I am trying to connect to the serial port from a web page. I found the Serial API which can support that.
var Serial = {};
(function() {
'use strict';
/*
*
*/
Serial.debug = true;
/*
*
*/
// Serial.device;
/*
*
*/
Serial.log = function(message) {
if(Serial.debug)
{
let pre;
if(!document.querySelector('pre'))
{
pre = document.createElement('pre');
document.body.appendChild(pre);
}
pre = document.querySelector('pre');
pre.innerHTML += `\n${message}`;
}
}
/*
*
*/
Serial.request = function() {
const requestOptions = {
// Filter on devices with the Arduino USB vendor ID.
filters: [{ vendorId: 0x0403 }],
};
// Request an Arduino from the user.
console.log(navigator);
console.log(navigator.serial);
const port = navigator.serial.requestPort(requestOptions);
// Open and begin reading.
port.open({ baudrate: 19200 });
const reader = port.in.getReader();
while (true) {
const {done, data} = reader.read();
if (done) break;
console.log(data);
}
}
/*
*
*/
Serial.port = {
/*
*
*/
device:{},
/*
*
*/
connect:function()
{
let loop = () => {
this.device.transferIn(5, 64).then(result => {
Serial.log(result);
loop();
}, error => {
WebUSB.log(error);
});
}
console.log(this.device);
return this.device.open( {baudrate: 19200 })
.then(() => this.device.selectConfiguration(1))
.then(() => this.device.claimInterface(1))
.then(() => this.device.controlTransferOut({requestType: 'class', recipient: 'interface', request: 0x22, value: 0x01, index: 0x02}))
.then(() => {loop})
.then(
result => {
Serial.log('successfull');
}
)
.catch(
error => {
Serial.log(error);
}
);
},
/*
*
*/
send:function()
{
let d = new Date();
let h = d.getHours();
let m = d.getMinutes();
let s = d.getSeconds();
if(h < 10){h = `0${h}`};
if(m < 10){m = `0${m}`};
if(s < 10){s = `0${s}`};
let data = `show time ${h}${s % 2 == 1 ? ':' : ' '}${m}${s % 2 == 0 ? ':' : ' '}${s}`;
console.log(data);
let textEncoder = new TextEncoder();
WebUSB.port.device.transferOut(4, textEncoder.encode(data));
},
/*
*
*/
disconnect:function()
{
console.log(Serial.port.device)
Serial.port.device.close()
.then(
result => {
Serial.log('closed');
document.querySelectorAll('button')[1].parentNode.removeChild(document.querySelectorAll('button')[1]);
}
)
.catch(
error => {
Serial.log(error);
}
);;
}
}
})();
/*
*
*/
window.addEventListener('DOMContentLoaded', connect => {
let button = document.createElement('button');
button.innerHTML = 'Connect a USB Device';
button.addEventListener('click', Serial.request);
document.body.appendChild(button);
}, true);But the navigator.serial.requestPort() call is failing; I find that the navigator.serial is undefined. I'm pretty sure the serial port is connected to my computer. Are functions on navigator.serial and SerialPort in Serial API unimplemented? My chrome version is 74.0.3729.131. My system is Ubuntu 16.04
