Cyclical reset of vehicular microcomputers for economic error immunity

Claim 1

In a system comprising a microcomputer for controlling engine-speed-dependent operation of equipment of an internal combustion engine, of a motor vehicle, in response to operation conditions of said engine represented by electrical signals, said signals including at least one sequence of repetitive signals having a repetition rate not less than and synchronizing with the rate of revolution of a rotary body continuously dirven by said engine, said repetitive signals of said sequence being generated by a signal source having a rotary component body and an electrical output connection, and said microcomputer having a reset input for putting said microcomputer into a predetermined state suitable for beginning a computer operation, the improvement comprising: means for providing, by an electrical circuit connected to said signal source output connection, a reset signal to said reset input of said mircrocomputer in response to each of said repetitive signals of said sequence, whereby the vulnerability by error of said system for controlling equipment of said engine is limited, for each error, to a duration not exceeding one revolution of said rotary component of said signal source.