Arduino 中led灯加按键加数字显示器加蜂鸣器的代码和电路图

在Arduino中，连接LED灯、按键、数字显示器（通常是7段数码管）和蜂鸣器的基本电路和代码如下：

**电路图概要：**
1. LED灯接到数字输出引脚，通常是通过电阻降压。
2. 按键连接到数字输入引脚，可以使用中断检测按下的动作。
3. 数字显示器（74HC595接口）需要数据线、时钟线和使能线连接到Arduino的I/O线上。
4. 蜂鸣器一般通过模拟输出引脚控制其占空比。

**简单代码示例：**

#include <Wire.h> // For I2C communication with the 7-segment display
#include <LiquidCrystal_I2C.h>
#include <Adafruit_DHT.h>

// Define pins for components
const int ledPin = 9; // LED connected to digital pin 9
const int buttonPin = 2; // Button connected to digital pin 2
const int digitSelect = 10; // Display select pin
const int clockPin = 11; // Display clock pin
const int dataPin = 12; // Display data pin
const int buzzerPin = 3; // Buzzer connected to analog pin 3

LiquidCrystal_I2C lcd(0x27, 16, 2); // Assuming a common I2C address and 16-digit display

void setup() {
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(digitSelect, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(dataPin, OUTPUT);
  digitalWrite(digitSelect, LOW); // Initialize the display in common cathode mode
  attachInterrupt(digitalPinToInterrupt(buttonPin), buttonPressed, FALLING); // Interrupt on falling edge
  DHT.begin(11, 4); // DHT sensor connected to pin 4 (DHT11 or similar)
}

void loop() {
  float humidity, temperature;
  bool isButtonPressed;

  if (DHT.readingAvailable()) {
    humidity = DHT.humidity();
    temperature = DHT.temperature();
    lcd.setCursor(0, 0);
    lcd.print("Temp: ");
    lcd.print(temperature);
    lcd.print("°C");
    lcd.setCursor(0, 1);
    lcd.print("Humidity: ");
    lcd.print(humidity);
    lcd.print("%");
  }

  isButtonPressed = digitalRead(buttonPin) == LOW; // Check if button is pressed
  if (isButtonPressed) {
    digitalWrite(ledPin, HIGH); // Turn on LED
    tone(buzzerPin, 500, 200); // Play short beep
  } else {
    digitalWrite(ledPin, LOW); // Turn off LED
    noTone(buzzerPin); // Stop beeping
  }
}

void buttonPressed() {
  // Your code here when button is released, e.g., update the display or do something else
}

这个代码片段设置了基本的传感器读取、LCD显示当前温度和湿度，并响应按键操作。当按键按下时，LED亮起并发出短促的声音；松开按键后，LED关闭并且停止发声。

**