| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to discriminate whether the present position is located in areaz wherein telephone communication is possible or not readily by displaying the road map and the telephone service area obtained from a memory means and the present position obtained by a present-position detecting means on a display means. SOLUTION: The map data and the telephone service area data, which are operated in a CPU 10 based on the output of an azimuth sensor 1 and a distance sensor 2, corrected based on the data from a GPS receiver 5 and correspond to the present position, are read out of a CD-ROM 7 by a CD-ROM drive 6. The data are stored into a memory (DRAM) 12 through a communication interface 18. A part of the stored map data and telephone service area data are read out by the CPU 10 and converted into the image data with an image processor 15. The data are written into an image memory 16. The image data are converted into the color signal in an RGB converting circuit 17. The signal is sent into a liquid crystal display 8A, and the map and the telephone service area in the specified range are displayed with the present position as the center. |
