node.js - SerialPort 'close' event never fire -


i'm using nodejs's serialport package connecting computer ports.

about package's close event here.

i have created code, know why close/disconnect event never fire when disconnect com

const express = require('express'); const router = express.router(); // const cors = require('cors'); router.use(cors()); // const serialport = require('serialport'); const readline = serialport.parsers.readline; const port = new serialport('com7',function (err) {     if (err) {         return console.log('error: ', err.message);     } }); const parser = port.pipe(new readline()); /* var lastresult = ''; var count = 0; */  port.on('open', function() {     console.log('~port open.');     parser.on('data', console.log); });  port.on('disconnect', function () {     console.log('disconnected'); }); port.on('close', function () {     console.log('closed'); });  router.get('/', function (req, res) {     res.send('index'); });  module.exports = router;

i'm trying think if use wrong because havn't saw example using event.

thanks :)

i have created timestamp every time recive data com, , check interval() every time.

setinterval(function () {     if (date.now() - lastdatatime > 1000 || !comstatus) {         comstatus = false;         port.close();         port = new serialport(comport, function (err) {             if (err) {                 error = 'error: ' + err.message;                 return console.log(error);             }         });     } }, 1000);

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