.. include:: <mmlalias.txt>


Timers, And Timer Callbacks
===========================

.. topic:: Documentation

   * :doc:`../why-os/timer`

Time Callback
-------------

* On expiry, a specified function is called
* *Caution*: not in schedulable context
* |longrightarrow| **Cannot wait!**

Oneshot Timer
-------------

* Expires once, at *start-time*

.. literalinclude:: code/oneshot.cpp
   :caption: :download:`code/oneshot.cpp`
   :language: c++

Periodic Example
----------------

* Starts at *start-time*, and from then on once every *period*

.. literalinclude:: code/periodic.cpp
   :caption: :download:`code/periodic.cpp`
   :language: c++