Servo Class
===============
This class controls the pen-up and pen-down action of the robot. The class is 
designed for use with a standard hobby servo. It runs PWM at 50 Hz with pulse-widths 
between 80,000 :math:`\mu s` and 120,000 :math:`\mu s` to serve as the 'up' and 'down' 
positions.

.. automodule:: dcDriver
   :members:
   :undoc-members:
   :show-inheritance: