Nodejs 串口通信： websocket , serialport

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最近在学习如何实现web页面和串口间通信，网页请求使用websocket，实现的基本功能如下：

1、基本需求：硬件：有两个信号灯（TLA-505-1T），一个485继电器（开关），电压转换器，工业触屏一体机。

2、原理图：

3工作原理：

首先一体机中采用node开发服务器，网页请求采用websocket协议，直接放代码了：

var express = require('express');
var SerialPort = require('serialport');
var app = express();
var expressWs = require('express-ws')(app);
var util = require('util');
/*
var com =require('./com.js');
var logger = require('./log.js').logger;
*/


app.use(express.static('public'));
//ejs
app.set('view engine','ejs');app.get('/',function(req,res){res.render('control');
})app.ws('/ws', function(ws, req) {util.inspect(ws);ws.on("message",function(str){console.log('1234');//hander(str,ws);});ws.on("close",function(code,reason){console.log('connection closed');})//处理错误事件信息
    ws.on('error',function(err){console.log('throw err',err);})})
function hander(str,ws) {//发送数据到客户端
    //console.log(str);
    var arr = str.split('');if(arr[2]==1){//close
        arr[2]=0;}else{arr[2]=1;}//console.log(arr.join(''));
    ws.send(arr.join(''));
}app.listen(3004);

这样一个server服务写好，然后在写html界面：

<!DOCTYPE html>
<html lang="en">
<head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="js/jquery.mobile-1.4.5.min.css">
<script src="js/jquery-1.11.3.min.js"></script>
<script src="js/jquery.mobile-1.4.5.min.js"></script><title>Title</title><style>form{margin: 30px auto;width: 35%;}</style></head>
<body>
<br>
<form class="form"><fieldset><legend>websocket 控制</legend><br><br><div>  <button type="button" style="background: #EEF9F3" id="deng1" value="100">灯1关闭状态</button><button type="button" style="background: #EEF9F3" id="deng2" value="110">灯2关闭状态</button></div><br><span id='content'>客户端未连接</span></br><input type="button" value="连接" id="connect" class="connect"/></fieldset>
</form>
<script>var oUl=document.getElementById('content');var oConnect=document.getElementById('connect');var oSend=document.getElementById('send');var oInput=document.getElementById('message');var ws=null;oConnect.onclick=function(){ws = new WebSocket('ws://localhost:3004/ws');ws.onopen=function(){document.getElementById('content').innerHTML = "客户端已连接";}ws.onmessage=function(evt){ //document.getElementById('states').innerHTML = "deng : "+evt.data
            var arr = evt.data.split('');if(arr[1]==0){//deng1
                var deng = "deng1";changeState(deng,'states1');}else if(arr[1]==1){//deng2
                var deng = "deng2";changeState(deng,'states2');} function changeState(deng,state){$('#'+deng).val(evt.data);if(arr[2]==1){//open 
                   // document.getElementById(state).innerHTML = deng+" open:"+evt.data;
                    document.getElementById(deng).innerHTML = (deng =='deng1'?'灯1':'灯2')+"关闭状态";$('#'+deng).css("background-color","#B3B4A6");}else if(arr[2]==0){// document.getElementById(state).innerHTML = deng+" close:"+evt.data;
                    document.getElementById(deng).innerHTML = (deng =='deng1'?'灯1':'灯2')+"打开状态";$('#'+deng).css("background-color","#EEF9F3");}}   }ws.onclose=function(){document.getElementById('content').innerHTML = "客户端已断开连接";};ws.onerror=function(evt){oUl.innerHTML+="<li>"+evt.data+"</li>";};};//$(document).on("pagecreate","#pageone",function(){
      $("#deng1").on("tap",function(){  ws.send($("#deng1").val());});                       
//});
      $("#deng2").on("tap",function(){ ws.send($("#deng2").val());});  /*function clickDend(val){
        console.log(val)
        if(ws){
            ws.send(val);
        }
    }*/
</script>
</body>
</html>

这样一个完整的websocket协议完成，最后在socket协议中加入串口通信：

var express = require('express');
var SerialPort = require('serialport');
var app = express();
var expressWs = require('express-ws')(app);
var util = require('util');
var com =require('./com.js');
/*
var com =require('./com.js');
var logger = require('./log.js').logger;
*/


app.use(express.static('public'));
//ejs
app.set('view engine','ejs');app.get('/',function(req,res){res.render('control');
})app.ws('/ws', function(ws, req) {util.inspect(ws);var sendDelay = 2000;ws.on("message",function(str){console.log('1234');var arr = str.split('');if(arr[2]==1){//close
            arr[2]=0;}else{arr[2]=1;}sendData(arr,ws);//setInterval(sendData,sendDelay);

    });ws.on("close",function(code,reason){console.log('connection closed');})//处理错误事件信息
    ws.on('error',function(err){console.log('throw err',err);})})var defaults = {//reportVersionTimeout: 5000,
    receiveInterval: 100,sendInterval: 500,repeatSendTimes: 30,  // ??????
    SerialName:'/dev/ttyAMA0',SerialPort: {baudRate: 9600,autoOpen: false,parity: 'none',xon: false,xoff: false,xany: false,rtscts: false,hupcl: true,dataBits: 8,stopBits: 1,bufferSize: 11
    }
};var SerialPort = com.SerialPort;
//logger.info('List all serialport');
SerialPort.list(function (err, ports) {ports.forEach(function(port) {console.log(port.comName);console.log(port.pnpId);console.log(port.manufacturer);});
});var test = new com.SerialPort(defaults.SerialName, defaults.SerialPort);var count=0;
var sendTime = Date.now();
test.on('data', function (data) {console.log("receive:"+util.inspect(data));count++;var elapsed = Date.now() - sendTime;console.log("count:"+count+",elapsed:"+elapsed+" ms");
});test.on('error',function (err){console.log("error:"+err);
});test.on('close',function (){console.log("close occured");
});test.open(function (error) {console.log(error);console.log('com port opened');});var cmd1 = Buffer.from([0xaa,0x07,0xde,0x03,0x03,0x01,0x27,0x34,0x10,0x08,0x09]);
var cmd2 = Buffer.from([0xaa,0x07,0xde,0x03,0x03,0x01,0x27,0x34,0x10,0x02,0x03]);
var cmd3 = Buffer.from([0xFE,0x05,0x00,0x00,0xFF,0x00,0x98,0x35]);
var cmd4 = Buffer.from([0xFE,0x05,0x00,0x00,0x00,0x00,0xD9,0xC5]);var cmd5 = Buffer.from([0xFE,0x05,0x00,0x01,0xFF,0x00,0xc9,0xf5]);
var cmd6 = Buffer.from([0xFE,0x05,0x00,0x01,0x00,0x00,0x88,0x05]);var sendCount = 0;
function sendData(arr,ws){console.log("send count:"+arr[1]);if(arr[1]==0){if(arr[2]==0){test.write(cmd3); //灯1 打开
            arr[2]==1;}else if(arr[2]==1){test.write(cmd4);  //灯1 关闭
            arr[2]==0;}}else if(arr[1]==1){if(arr[2]==0){test.write(cmd5); //灯1 打开
            arr[2]==1;}else if(arr[2]==1){test.write(cmd6);  //灯1 关闭
            arr[2]==0;}}ws.send(arr.join(''));
}app.listen(3004);