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* Arduino PID Library - Version 1.2.1

* by Brett Beauregard <br3ttb@gmail.com> brettbeauregard.com

*

* This Library is licensed under the MIT License

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- For an ultra-detailed explanation of why the code is the way it is, please visit:

http://brettbeauregard.com/blog/2011/04/improving-the-beginners-pid-introduction/

- For function documentation see: http://playground.arduino.cc/Code/PIDLibrary