Navigation apparatus with non-volatile memory for return to initial

Abstract

A navigation apparatus has an input unit (1), a CPU (2), a display unit (3) and a memory unit (4), the memory unit (4) being a memory such as a CD-ROM in which network data of geographical points, namely destinations and present locations, and information are stored in advance. Also stored are map data (10), an intersection list (11), a destination list (12), road data (13) and a region name list (14), etc. When a destination is designated by an input from the input means (1), the CPU (2) performs an exchange with a program, stored in a ROM (9a), in order to set information for travel to the destination by course exploration in accordance with each geographical point stored in the memory unit (4). This information is stored in a memory such as a RAM (9b). In an embodiment, the RAM (9b) is provided with a non-volatile area for storing departure-point data (east longitude, north latitude, etc.). When an input is made by a reset switch in entering a departure point, the data in this non-volatile area can be rewritten. Data written in are preserved until the reset switch is pressed again and a geographical point is entered. Data will not be erased even if an ignition switch is turned off.