MATLAB Programming Fundamentals - MathWorks

However, in 'error' mode, when the queue is nonempty, the timer calls the function

that you specify using the ErrorFcn property, and then stops processing. The currently

running callback function completes, but the callback in the queue does not execute.

For example, modify mytimer.m (described in the previous section) so that it includes an

error handling function and sets BusyMode to 'error'.

function mytimer()

t = timer;

t.Period = 1;

t.ExecutionMode = 'fixedRate';

t.TimerFcn = @mytimer_cb;

t.ErrorFcn = @myerror;

t.BusyMode = 'error';

t.TasksToExecute = 5;

t.UserData = tic;

start(t)

end

function mytimer_cb(h,~)

timeStart = toc(h.UserData)

pause(1.6);

timeEnd = toc(h.UserData)

end

function myerror(h,~)

disp('Reached the error function')

end

This table describes how the timer manages the execution queue.

Approximate

Elapsed Time

(Seconds)

Action

0 Start the first execution of the callback.

1 Attempt to start the second execution of the callback. The first

execution is not complete, but the execution queue is empty. The

timer adds the callback to the queue.

27 Program Scheduling