let port = null;

let reader = null;

// serialReceive();

if ("serial" in navigator) {

// The Web Serial API is supported.

console.log("The Web Serial API is supported");

} else {

console.log("The Web Serial API is not supported");

}

async function portSelect() {

port = await navigator.serial.requestPort();

console.log(JSON.stringify(port.getInfo()));

// let ele = document.createElement('option');

// ele.setAttribute("value",JSON.stringify(port.getInfo()));

// ele.setAttribute("selected","selected");

// ele.innerHTML=JSON.stringify(port.getInfo())

// $("#portName")[0].appendChild(ele);

if (port) {

$("#portName").val(JSON.stringify(port.getInfo()));

}

}

//打开串口

async function serialOpen() {

if (port == null) {

alert('打开串口出错');

return;

}

let opt = {

baudRate: 9600,

parity: 0,

dataBits: 8,

stopBits: 1

};

opt.baudRate = parseInt($('#baudRate option:selected').text());

opt.parity = $('#parity option:selected').text();

// switch (tmp) {

// case "none":

// opt.parityMode = 0;

// break;

// case "odd":

// opt.parityMode = 1;

// break;

// case "even":

// opt.parityMode = 2;

// break;

// }

opt.dataBits = parseInt($('#dataBits option:selected').text());

opt.stopBits = parseInt($('#stopBits option:selected').text());

// Wait for the serial port to open.

await port.open(opt);

$("#btnOpen").attr('disabled', 'disabled');

// while (port.readable) {

reader = port.readable.getReader();

try {

while (true) {

const {

value,

done

} = await reader.read();

if (done) {

// Allow the serial port to be closed later.

reader.releaseLock();

break;

}

if (value) {

//value is a Uint8Array.

console.log(value);

const strvalue = new TextDecoder("utf-8").decode(value);

console.log(strvalue);

const temp = $("#receiverText").val();

$("#receiverText").val(temp + strvalue);

}

}

} catch (error) {

// TODO: Handle non-fatal read error.

}

// }

}

//关闭串口

async function serialClose() {

$('#btnOpen').removeAttr('disabled');

try {

await reader.cancel();

await port.close();

} catch (e) {

console.log(e);

//TODO handle the exception

}

}

//串口发送

async function serialSend() {

console.log(document.getElementById("sendText").value.length);

if (document.getElementById("sendText").value.length == 0) {

alert("发送内容不能为空");

return;

}

// console.log(document.getElementById("hexOption").checked);

// hexOption = document.getElementById("hexOption").checked;

const data = $("#sendText").val();

//是否选中16进制

// if (hexOption) {

// const writer = port.writable.getWriter();

// const data = new Uint8Array([104, 101, 108, 108, 111]); // hello

// await writer.write(data);

// // Allow the serial port to be closed later.

// writer.releaseLock();

// } else {

const textEncoder = new TextEncoderStream();

const writableStreamClosed = textEncoder.readable.pipeTo(port.writable);

const writer = textEncoder.writable.getWriter();

await writer.write(data);

// Allow the serial port to be closed later.

writer.releaseLock();

// }

}

//清空接收区

function receiverClear() {

console.log("clear");

document.getElementById("receiverText").value = "";

}