I want Arduino to control other devices, for example: my HiFi amplifier, my TV, …
This may be in a clean and simple way, the more inocuos way.
1- Add something than can make a button press in the device connecting in parallel, so I can press the button manually and make Arduino “press” the button (but not a noisy relay)
2- Detect lighting leds. In parallel, detect the light, or the current in one led of de device without interfering in its usual function
3- More complex: Interface with some displays to know state of the device, and keeping display running
Please, can anybody give a simple approach? (1 y 2, i know 3 is too complex)