Function to stop the running serial communication of comport

Hello,

The serial communication using comport is working fine and the main lines of code are

s1 = open_com_port(com_port);   
        gui_update_freq_divisor = 20;
        flushBytesThreshold = 500;
        k = 1; 
 pulse_count=0;period(20)=0;results(100)=0;max1=0;
        while ~s_quitgui           
            nb = s1.BytesAvailable;
            if nb > flushBytesThreshold
                   error('serial data overflow')
            end            
            if(nb) 
                currtime(k) = sampleCounter*dt;
                [tline,count] = fgetl(s1);
                data_tmp = str2num(char(tline));
                  data(k)=(data_tmp);              
                if s_writetofile
                    fprintf(FID,'%f %f \n',currtime,data);
                end
                % update gui not so often
                if (~mod(sampleCounter,gui_update_freq_divisor)) 
                    for i=1:1:20
                        if (data(i)==4095)                              
                            results(i)=1;
                        else
                            results(i)=0; 
                        end
                    end    
                        max1=max(results);                                      
                    axes(rawax_gyr)
                    set(raw1_gyr,'XData',[get(raw1_gyr,'Xdata') currtime]);
                    set(raw1_gyr,'YData',[get(raw1_gyr,'YData') data]);                           
                    % Slide x-axis of the smaller axes
                    set(rawax_gyr,'XLim',[currtime(1)-10 currtime(1)])    
                    set(rawax_gyr,'YLim',[-10 5000])  
                      k = 0;i=1;
                      %drawnow
                  end               
                  sampleCounter = sampleCounter + 1;
                  k = k + 1;
              end
              %pause(0.0001);
          end       
          delete(s1)
          close(fh)
end

But what are the lines(command) needed to stop the serial communication of COMPORT.

I am planning to implement this a GUI and for start button the serial communication starts but can I know what are the needed lines in the pushbutton call back fucntion so that it stops the communication when stop button is pressed .

[Walter Roberson]

Please explain the difference between this question and your earlier http://www.mathworks.co.uk/matlabcentral/answers/121610-adding-stop-button-to-stop-the-data-streaming-from-comport-to-gui-builder

[Gova ReDDy]

Both were asked for the same purpose but for the first one I got more information to solve and improve the GUI working.

So, I want to go(solve) step by step as per the above suggestions and in this process I want to add the pushbutton(stop)function but I don't know how to make this(stopping the communication of comport).

Can you please explain a function(method) to stop the communication when a stop is pressed on the GUI.

[Walter Roberson]

Undefined function or variable s_quitgui

[Gova ReDDy]

I tired to stop the communication using delete(open_com_port(12)) in the stopbutton function but it is stopping the data streaming

function varargout = start1(varargin)
  gui_Singleton = 1;
  gui_State = struct('gui_Name',       mfilename, ...
                     'gui_Singleton',  gui_Singleton, ...
                     'gui_OpeningFcn', @start1_OpeningFcn, ...
                     'gui_OutputFcn',  @start1_OutputFcn, ...
                     'gui_LayoutFcn',  [] , ...
                     'gui_Callback',   []);
  if nargin && ischar(varargin{1})
      gui_State.gui_Callback = str2func(varargin{1});
  end

    if nargout
        [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
    else
        gui_mainfcn(gui_State, varargin{:});
    end

    function start1_OpeningFcn(hObject, eventdata, handles, varargin)
    handles.output = hObject;
    guidata(hObject, handles);

    function varargout = start1_OutputFcn(hObject, eventdata, handles) 
    varargout{1} = handles.output;

    start=uicontrol('Style','pushbutton','String', 'start', 'Position',[20 400 50 20],'Callback',@startbutton_Callback);
    stop=uicontrol('Style','pushbutton','String', 'stop', 'Position',[100 400 50 20],'Callback',@stopbutton_Callback);
    Exit=uicontrol('Style','pushbutton','String', 'Exit', 'Position',[20 20 50 20],'Callback',@Exitbutton1_Callback);

    function Exitbutton1_Callback(hObject, eventdata)
    handles = guidata(hObject);
     s_quitgui = true;
    display('Goodbye');
    close(gcf);

    function startbutton_Callback(hObject, eventdata)
    handles = guidata(hObject);
    axes(handles.axes2);
    linewidth = 1; 
    raw1_gyr = line('Parent',handles.axes2,...
        'XData',[],...
        'YData',[],...
        'Color',[0 0 1],...
        'LineWidth',linewidth);
    com_port = 12;
    sampleCounter = 1;
    dt =  5*(1e-2);
    data_file_name = 'idm30_data.txt';
    FID = [];
    s_writetofile = false;
    s_quitgui = false;
    s1 = open_com_port(12);
    gui_update_freq_divisor = 20;
    flushBytesThreshold = 1000;
    k = 1;
        while ~s_quitgui            
                nb = s1.BytesAvailable;            
                if nb > flushBytesThreshold
                    error('serial data overflow')
                end            
                if(nb)                
                    currtime(k) = sampleCounter*dt;                
                    [tline,count] = fgetl(s1);
                    data_tmp = str2num(char(tline));
                    data(k)=(data_tmp);

                    if s_writetofile
                        fprintf(FID,'%f %f \n',currtime,data);
                    end

                    if (~mod(sampleCounter,gui_update_freq_divisor))                   
                        axes(handles.axes2);
                        set(raw1_gyr,'XData',[get(raw1_gyr,'Xdata') currtime]);
                        set(raw1_gyr,'YData',[get(raw1_gyr,'YData') data]);
                        set(handles.axes2,'XLim',[currtime(1)-1 currtime(1)])
                        set(handles.axes2,'YLim',[-1 5000])                    
                        k = 0;
                    end                
                    sampleCounter = sampleCounter + 1;
                    k = k + 1;
                end
            end        

    function stopbutton_Callback(hObject, eventdata)
    handles = guidata(hObject);
     delete(open_com_port(12))

    function textbox1_Callback(hObject, eventdata, handles)

    function textbox1_CreateFcn(hObject, eventdata, handles)
    if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
        set(hObject,'BackgroundColor','white');
    end

Can someone explain the way to stop the serial data streaming of comport.

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_share_data_between_callback_functions_in_my_GUI.3F

[Gova ReDDy]

Thanks for the information,this will help me in improving the GUI but I really didn't get how to stop the serial communication.

I improved the GUI a bit more but got the problem mentioned here . Can you please help me out in solving this issue.

[Walter Roberson]

You are trying to set a quit flag in one routine and you are trying to read the quit flag in another routine. The FAQ talks about how to share information between routines.

See also http://www.mathworks.co.uk/matlabcentral/answers/100558-how-do-i-set-up-a-uicontrol-callback-to-interrupt-a-routine