzzer on pin 26
Play tone 440 Hz for 1000 ms

MicroPython Code:

import music                                # Import special library for buzzer
midi = music.MIDI(26)                       # Initialize buzzer on pin 26

midi.pitch_time(440, 1000)                  # Play tone at 440 Hz for 1000 ms
print("Tone: 440 Hz for 1s")                # Serial: show current tone

🎮 Microproject 1.5.2 – Basic musical scale

Goal: Play C major scale.
Blocks used: music.MIDI, pitch_time, for loop
Block sequence:

Define list of frequencies
Play each tone for 500 ms

MicroPython Code:

import music
midi = music.MIDI(26)                       # Initialize buzzer on pin 26

scale = [262, 294, 330, 349, 392, 440, 494, 523]  # Frequencies for C major scale

for freq in scale:                          # Loop through each frequency
    midi.pitch_time(freq, 500)              # Play tone for 500 ms
    print("Tone:", freq, "Hz")              # Serial: show current tone

🎮 Microproject 1.5.3 – Melody “Happy Birthday”

Goal: Play a simple melody.
Blocks used: music.MIDI, pitch_time, for loop
Block sequence:

Define notes and durations
Play sequence

MicroPython Code:

import music
midi = music.MIDI(26)                       # Initialize buzzer on pin 26

melody = [(264,300),(264,300),(297,600),(264,600),(352,600),(330,1200)]  # Simplified notes

for note, dur in melody:                    # Loop through each note
    midi.pitch_time(note, dur)              # Play note with duration
    print("Note:", note, "Hz for", dur, "ms")  # Serial: show current note

🎮 Microproject 1.5.4 – Frequency control by code

Goal: Change tone frequency dynamically.
Blocks used: music.MIDI, pitch_time, for loop
Block sequence:

Loop from 200 Hz to 800 Hz
Increase step by step

MicroPython Code:

import music
midi = music.MIDI(26)                       # Initialize buzzer on pin 26

for freq in range(200, 801, 100):           # Frequencies from 200 to 800 Hz
    midi.pitch_time(freq, 500)              # Play tone for 500 ms
    print("Tone:", freq, "Hz")              # Serial: show current tone

🎮 Microproject 1.5.5 – Personalized melody

Goal: Create your own melody.
Blocks used: music.MIDI, pitch_time, for loop
Block sequence:

Define custom list of notes
Play sequence

MicroPython Code:

import music
midi = music.MIDI(26)                       # Initialize buzzer on pin 26

my_song = [(392,400),(440,400),(494,400),(523,800)]  # Custom melody

for note, dur in my_song:                   # Loop through each note
    midi.pitch_time(note, dur)              # Play note with duration
    print("Note:", note, "Hz for", dur, "ms")  # Serial: show current note

✨ Main Project – Musical Buzzer

🔧 Blocks Steps (with glossary)

music.MIDI: Initialize buzzer.
pitch_time: Generate tones with frequency and duration.
Loop: Play sequence of notes.

Block sequence:

Setup buzzer on pin 26
Define melody
Loop through notes

🐍 MicroPython Code (mirroring blocks)

# Project 1.5 – Musical Buzzer

import music                                # Import special library
midi = music.MIDI(26)                       # Initialize buzzer on pin 26

melody = [(264,300),(264,300),(297,600),(264,600),(352,600),(330,1200)]  # Happy Birthday

for note, dur in melody:                    # Loop through each note
    midi.pitch_time(note, dur)              # Play note with duration
    print("Note:", note, "Hz for", dur, "ms")  # Serial: show current note

📖 External Explanation

What it teaches: How to generate music with a buzzer.
Why it works: music.MIDI controls the buzzer, pitch_time changes frequency and duration.
Key concept: Frequency + duration + repetition = melody.

✨ Story Time

Your robot is now a musician 🎶. It can play scales, famous songs, and even your own compositions.

🕵️ Debugging (2 Common Problems)

🐞 Debugging 1.5.A – No sound (incorrect pin)

Problem: Buzzer is silent.
Clues: Wrong pin used.
Broken code:

midi = music.MIDI(2)   # Wrong pin

Fixed code:

midi = music.MIDI(26)  # Correct pin

Why it works: The buzzer is wired to pin 26.
Avoid next time: Always check wiring and pin number.

🐞 Debugging 1.5.B – Distorted tone

Problem: Strange or noisy sound.
Clues: Frequency or duration set incorrectly.
Broken code:

midi.pitch_time(50, 10)   # Very low frequency and too short duration

Fixed code:

midi.pitch_time(440, 500) # Standard frequency and proper duration

Why it works: Correct values produce a clear tone.
Avoid next time: Use common musical frequencies (200–1000 Hz).

✅ Final Checklist

Single tone played.
Basic scale performed.
Happy Birthday melody worked.
Frequency controlled by code.
Personalized melody created.

📚 Extras

🧠 Student tip: Try writing your favorite song with notes and durations.
🧑‍🏫 Instructor tip: Verify buzzer wiring before running.
📖 Glossary: music.MIDI, pitch_time, frequency, duration.
💡 Mini tips: Always test with a single tone before building a melody.