Patent ID: 6108598
Filing Date: 2000-08-22
Classification: B60R,F02D,G05B,G06F

Abstract:
A vehicle-onboard control system installed on a motor vehicle for controlling at least one device mounted on said vehicle, comprising:a central processing unit (11) for executing a control program by using various control variables to thereby control said device (40) mounted on said motor vehicle;a writable non-volatile read-only memory (12) for storing said control program;a backup random access memory (14) for storing said control variables;a backup power supply (30) for supplying electric power to said backup random access memory (14);a bootstrap program (13) for operating said central processing unit (11) to allow said control program to be rewritten;an address changing interface (15) for locating said bootstrap program (13) at an address executable by said central processing unit (11) upon rewriting of said control program; anda memory rewriting device (50) for outputting a rewrite signal (A) for actuating said address changing interface (15) and a command signal (C) for activating said bootstrap program (13);wherein an initialization flag (FN) is provided in said backup random access memory 14) adapted to be set by said bootstrap program (13) in response to said command signal (C) upon rewriting of the said control program; andwherein said control program responds to the set state of said initialization flag (FN) upon activation of said control program after having been rewritten, to thereby initialize said control variables stored in said backup random access memory (14).