Patent ID: 7654459

Claim:
A method of capturing user control inputs, the method comprising: providing a first navigation member slidably coupled on a housing portion of a portable computer and a stationary second navigation member external to and independent of the portable computer; providing an input card including an optical navigation sensor for detecting relative motion and configuring the input card with a size and a shape for deployment of the input card in a first releasably fixed arrangement relative to the first navigation member and a second movable arrangement relative to the stationary second navigation member; and capturing a first user control input for controlling a function of the portable computer, via communication between the input card and the portable computer, based on relative motion between the optical navigation sensor of the input card and one of respective movable first navigation member and stationary second navigation member, wherein configuring the input card for deployment in the first releasably fixed arrangement comprises: configuring the housing portion to include an input interface comprising the first navigation member and a support portion configured to releasably secure the input card relative to the housing of the portable computer to support the optical navigation sensor in an exposed position relative to first navigation member, and for slidable movement of the first navigation member relative to the support portion; and removably slidably inserting the input card into a slot of support portion of the input interface to detect relative motion between first navigation member and the optical navigation sensor of the input card.