MATLAB BLINK 2 LEDS AT THE SAMETIme

I been trying to blink 2 leds at the same time with different frecuencies, but the pause() function will block matlab and won't let any other code work during that stop time, here is my code

function blinkled4_Callback(hObject, eventdata, handles) % The blind on this led its acitivate by a button nadem blinkled4
% hObject    handle to blinkled4 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
handles.a.configurePin('D4','DigitalOutput');
status1 =get(handles.blinkled4,'string');
    if strcmp(status1,'Turn ON')==1
         set(handles.blinkled4,'string','Turn OFF');
        set(handles.blinkled4,'BackgroundColor','green');
         for i = 1:10
        handles.a.writeDigitalPin('D4', 1);
        pause(0.5);
         handles.a.writeDigitalPin('D4', 0);
        pause(0.5);
         end 
    else
        handles.a.writeDigitalPin('D4',0)
        set(handles.blinkled4,'string','Turn ON');
        set(handles.blinkled4,'BackgroundColor','red');
    
    end

and here is the other code for my other led

    function blinkled5_Callback(hObject, eventdata, handles)
% hObject    handle to blinkled5 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
handles.a.configurePin('D5','DigitalOutput');
status =get(handles.blinkled5,'string');
    if strcmp(status,'Turn ON')==1
         set(handles.blinkled4,'string','Turn OFF');
        set(handles.blinkled4,'BackgroundColor','green');
         for i = 1:10
        handles.a.writeDigitalPin('D5', 1);
        pause(0.5);
         handles.a.writeDigitalPin('D5', 0);
        pause(0.5);
         end 
    else
        handles.a.writeDigitalPin('D5',0)
        set(handles.blinkled4,'string','Turn ON');
        set(handles.blinkled4,'BackgroundColor','red');
    

Any ideas? please help

Answer 1

[Mark Sherstan]

I havent used the MATLAB/Arduino toolbox to much but I modified one of my old Arduino sketches that should help. The key is to use a timer instead of the pause function and check how much time has elapsed and base your on/off from that. Look at my example below and let me know if you have any questions.

% Initialize timer and LED state
previousTime = 0;
ledState = false;

% Start timer 
tic

% Loop for 20 seconds
while toc < 20 
 
  currentTime = toc;

  if (currentTime - previousTime >= 2)
    previousTime = currentTime;
    
    if (ledState == false)
        ledState = true;
    else
        ledState = false;
    end
    
  end
    
   
  % WRITE TO ARDUINO - I think this would work for you assuming it is initialized...
  handles.a.writeDigitalPin('D5', ledState);

end

This isent a direct solution to the functions you posted but you could implment this in your main script and call your sub functions with only a slight modification.

[Vincent Valenzuela]

i have tried implementing your code, but it won't let me blink de 2 leds a the same time, first will blink 1 led, and when its done blinking, then will blink the second led.

[Mark Sherstan]

Here is a more developed script for you, the LED's can be thought of as the output from fprintf being either 1 or 0 / on or off / true or false.

% Initialize timer and LED state
previousTime1 = 0;
previousTime2 = 0;
ledState1 = true;
ledState2 = true;

% Start timer 
tic

% Loop for 10 seconds
while toc < 10 
 
  currentTime = toc;
  
  if (currentTime - previousTime1 >= 1)
    previousTime1 = currentTime;
    
    if (ledState1 == false)
        ledState1 = true;
    else
        ledState1 = false;
    end
    
  end
    
  
  if (currentTime - previousTime2 >= 2)
    previousTime2 = currentTime;
    
    if (ledState2 == false)
        ledState2 = true;
    else
        ledState2 = false;
    end
    
  end  
  
  
  fprintf('%0.0f ',ledState1) 
  fprintf('%0.0f\n',ledState2) 
  
end