JPS5658608A - Electronic odometer - Google Patents

Abstract

PURPOSE: To give the correct distance covered irrespective of the breaking of a power source by a constitution wherein the data obtained by adding up the detection signals from a distance sensor are stored in two places of a nonvolatile memory and selected therefrom on the basis of the relations in amount of the data and thereby the addition of the distance covered is renewed sequentially.

CONSTITUTION: The signal of the distance sensor 1 which generates one pulse every time when a fixed distance, for instance, the distance of 100m is covered is inputted in a microcomputer 2 through the intermediary of the signal of a quartz oscillator 3 and written in two regions of the nonvolatile memory 4 as data A and B. The distance data A and B added up in the memory 4 are read out and, when the rela- tion of the data is A>B, the data of B+1 are written in. Then the data A and B are written in renewedly and the distance covered is indicated in an indicator 6 through the intermediary of a decoder driver 7. If the relation is A<B, the data of A+1 is written in and later the writing-in and indication of A and B are conducted. By this process being repeated, the correct indication of the distance covered is performed constantly even when there occurs the breaking of the power source.

COPYRIGHT: (C)1981,JPO&Japio