| 摘要 |
PURPOSE:To attain the self-diagnosis of the function of a watch dog timer itself and identification of a microcomputer to generate a runaway with the mutual monitoring of two microcomputers by providing first and second watch dog timer circuits. CONSTITUTION:At respective microcomputers 1 and 2, watch dog timer circus 4 and 6 are respectively and individually provided, watch dog pluse interrupting circuits 3 and 5 operated by watch dog testing signals WT1 and WT2 from other microcomputers mutually are respectively provided and further, the resetting signal output of the watch dog timer circuits 4 and 6 is mutually monitored at other microcomputer side. Thus, the self-diagnosis of the watch dog timer circuit can be executed, it is detected that other microcomputers are mutually reset, the microcomputers to generate the runaway can be identified, and therefore, when one side microcomputer only runs away, the control action of the system can be maintained by other microcomputers. |
