How can I output a series of pulses using the Data Acquisition Toolbox?

I want to output a series of digital pulses using the Data Acquisition Toolbox in MATLAB. I would like the pulses to have a period of 7 miliseconds: "off" for 5 miliseconds and "on" for 2 miliseconds.

Answer 1

[MathWorks Support Team]

This can be done using the following code:

function sendPulse(numofperiods, ontime, offtime)

      % creates a digital I/O object

      parport = digitalio('parallel','LPT1');

      % adds out line to the digital I/O object

      hwline = addline(parport,0,'out');

      %configures the digital I/O object

      set(parport, 'TimerPeriod', offtime);

      set(parport, 'TimerFcn', {@puton, numofperiods, ontime, offtime});

      set(parport, 'UserData', 0);

      putvalue(parport.Line(1), 0); %pulse is off

      start(parport);

end

% Subfunction that switches the pulse "on" or "off"

% and also stops the object when the specified

% number of periods has been reached.

function puton(obj, str, numofperiods, ontime, offtime)

      obj.TimerFcn = {@putoff, numofperiods, ontime, offtime};

      obj.TimerPeriod = offtime;

      putvalue(obj.Line(1), 1); %pulse is on

      if (obj.UserData == numofperiods)

          obj.TimerFcn = ' ';

          stop(obj);

      end

      obj.UserData = obj.UserData +1

end

function putoff(obj, str, numofperiods, ontime, offtime)

      obj.TimerFcn = {@puton, numofperiods, ontime, offtime};

      obj.TimerPeriod = ontime;

      putvalue(obj.Line(1), 0); %pulse is off

end

To call the the function, run the following command:

% outputs 10 periods of a pulse that's 

% "off" for 5 ms and "on" for 2 ms

sendPulse(10,.002,.005)