| 摘要 |
PURPOSE:To automatically present a map in a suitable range according to the travelled distance by a method wherein the map and the relation among this and other maps are stored in a memory so as to display the map involved from the data on the starting point, the main travel route and the actual distance being covered. CONSTITUTION:A time zone and a frequency during which traffic information is given have been set in a memory 1 beforehand. A processing unit 5 is so arranged that it causes a receiver 8 to be ready for receiving in tune with the corresponding frequency in the preset time zone. When the receiver 8 receives traffic information in the preset time zone in this state, it extracts the information following the key word from the traffic information and converts the information into a code corresponding to a local name within the memory 1 and the write the converted code, the time stored and the information extracted to an update data memory 9. When a map is displayed in a display unit 6 in this state, update traffic information is produced by an audio output device 7 based on the code at this point of time. If decision is made as to the passage to be taken according to the information, smooth travelling will be performed. |
