how to frequently update an edittext in matlab gui inside a timer function?

Hai guys , As i mentioned i want to update an edittext on matlab gui on each call of the timer function. i am new to matlab and stuck with this issue. i tried something in my way using "set(handles.edit2,'String',sprintf('%d',a(1)));" ,it is working out side the timer function but when i put this inside the timer ,it shows an error . "Error while evaluating TimerFcn for timer 'timer-1'

Not enough input arguments." Please help..

function TmrFcn(src,event,handles)
global s;
fprintf(s,'y');
if(s.BytesAvailable ~= 0)
  a = fscanf(s,'%d,%d,%d,%d,%d,%d');
  a = a';
 Labels = {'LIGHT','METHANE','TEMPERATURE','OXYGEN','H2S','CO'};

    bar(a);
    set(gca, 'XTick', 1:6, 'XTickLabel', Labels);
    handles = guidata(handles);

   set(handles.edit2,'String',sprintf('%d',a(1))); 
    end

Answer 1

[Walter Roberson]

Timer event functions are not automatically passed the handles structure, only the source and event.

When you define your timer callback, instead of saying that the callback is @TmrFcn use a callback of

@(src,event) TmrFcn(src,event,gcf,s)

and define

function TmrFcn(src,event,fignum,s)
  fprintf(s,'y');
  if(s.BytesAvailable ~= 0)
    a = fscanf(s,'%d,%d,%d,%d,%d,%d');
    a = a';
    Labels = {'LIGHT','METHANE','TEMPERATURE','OXYGEN','H2S','CO'};

      bar(a);
      set(gca, 'XTick', 1:6, 'XTickLabel', Labels);
      handles = guidata(fignum);
      set(handles.edit2,'String',sprintf('%d',a(1))); 
    end
  end

[Rijo Kuriakose]

Thank you very much.. it works fine !!