MIDI-TO-ARDUINO-CONVERTER

A Python script by Vihanga Nethmaka that converts single-track MIDI files into ready-to-use C/C++ arrays (melody_data.h) for playing music on microcontrollers like Arduino Uno and ESP32 using the tone() function.

1. How to Use the Converter (app.py)

Unlike command-line converters, this script uses a simple configuration variable, making the workflow extremely straightforward.

Prerequisites (Software)

1. Python: Ensure you have Python 3.x installed.

2. Mido Library: You need the mido library to read and parse MIDI files. Install it using pip:

pip install mido

Conversion Steps

1. Select MIDI File: Place your desired single-track MIDI file (e.g., my_new_song.mid) into the same root directory as the app.py script.

2. Edit app.py: Open the app.py file and locate the configuration section near the top. You must change the MIDI_FILENAME variable to the exact name of your MIDI file (the currently selected line in your Canvas):

# Example Change:

MIDI_FILENAME = "my_new_song.mid"

3. Run the Script: Execute the Python file from your terminal:

python app.py

4. Find the Output: The script will automatically create a folder named MIDI_Tune_Player (if it doesn't exist) and place the generated code in:

MIDI_Tune_Player/melody_data.h

(Note: If a melody_data.h file already exists, the script will automatically back it up to the MIDI_Tune_Player/Backups folder before generating the new one.)

2. Circuit Setup for Buzzer Playback

This project uses a simple passive piezoelectric buzzer. The connection is straightforward, but adding a resistor is recommended for component protection.

Components Needed

• Arduino Uno or ESP32 Development Board

• Passive Piezoelectric Buzzer

• Jumper Wires

• Current-Limiting Resistor ($\approx 220 \text{ Ω}$ recommended)

Wiring Instructions and Microcontroller Specifics

Safety Note: Using a current-limiting resistor (like $\mathbf{220 \text{ Ω}}$ or similar, such as $\mathbf{100 \text{ Ω}}$ to $\mathbf{330 \text{ Ω}}$) in series with the positive lead of the passive piezo buzzer is a best practice for protecting the microcontroller's digital pin from back EMF.

Part A: Arduino Uno Circuit

The Arduino Uno uses the standard tone() function.

Arduino Uno Wiring

1. Connect one end of the Resistor to Digital Pin 8 on the Arduino Uno.

2. Connect the other end of the Resistor to the Positive (+) lead of the Passive Buzzer.

3. Connect the Negative (-) lead of the Passive Buzzer to a GND pin on the Arduino Uno.

Storage Warning (Arduino Uno)

The Arduino Uno has limited Flash memory (typically $32 \text{ KB}$). Since the converted music data arrays are stored using the PROGMEM keyword (Flash memory), long songs can easily consume all available storage.

• Be aware that a melody with several hundred notes might exceed the memory limit of the Uno. Consider using shorter MIDI files or upgrading to a board with more flash memory (like an ESP32 or Arduino Mega) for complex pieces.

Part B: ESP32 Circuit

The ESP32 uses the powerful LED Control (LEDC) peripheral for high-precision tone generation, which is handled automatically by the standard Arduino tone() function used in the sketch.

ESP32 Wiring

1. Connect one end of the Resistor to GPIO Pin 25 on the ESP32 Development Board.

2. Connect the other end of the Resistor to the Positive (+) lead of the Passive Buzzer.

3. Connect the Negative (-) lead of the Passive Buzzer to a GND pin on the ESP32.

Wiring Diagrams Summary

Board	Connection Details	Digital Pin Constant
Arduino Uno	Buzzer (via Resistor) to Digital Pin 8 and GND.	const int BUZZZER_PIN = 8;
ESP32	Buzzer (via Resistor) to GPIO Pin 25 and GND.	const int BUZZZER_PIN = 25;

3. Example Files and Copyright Information

This repository may contain MIDI files and corresponding converted arrays for demonstration purposes.

• Example 1 (Provided as MIDI): IRIS OUT (Chainsaw Man - The Movie: Reze Arc Opening)

• Source: https://www.midishow.com/en/midi/download?id=229556

• Example 2 (Provided as C Array): Darling in the FRANXX - Kiss of death

• Source: Original MIDI obtained from https://www.hamienet.com/midi49214_Darling-in-the-FRANXX-Kiss-of-death.html

Important Copyright Notice: The MIDI files used in this project are based on copyrighted original musical compositions. These examples are provided solely for educational and personal use to demonstrate the functionality of the Python script. If you intend to use any generated musical data for public performance, distribution, or commercial purposes, you are responsible for obtaining the necessary licenses and permissions from the original copyright holders.

4. Licensing and Attribution

Author & Contributor

This project was created and is maintained by:

Vihanga Nethmaka

• GitHub: https://github.com/VihangaNethmaka

License MIT