【メロディーメイカー】紅蓮華

# 概要

子ども向けのプログラミング教育プロジェクトとして、鬼滅の刃第１期OPの紅蓮華をコーディングしてみました。

<iframe width="333" height="592" src="https://www.youtube.com/embed/QWxEfrkcNJI" title="電子工作で紅蓮華" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe>

# ソースコード

```python:main.py
from melody_maker import *

def gurenge():
    """
    紅蓮華
    """
    BPM = 135
    BEAT = 60 / BPM
    melody = [
        [G5, BEAT*4/5],[Gb5, BEAT*4/5],[G5,BEAT*11/5],[REST, BEAT*2/5],
        [G5, BEAT*4/5],[Gb5, BEAT*4/5],[G5,BEAT*11/5],[G4, BEAT/2],
        [G5, BEAT*4/5],[Gb5, BEAT*4/5],[E5, BEAT*8/5],[D5, BEAT/2],[D5, BEAT*2.5],[REST, BEAT/2],

        [B4, BEAT],[D5, BEAT/2],[E5, BEAT*2.5],[REST, BEAT*0.1],
        [E5, BEAT],[G5, BEAT/2],[A5, BEAT*2.5],[REST, BEAT*0.1],
        [G5, BEAT],[A5, BEAT/2],[B5, BEAT*5],[REST, BEAT*0.1],

        [D5, BEAT],[D5, BEAT],[B5, BEAT],
        [A5, BEAT/2],[B5, BEAT/2],[D6, BEAT/2],[B5, BEAT/2],[A5, BEAT/2],[B5, BEAT/4],[B5, BEAT/2],[REST, BEAT/4],
        [G5, BEAT/2],[A5, BEAT/2],[B5, BEAT/2],[D6, BEAT/2],[B5, BEAT/2],[A5, BEAT/2],[B5, BEAT/4],[B5, BEAT/2],[REST, BEAT/4],
        [D5, BEAT/2],[D5, BEAT/2],[G5, BEAT/4],[G5, BEAT*3/4],[D5, BEAT/2],[D5, BEAT/2],[G5, BEAT/2],[A5, BEAT/2],[G5, BEAT/2],
        [D6, BEAT],[C6, BEAT],[B5, BEAT*3/4],[A5, BEAT*3/4],[G5, BEAT/2],[G5, BEAT*5/4],[REST, BEAT/4],
        [G5, BEAT],[A5, BEAT/2],[B5, BEAT/2],[A5, BEAT*5/4],[REST, BEAT/4],
        [D5, BEAT/2],[A5, BEAT],[B5, BEAT/2],[D6, BEAT/2],[A5, BEAT/2],[B5, BEAT*4],[REST, BEAT],
    ]
    for m in melody:
        tone(m[0], m[1])


while True:
    turn_on_led(color)
    if button_red.value() == 1:
        gurenge()
    elif button_green.value() == 1:
        pass
    elif button_blue.value() == 1:
        pass
    elif button_yellow.value() == 1:
        pass
    elif button_orange.value() == 1:
        pass
    sleep(0.1)
    turn_off_led(color)
    if color < 4:
        color += 1
    else:
        color = 0

```

```python:melody_maker.py
from machine import Pin, PWM
from utime import sleep

# LED
led_red = Pin(0, Pin.OUT, value=1)
led_green = Pin(2, Pin.OUT, value=1)
led_blue = Pin(3, Pin.OUT, value=1)
led_yellow = Pin(9, Pin.OUT, value=1)
led_white = Pin(10, Pin.OUT, value=1)

# NPNトランジスタのベース
buzzer = PWM(Pin(15))

# ボタン
button_red = Pin(1, Pin.IN, Pin.PULL_DOWN)
button_green = Pin(11, Pin.IN, Pin.PULL_DOWN)
button_blue = Pin(12, Pin.IN, Pin.PULL_DOWN)
button_yellow= Pin(13, Pin.IN, Pin.PULL_DOWN)
button_orange = Pin(14, Pin.IN, Pin.PULL_DOWN)


# 音の周波数
REST=    0
C4  =  262
Db4 =  277
D4  =  294
Eb4 =  311
E4  =  330
F4  =  349
Gb4 =  370
G4  =  392
Ab4 =  415
A4  =  440
Bb4 =  466
B4  =  494
C5  =  523
Db5 =  554
D5  =  587
Eb5 =  622
E5  =  659
F5  =  698
Gb5 =  740
G5  =  784
Ab5 =  831
A5  =  880
Bb5 =  932
B5  =  988
C6  = 1047
Db6 = 1109
D6  = 1175
Eb6 = 1245
E6  = 1319
F6  = 1397
Gb6 = 1480
G6  = 1568
Ab6 = 1661
A6  = 1760

# 光っているLEDを管理する変数
color = 0

def turn_on_led(color):
    """
    指定したLEDを点灯する。

    Parameters:
        color(int):
            0: 赤
            1: 緑
            2: 青
            3: 黄色
            4: 白
    """
    if color == 0:
        led_red.value(0)
    elif color == 1:
        led_green.value(0)
    elif color == 2:
        led_blue.value(0)
    elif color == 3:
        led_yellow.value(0)
    elif color == 4:
        led_white.value(0)
        
def turn_off_led(color):
    """
    指定したLEDを消灯する。
    
    Parameters:
        color(int):
            0: 赤
            1: 緑
            2: 青
            3: 黄色
            4: 白
    """
    if color == 0:
        led_red.value(1)
    elif color == 1:
        led_green.value(1)
    elif color == 2:
        led_blue.value(1)
    elif color == 3:
        led_yellow.value(1)
    elif color == 4:
        led_white.value(1)

def tone(frequency, duration):
    """
    パッシブブザーで音を鳴らす。

    Parameters:
        frequency(int): 周波数
        duration(float): 音の長さ
    """
    global color
    if frequency == REST:
        turn_on_led(0)
        turn_on_led(1)
        turn_on_led(2)
        turn_on_led(3)
        turn_on_led(4)
        sleep(duration)
        turn_off_led(0)
        turn_off_led(1)
        turn_off_led(2)
        turn_off_led(3)
        turn_off_led(4)
        return
    turn_on_led(color)
    buzzer.freq(frequency)
    buzzer.duty_u16(30000)
    sleep(duration)
    buzzer.duty_u16(0)
    sleep(0.002)
    turn_off_led(color)
    if color < 4:
        color += 1
    else:
        color = 0

```

# メロディーメイカーの作り方

動画で作り方を解説しています。

https://youtu.be/d7pTfG6R1M8