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Of course. But you need to update the software or you need an Arduino variant which supports emulating mouse.
No the ultrasonic sensor is enough. The led and the resistors are used only as indicators.As the toggle switch is used to stop the serial communication from the arduino you can attach to the power supply so that you can cut the power supply to arduino. Or you can attach to a pin of arduino and edit this code a little bit or it can be attached to the wire which power the ultrasound sensor.
How to make a star wars hologram
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