Patent ID: 6725318
Filing Date: 2004-04-20
Classification: G06F

Abstract:
An external user input device adapted to selectively couple and communicate user input data through at least one of a universal serial bus (USB) port and an alternative port of a host computing device, comprising:(a) at least one data switch capable of being activated by a user to determine data that are transmitted to a host computing device; (b) a power sense circuit that determines whether electrical power is being supplied to the external user input device from an alternative port of a host computing device and produces a signal indicative thereof; and (c) a state switch, coupled to the power sense circuit and said at least one data switch, to receive the signal produced thereby, and in response upon detecting a change in state to said signal indicating that an alternative port is supplying the electrical power indicative thereof, enabling the host computing device to receive data transmitted from said at least one data switch through an alternative port, and otherwise enabling the host computing device to receive data transmitted from said at least one data switch through a USB port.