function varargout = update_gui(varargin)

persistent plot_handle1

rto2 = get_param('Beispiel4_sim/Out1','RuntimeObject');

XData1 = get_param('Beispiel4_sim','SimulationTime');
YData1 = rto2.InputPort(1).Data;

% real-time plot

if isempty(plot_handle1) || ~ishandle(plot_handle1)
    guiplot1=findobj(0, 'Tag','axesplot1');
    plot_handle1 = plot(guiplot1, XData1, YData1);
else
    XData_old1 = get(plot_handle1, 'XData');
    YData_old1 = get(plot_handle1, 'YData');
    XData1 = [XData_old1, XData1];
    YData1 = [YData_old1, YData1];
    set(plot_handle1, 'XData', XData1)
    set(plot_handle1, 'YData', YData1)
    %axis([0 20 0 10])
    drawnow
end