ENGINE START MANAGEMENT IN COMPUTER SYSTEM FOR AUTOMOBILE

摘要

PROBLEM TO BE SOLVED: To provide an efficient and safe method for shutting down the computer based system of a vehicle during engine startup while retaining the contents stored in a volatile random access memory. SOLUTION: The external low power microprocessor of a main processor board 10 turns off a main voltage regulator 27 which supplies a plurality of limiting voltages to the main processor board 10 in order to reduce power demands. The main processor board 10 saves the condition of a predetermined peripheral device in the volatile RAM 15 and turns off the peripheral device. A main processor 13 shifts to a suspended mode that is a state in which it waits for an actuation signal from the low power microprocessor. A secondary voltage regulator 50 is turned on to supply power to the volatile RAM 15 when the main voltage regulator 27 is turned off.