JPS57199912A - Integrating distance meter - Google Patents

Abstract

PURPOSE:To obtain a device of high reliability despite the inadvertent use of an easy-to-erase programmable read-only memory by so forming the device that majority logics are adapted to writing and reading in a nonvolatile memory. CONSTITUTION:A nonvolatile memory 2 which is written with the signals of the same logic sequentially in the plural bits of respective addresses in order of address numbers and stores an integrated distance at the number of the final address position where the wirting finishes is provided. The logic of the majority of the plural bits read out from the same address position of said memory 2 is used as the signal logic of that address position. A register which sets the value of the integrated traveling distance determined by the read-out from the memory 2 at every turning on of a key switch is provided to a vehicle and further the traveling distance is calculated from the vehicle speed signal, and at every unit value, the unit numerical value is added to the contents of said register so that in the address shown by the new contents of the register the signal of the same logic is written into the plural bits of the non-volatile memory.