An in-vehicle navigation and information system utilizing defined software services

It is proposed that applications software will be able to be executed properly on entire families of related but dissimilar in-vehicle systems if all software access to the hardware takes place through a defined set of software calls in the ROM BIOS. By allowing map data to be retrieved through a defined high-level retrieval service, application software can be written without requiring detailed familiarity with the data structures, and can be compatible with future map data retrieval services which, while providing the same interface, may provide improved performance. By providing pre-emptive multi-tasking in the vehicular computer environment, application software can be developed efficiently without requiring the developers to take responsibility for the unrelated real-time requirements of navigation, or other software that may also be executed. Unrelated vehicle information systems can use a common compact disk on which multiple versions of executable software are resident.<>