Portable computer system having and a method for an audio expansion control function

A computer system including a portable computer and a docking station, comprising:

• said portable computer comprising:
• a sound source for generating a digital audio signal output;
• a host audio chip for receiving said digital audio signal output of said sound source and for converting said digital audio signal output into an analog audio output;
• a host audio amplifier for amplifying said analog audio output of said host audio chip;
• a host speaker connected to an output of said host audio amplifier and providing an audible sound output corresponding to said analog audio output of said host audio chip;
• an audio controller and an amplifier switch connected to said host audio amplifier for selectively turning said host audio amplifier on and off in accordance with a station sense signal input to said audio controller so that said analog audio output from said host audio chip in said portable computer is then only amplified by an audio amplifier in said docking station;
• and
• a host docking connector for receiving said station sense signal from said docking station and for providing said analog audio output from said host audio chip to said docking station;
• and
• said docking station comprising:
• a docking station docking connector operationally connecting said docking station to said host docking connector, for transmitting said station sense signal to said portable computer and for receiving from said portable computer said analog audio output of said host audio chip;
• a station audio amplifier for providing said station sense signal to said docking station docking connector and for receiving and amplifying said analog audio output of said host audio chip;
• and
• a station speaker connected to an output of said station audio amplifier and providing an audible sound output corresponding to said analog audio output of said host audio chip.

A method of operating an audio expansion system for a portable computer, the method comprising the steps of:

• mating a portable computer having an audio processing circuit including an audio chip and having an internal speaker with a docking station having an extra speaker;
• driving selectively a first audio amplifier disposed in said portable computer to amplify an audio output signal fed from said audio chip in said portable computer;
• driving a second audio amplifier disposed in said docking station to amplify said audio output signal fed from said audio chip in said portable computer;
• and
• providing a controller for selectively disabling said first audio amplifier in response to a signal fed from said docking station so that said audio output signal is fed from said audio chip in said portable computer to said second audio amplifier and is then only amplified by said second audio amplifier.