| 摘要 |
PURPOSE:To update existent map data by adding road data on a part whose actual road state is different from a displayed map to the existent road data when the actual road state is different from the displayed map. CONSTITUTION:A road memory 8 is connected additionally to a position detection unit 5. When a driver wants to write a road not shown in the existent map data, read out of a CD-ROM 9, in a map, a road memory switch on an operation device 3 is pressed to write the road in the road memory 8, which can be accessed as a new map from the operation device 3 as well as the map data in the CD-ROM 9. When the driver travels on a new road which is not shown in the map data during a drive while the existent map data is displayed, the travel trace of the new road is displayed distinctively in different form travel traces of other roads on a display device 2. Data on the new road is stored in the additionally provided road memory 8 when necessary and when the driver travels at the same place next time, the new road data stored in the road memory 8 is displayed as well as the existent map data. |
