Java物联网硬件开发教程：实现智能交通信号灯控制功能

int redPin = 2; // 红灯引脚
int yellowPin = 3; // 黄灯引脚
int greenPin = 4; // 绿灯引脚

void setup() {
  pinMode(redPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
}

void loop() {
  // 设置红灯亮，黄灯熄灭，绿灯熄灭
  digitalWrite(redPin, HIGH);
  digitalWrite(yellowPin, LOW);
  digitalWrite(greenPin, LOW);
  delay(5000); // 等待5秒

  // 设置红灯熄灭，黄灯亮，绿灯熄灭
  digitalWrite(redPin, LOW);
  digitalWrite(yellowPin, HIGH);
  digitalWrite(greenPin, LOW);
  delay(2000); // 等待2秒

  // 设置红灯熄灭，黄灯熄灭，绿灯亮
  digitalWrite(redPin, LOW);
  digitalWrite(yellowPin, LOW);
  digitalWrite(greenPin, HIGH);
  delay(5000); // 等待5秒
}

import java.io.OutputStream;
import gnu.io.CommPortIdentifier;
import gnu.io.SerialPort;

public class TrafficLightController {
    private static final String PORT_NAME = "COM3"; // 将COM3替换为你的串口号
    private static final int BAUD_RATE = 9600; // 设置波特率

    public static void main(String[] args) {
        try {
            CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(PORT_NAME);
            SerialPort serialPort = (SerialPort) portIdentifier.open("TrafficLightController", 2000);
            serialPort.setSerialPortParams(BAUD_RATE, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);

            OutputStream outputStream = serialPort.getOutputStream();

            while (true) {
                // 设置红灯亮，黄灯熄灭，绿灯熄灭
                outputStream.write("red".getBytes());
                Thread.sleep(5000); // 等待5秒

                // 设置红灯熄灭，黄灯亮，绿灯熄灭
                outputStream.write("yellow".getBytes());
                Thread.sleep(2000); // 等待2秒

                // 设置红灯熄灭，黄灯熄灭，绿灯亮
                outputStream.write("green".getBytes());
                Thread.sleep(5000); // 等待5秒
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}