An electronic device having {TAIL ~ electronic circuitry} powered by a battery and having an interface for interactively coupling the electronic device to a host device, for switching {HEAD ~ the power source} by which power is supplied to the electronic circuitry, and by determining an interface status as being coupled to or detached from the host device 
An electronic device having { TAIL ~ electronic circuitry } powered by a battery and having an interface for interactively coupling the electronic device to a host device , for switching { HEAD ~ the power source } by which power is supplied to the electronic circuitry , and by determining an interface status as being coupled to or detached from the host device
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH