Well, say, we have a photo frame with LEDs around the frame and some elements moving with stepper motors around the frame. There is an IR bumper switch sensing an object came close to the photo frame for some 10cm. I would like to wake up Arduino by this event and only then the whole functionality of the device starts to work.
We can put Arduino in standby mode, ok, but who is then responsible for the IF-THEN-ELSE on the IR sensor, to wake up the Arduino?
Please guide me and if there is any tutorial about this standby concept please point me to it. My knowledge is too much low on this that even googling is hard for the lack of right keywords.