Node Js 通过 serialport 与 Arduino 进行通信
节点 js 代码
开始这个主题的示例是 Node.js 服务器通过 serialport 与 Arduino 进行通信。
npm install express --save
npm install serialport --save
示例 app.js:
const express = require('express');
const app = express();
var SerialPort = require("serialport");
var port = 3000;
var arduinoCOMPort = "COM3";
var arduinoSerialPort = new SerialPort(arduinoCOMPort, {
baudrate: 9600
});
arduinoSerialPort.on('open',function() {
console.log('Serial Port ' + arduinoCOMPort + ' is opened.');
});
app.get('/', function (req, res) {
return res.send('Working');
})
app.get('/:action', function (req, res) {
var action = req.params.action || req.param('action');
if(action == 'led'){
arduinoSerialPort.write("w");
return res.send('Led light is on!');
}
if(action == 'off') {
arduinoSerialPort.write("t");
return res.send("Led light is off!");
}
return res.send('Action: ' + action);
});
app.listen(port, function () {
console.log('Example app listening on port http://0.0.0.0:' + port + '!');
});
启动示例快速服务器:
node app.js
Arduino 代码
// the setup function runs once when you press reset or power the board
void setup() {
// initialize digital pin LED_BUILTIN as an output.
Serial.begin(9600); // Begen listening on port 9600 for serial
pinMode(LED_BUILTIN, OUTPUT);
digitalWrite(LED_BUILTIN, LOW);
}
// the loop function runs over and over again forever
void loop() {
if(Serial.available() > 0) // Read from serial port
{
char ReaderFromNode; // Store current character
ReaderFromNode = (char) Serial.read();
convertToState(ReaderFromNode); // Convert character to state
}
delay(1000);
}
void convertToState(char chr) {
if(chr=='o'){
digitalWrite(LED_BUILTIN, HIGH);
delay(100);
}
if(chr=='f'){
digitalWrite(LED_BUILTIN, LOW);
delay(100);
}
}
启动
- 将 arduino 连接到你的机器。
- 启动服务器
通过节点 js express server 控制 led 的构建。
打开 LED:
http://0.0.0.0:3000/led
要关闭 LED:
http://0.0.0.0:3000/off