BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and aspects of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings in which:
FIG. 1 is a block diagram schematically illustrating an example of the configuration of a vehicle control system including an electronic control unit (ECU) according to a first embodiment of the present invention;
FIG. 2 is a block diagram schematically illustrating an example of the configurations of a bus transceiver, a level adjusting circuit, and communication controllers illustrated in FIG. 1;
FIG. 3 is a timing chart schematically illustrating CAN communications via an AND gate illustrated in FIG. 1;
FIG. 4A is a flowchart schematically illustrating operations of the communication controller installed in a main microcomputer illustrated in FIG. 1;
FIG. 4B is a flowchart schematically illustrating operations of the communication controller installed in a sub microcomputer illustrated in FIG. 1;
FIG. 5 is a block diagram schematically illustrating electrical configurations of an ECU according to a second embodiment of the present invention;
FIG. 6 is a circuit diagram schematically illustrating electrical configurations of an ECU according to a third embodiment of the present invention;
FIG. 7A is a flowchart schematically illustrating a direct communication start task to be executed by a main microcomputer according to the third embodiment;
FIG. 7B is a flowchart schematically illustrating a message task to be repeatedly executed by a main microcomputer according to the third embodiment;
FIG. 8 is a block diagram schematically illustrating electrical configurations of an ECU according to a fourth embodiment of the present invention;
FIG. 9 is a block diagram schematically illustrating electrical configurations of an ECU according to a fifth embodiment of the present invention;
FIG. 10 is a block diagram schematically illustrating electrical configurations of an ECU according to a sixth embodiment of the present invention;
FIG. 11 is a block diagram schematically illustrating electrical configurations of an ECU according to a seventh embodiment of the present invention;
FIG. 12 is a block diagram schematically illustrating electrical configurations of an ECU according to an eighth embodiment of the present invention; and
FIG. 13 is a flowchart schematically illustrating a memory rewriting task to be executed by a main microcomputer according to the eighth embodiment.