To use voltages above +5vdc you use a limiting resistor, as the C11G can only take +5vdc signals. It is described in the manual. I am not sure what video you are referring to, but you are welcome to open a ticket and we will give you a hand with this: https://www.cnc4pc.com/contact You may want to consider the C94 or C25XP: https://www.cnc4pc.com/c94-multifunction-board-b.html https://www.cnc4pc.com/c25xp-smooth-stepper-integrated-board.html