Abstract: A dual mode digital video interface for a computer system is disclosed. A video controller generates a video signal to be displayed on the flat panel display. A first interface couples the video controller to the flat panel display in a first display mode when the flat panel display is a first type of display, and a second interface couples the video controller to the flat panel display in a second display mode when the flat panel display is a second type of display. The first interface is enabled when the first type of display is coupled to the computer system, and the second interface is enabled when the second type of display is coupled to the computer system. The dual mode digital video interface may be implemented in a navigation system for a transit vehicle having a computer system for controlling the navigation of the transit vehicle, a global positioning system (GPS) receiver, and a display for displaying positioning and timing information of the transit vehicle received by the GPS receiver.

Abstract: A method for real-time data exchange between an RF modem of a mobile data terminal and a base station host computer of a mobile radio-frequency data communications network is disclosed. In a preferred embodiment, the data exchange timing architecture of the present invention reduces message error rates by accurately predicting signal presence by using a modem hosted by the central processing unit of a mobile data terminal. RF network signal synchronization is improved through precise prediction of the likelihood of message presence, a method that significantly reduces message errors triggered by inadvertent synchronization on signal noise.