I am working on a project. I want to write 0xFF through the USB port to another circuit, which has a current amplifier. Is it possible to do this with an Android phone?
Secondly, how does the battery sensor work in an Android phone, to be more clear, when the phone is plugged in - the phone's LED turns RED and when the battery is completely charged the RED light turns GREEN. How is that possible, is it achieved via a hardware within or a software?