from machine import Pin, PWM
import time

# 蜂鸣器引脚
buzzer = PWM(Pin(5))
buzzer.duty(0)  # 初始不响

# 音符频率 (简谱: 1 2 3 4 5 6 7)
NOTE = {
    '1': 262,
    '2': 294,
    '3': 330,
    '4': 349,
    '5': 392,
    '6': 440,
    '7': 494,
    '-': 0  # 休止
}

# 小星星简谱
song = [
    '1','1','5','5','6','6','5',
    '4','4','3','3','2','2','1',
    '5','5','4','4','3','3','2',
    '5','5','4','4','3','3','2',
    '1','1','5','5','6','6','5',
    '4','4','3','3','2','2','1'
]

# 每个音时长（ms）
duration = 300

# 播放函数
def play_tone(note):
    freq = NOTE[note]
    if freq == 0:
        buzzer.duty(0)
    else:
        buzzer.freq(freq)
        buzzer.duty(512)  # 50% 音量

# 播放歌曲
for n in song:
    play_tone(n)
    time.sleep_ms(duration)
    buzzer.duty(0)
    time.sleep_ms(50)

# 结束
buzzer.deinit()