====== 串口 ======
----

https://blog.csdn.net/u012612399/article/details/80421730

安装serialport

npm install serialport



串口代码
<code javascript>
var SerialPort = require('serialport')
//Opening a Port
var serialPort = new SerialPort('COM3', {
    baudRate : 115200,
    autoOpen:false
})

serialPort.open(function (err) {
    console.log('IsOpen:',serialPort.isOpen)
    console.log('err:',err)
    if(!err){
        const buf1 = new Buffer("01050000ff008C3A","hex") //打开红灯
        const buf11 = new Buffer("010500000000CDCA","hex") //关闭红灯
        const buf2 = new Buffer("01050001f000D80A","hex") //打开黄灯
        const buf21 = new Buffer("0105000100009C0A","hex") //关闭黄灯
        const buf3 = new Buffer("01050002f000280A","hex") //打开绿灯
        const buf31 = new Buffer("0105000200006C0A","hex") //关闭绿灯
        const bufs = [buf1,buf2,buf3]

        var i = 0
        eachWrite(bufs[i])
        function eachWrite(item) {
            console.log(item)
            serialPort.write(item, function (error, result) {
                i++
                if(i>=bufs.length)return

                setTimeout(function () {
                    eachWrite(bufs[i])
                },40)
            })
        }
    }
})

serialPort.on('data',function (data) {
    console.log('data received: '+data)
})

serialPort.on('error',function (error) {
    console.log('error: '+error)
})


SerialPort.list(function (error, ports) {
    ports.forEach(function(port) {
        console.log(port.comName);
        console.log(port.pnpId);
        console.log(port.manufacturer);
    });
})
</code>