Systems and methods for selectively activating functions provided by a mobile phone

Abstract

Methods for selectively activating one of multiple functions provided by a mobile phone are provided. An embodiment of a method for selectively activating one of multiple functions comprises the following steps. That the mobile phone has been coupled to a computer system is detected. A first interface is displayed to facilitate selection of a first function from the functions. That the first function is selected is detected by the first interface. At least one software module is configured to activate the first function, thereby the computer system is directed to employ the mobile phone as a first external electronic device corresponding to the first function.

1 . A system for selectively activating one of plurality universal serial bus (USB) functions, comprising:
 a USB controller;   a USB connector;   a USB data line connected between the USB controller to the USB connector; and   a regulator disposed between a power source and the USB data line, receiving an enabling signal from the processing unit, and selectively converting the power source to a predetermined voltage level according to the enabling signal, wherein the enabling signal is generated by the processing unit when one of the USB functions is activated;   a connection signal indicating that a USB device has been plugged in is transmitted when converting the power source to the predetermined voltage level, and a disconnection signal indicating that the USB device has been removed is transmitted when not converting the power source to the predetermined voltage level.   
   
   
       2 . The system as claimed in  claim 1  further comprising:
 a switching device disposed between the USB controller and the USB connector, and selectively connecting and disconnecting the data line according to the enabling signal,   the connection signal is transmitted when connecting the data line, and the disconnection signal is transmitted when disconnecting the data line.   
   
   
       3 . The system as claimed in  claim 2  wherein the switching device is a multiplexer or an analog switch. 
   
   
       4 . The system as claimed in  claim 1  wherein the regulator is a power unit embodied in a power management integrated circuit (PMIC). 
   
   
       5 . The system as claimed in  claim 1  wherein the disconnection signal is generated and transmitted by pulling low the USB data line, and the connection signal is generated and transmitted by pulling high the USB data line.