Arduino enthusiast Didier Longueville has created a simple electric motor using only an Arduino and some simple wiring, without using a motor shield or driving transistors. Although his motor is for demonstration purposes, Dider uses an interesting method of maximising the amount of current one can source from an Arduino by using multiple digital outputs almost simultaneously and port manipulation. If you're going to repeat this or modify it for your own use, be mindful of the current draw on each pin.
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