Étape 5: Referência
http://Arduino.cc/en/Tutorial/MotorKnobhttp://www.TI.com/lit/DS/symlink/uln2803a.pdf
http://www.stepperworld.com/tutorials/pgBipolarTutorial.htm
http://www.nmbtc.com/PDF/Motors/PM42M048.pdf
http://Arduino.cc/en/Tutorial/StepperBipolar
http://homepage.cs.uiowa.edu/~Jones/Step/example.html
http://www.precisionroller.com/instructions/HP-Designjet-Printhead-Belt-Replacement/
http://www.fixyourownprinter.com/forums/Inkjet/13265