print("Hello, ESP32!")
from machine import Pin
import time

# 1. 配置引脚
led = Pin(27, Pin.OUT)                     # LED 引脚设为输出
key = Pin(19, Pin.IN, Pin.PULL_UP)          # 按键引脚设为输入+内部上拉

# 2. 主循环
while True:
    if key.value() == 0:                   # 按下按键 → 引脚被拉低为 0
        led.on()                           # 点亮 LED
    else:                                  # 松开按键 → 引脚恢复高电平 1
        led.off()                          # 熄灭 LED
    time.sleep(0.05)                       # 简易消抖 + 降低 CPU 占用