It’s a simple premise. After pairing the two devices, a Wii console left in standby mode would communicate with a 3DS console via wireless. If the 3DS leaves range, the Wii would know the user had left; when the machine comes back into wireless range, it’d know the user had returned. The patent explains the TV screen could display a message, or the console could make a sound or illuminate an LED bulb to let people know someone was back. The 3DS too could display a “welcome home” message to its owner.

 

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