serial/serialPort_loopback-manual.https.html

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<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="resources/common.js"></script>
    <script src="resources/manual.js"></script>
  </head>
  <body>
    <p>
      These tests require a connected serial device configured to act as a
      "loopback" device, with the transmit and receive pins wired together.
    </p>
    <script>
      manual_serial_test(async (t, port) => {
        await port.open({baudRate: 115200, bufferSize: 1024});

        // Create something much smaller than bufferSize above.
        const data = new Uint8Array(64);
        for (let i = 0; i < data.byteLength; ++i)
          data[i] = i & 0xff;

        const reader = port.readable.getReader();

        for (let i = 0; i < 10; ++i) {
          const writer = port.writable.getWriter();
          writer.write(data);
          const writePromise = writer.close();

          const value = await readWithLength(reader, data.byteLength);
          await writePromise;

          compareArrays(value, data);
        }

        reader.releaseLock();
        await port.close();
      }, 'Can perform a series of small writes.');

      manual_serial_test(async (t, port) => {
        await port.open({baudRate: 115200, bufferSize: 1024});

        // Create something much larger than bufferSize above.
        const data = new Uint8Array(10 * 1024);
        for (let i = 0; i < data.byteLength; ++i)
          data[i] = (i / 1024) & 0xff;

        const reader = port.readable.getReader();

        for (let i = 0; i < 10; ++i) {
          const writer = port.writable.getWriter();
          writer.write(data);
          const writePromise = writer.close();

          const value = await readWithLength(reader, data.byteLength);
          await writePromise;

          compareArrays(value, data);
        }

        reader.releaseLock();
        await port.close();
      }, 'Can perform a series of large writes.');

      manual_serial_test(async (t, port) => {
        await port.open({baudRate: 115200, bufferSize: 64});

        const writer = port.writable.getWriter();
        // |data| is small enough to be completely transmitted.
        let data = new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8]);
        await writer.write(data);

        // Wait a little bit for the device to process the incoming data.
        await new Promise((resolve) => setTimeout(resolve, 100));
        // ...before discarding the receive buffers.
        await port.readable.cancel();

        data = new Uint8Array([9, 10, 11, 12, 13, 14, 15, 16]);
        const reader = port.readable.getReader();
        const readPromise = readWithLength(reader, data.byteLength);

        // The next block of data should be received successfully.
        await writer.write(data);
        writer.releaseLock();

        const value = await readPromise;
        reader.releaseLock();

        compareArrays(value, data);

        await port.close();
      }, 'Canceling the reader discards buffered data.');
    </script>
  </body>
</html>