| 摘要 |
PROBLEM TO BE SOLVED: To reduce the communication cost for acquiring map data. SOLUTION: A control circuit 80 sets a destination, and positions a present location on the basis of operations at a key operating part 60. The map data indicating the present location is acquired by communications from a base station, and the map data is displayed on a liquid crystal display 50. The time intervals for acquiring the map data are shortened as the distance between the present location and the destination is shortened. By this, it is possible to reduce the times for acquiring the map data in comparison with the case of acquiring the map data every time the present location falls outside the range of the displayed map data. |
