Patent ID: 6678586
Filing Date: 2004-01-13
Classification: B60W,G06F

Abstract:
A vehicle built-in electronic control apparatus fed from a vehicle built-in battery through a power switch, comprising:a main CPU; a first nonvolatile memory for the main CPU, storing at least first control programs and control constants of the controlled vehicle, adapted to be written from an external tool; a sub CPU; a second nonvolatile memory for the sub CPU, storing second control programs; a RAM memory, for calculation processing of the sub CPU; and a serial-parallel converter for full duplex two-way serial communication for mutually conducting data communications between the main CPU and the sub CPU in operation of the controlled vehicle; control constant sending means for sending the control constants stored in the first nonvolatile memory to the sub CPU when the contents of the first nonvolatile memory have been changed at the time of starting operation of the controlled vehicle; irregular data sending means for sending the sending data as irregular data when a data request from the receiving side CPU to the sending side CPU is present; and regular data sending means for regularly sending the sending data as regular data by the sending side CPU even when the data request from the receiving side CPU to the sending side CPU is absent; wherein: at the time of starting the operation of the controlled vehicle, only a part of the control constants in the first nonvolatile memory is transferred, through the serial-parallel converter, to the second RAM memory; and then the sub CPU performs a predetermined calculation based on: the contents of the second control programs of the second nonvolatile memory, and the contents of the control constants transferred to the second RAM memory from the first nonvolatile memory.