QIODevice::ReadWrite | QIODevice::Unbuffered - Unsupported open mode
<p><a href="http://doc.qt.io/qt-5/qserialport.html#open" rel="nofollow">http://doc.qt.io/qt-5/qserialport.html#open</a></p>

<blockquote>
  <p>Warning: The mode has to be QIODevice::ReadOnly, QIODevice::WriteOnly, or QIODevice::ReadWrite. Other modes are unsupported.</p>
</blockquote>

<p>Following code does not open the serial port.</p>

<pre><code>if(serialPort.open (QIODevice::ReadWrite | QIODevice::Unbuffered))
    {
        qDebug() &lt;&lt; "asdasdas";
        serialPort.setDataBits(QSerialPort::Data8);
        serialPort.setParity(QSerialPort::NoParity);
        serialPort.setStopBits(QSerialPort::OneStop);
    }
    else
    {
        qDebug() &lt;&lt; "QSerialPort::SerialPortError: " &lt;&lt; serialPort.errorString();
    }
</code></pre>

<p><strong>what is the way to use the unbuffered flag?</strong></p>