NumberFormat_int8,

        NumberFormat_int16,

        NumberFormat_int32,

        NumberFormat_float,

        NumberFormat_ASCII

    };

    Ui::MainWindow *ui;

    QButtonGroup numberFormatButtons;

    QDialog aboutDialog;

    void setupAboutDialog();

    QSerialPort serialPort;

    unsigned int numOfSamples;

    unsigned int numOfChannels;

    QList<QwtPlotCurve*> curves;

    typedef QVector<double> DataArray;

    DataArray dataX;   // array that simply contains numbers 0..numberOfSamples

    QList<DataArray> channelsData;

    // `data` contains channel specific data

    void addChannelData(unsigned int channel, DataArray data);