| 摘要 |
PURPOSE:To make a virtual current point coincident with a real point by inputting outputs of a vehicle speed sensor and an azimuth sensor to a display control part and calculating the current point. CONSTITUTION:A device consists of the vehicle speed sensor 11, the azimuth sensor 10, a display device 20, and the display control part 14 which displays a run tack on the screen of the display device 20 together with a map. Then, when the interruption of a vehicle speed pulse is detected, a counted value is increased and the azimuth data from the sensor 10 is read in at the same time. The current point is calculated from the azimuth data and the counted value of vehicle speed pulses and the display address of a video RAM 19 is so set in a graphic display controller (GDC) 18 that the current point is in the center of the screen. Further, when there is undulations in a course and the current point is not coincident with a mark point actually although the current point is coincident with the mark point on the map, the display address of the GDC 18 is not updated and the map is left as it is and then moved after the counted value becomes coincident, so that the position on the map and actual position are corrected at the mark point. |
