| 摘要 |
PROBLEM TO BE SOLVED: To provide useful information regarding the acquisition of map information in communication. SOLUTION: A control section 12 functions as an update information acquisition means, controls a communication section 24 for communicating with an information center 40, and acquires the most recent update period of the most recent district map information of the information center 40 corresponding to already existing district map information of a map storage section 18 and an update count from the already existing district map information to the most recent district map information. The control section 12 associates the acquired most recent update period and update count with district specific information for specifying the district map information concerned for storing at an update information storage section 28. The control section 12 acquires the amount of data of the differential data between the already existing district map information and the most recent district map information and a supply charge. These pieces of information are listed for display according to a user's operation. A district selected by a user from the list display is registered as a candidate district, and the differential data of the candidate district is acquired from the information center 40. COPYRIGHT: (C)2004,JPO |
