| 摘要 |
PURPOSE:To display the peripheral area of a present position on a display device, to confirm the condition of the peripheral area and to improve the function of navigation by making a map displayed on a display device revisable, if necessary, regardless of the normal or the abnormal of GPS data. CONSTITUTION:An arbitrary time map selection display means 6c forcedly displays the selected map replacing with the map while displaying on the display device 5, when an optional map is manually selected by the key input of an input device 4, regardless of whether the judgement of a data accuracy detection means 6b is normal or not. Then, the display of the display device 5 is restored automatically when interruption by key input is not present for a fixed time after the map is selected and the GPS data is returned from the abnormal state to the normal state, and, thereafter, the present position found by the normal GPS data and the map containing the present position are displayed on the display device 5. |
