arduino的红绿灯倒计时代码

Arduino是一种开源电子平台，常用于制作基于数字IO控制硬件的项目。如果你想要编写一个简单的红绿灯倒计时程序，通常会涉及到使用Timer库来定时切换LED灯的颜色。下面是一个基本的示例，假设你有三个LED连接到数字端口：

#include <TimerOne.h>

// LED pin connections (replace with your own)
const int led_red = 9;
const int led_green = 10;
const int led_yellow = 11;

TimerOne timer; // Timer object for the delay

void setup() {
  pinMode(led_red, OUTPUT);
  pinMode(led_green, OUTPUT);
  pinMode(led_yellow, OUTPUT);

  Serial.begin(9600); // Enable serial communication for debugging
}

void loop() {
  // Set initial time (seconds) for each color cycle
  int red_time = 5;
  int green_time = 3;
  int yellow_time = 2;

  // Start a loop that alternates colors
  while (true) {
    if (!timer.isExpired(red_time * 1000)) { // Check if red light time has expired
      digitalWrite(led_red, HIGH); // Turn on red
      digitalWrite(led_green, LOW);
      digitalWrite(led_yellow, LOW);
    } else {
      timer.restart(); // Reset the timer for red

      if (!timer.isExpired(green_time * 1000)) { // Check if green time has expired
        digitalWrite(led_red, LOW);
        digitalWrite(led_green, HIGH); // Turn on green
        digitalWrite(led_yellow, LOW);
      } else {
        timer.restart(); // Reset the timer for green

        if (!timer.isExpired(yellow_time * 1000)) { // Check if yellow time has expired
          digitalWrite(led_red, LOW);
          digitalWrite(led_green, LOW);
          digitalWrite(led_yellow, HIGH); // Turn on yellow
        } else {
          // Repeat the cycle or start over here
        }
      }
    }
  }
}