assets/js/serialUtil.js


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43

function delay(ms) {
    return new Promise(resolve => setTimeout(resolve, ms));
}

async function openPortLineBreak(port, baudRate, outputErrorCallback) {
    try {
        await port.open({ baudRate: baudRate });
    } catch (err) {
        outputErrorCallback(`Error: ${err.message}`);
        return;
    }

    const textDecoder = new TextDecoderStream();
    const readableStreamClosed = port.readable.pipeTo(textDecoder.writable);
    const reader = await textDecoder.readable.pipeThrough(new TransformStream(new LineBreakTransformer())).getReader();
    const textEncoderStream = new TextEncoderStream();
    const writerStreamClosed = textEncoderStream.readable.pipeTo(port.writable);
    const writer = await textEncoderStream.writable.getWriter();

    return { reader, writer, readableStreamClosed, writerStreamClosed };
}

async function closePortLineBreak(port, reader, writer, readableStreamClosed, writerStreamClosed) {
    if (reader) {
        reader.cancel();
    }

    if (readableStreamClosed) {
        await readableStreamClosed.catch(() => { /* Ignore the error */ });
    }

    if (writer) {
        writer.close();
    }

    if (writerStreamClosed) {
        await writerStreamClosed;
    }

    if (port) {
        await port.close();
    }
}