| 摘要 |
PURPOSE:To decide on which of processors gets out of order and to determine the fault position by providing a method which detects an error by making a comparison between outputs of two processing circuits of the same constitution and is stored with the number of clocks up to that point. CONSTITUTION:Outputs of processing parts 2 and 3 are compares by identity check circuit 11, and when nonidentity is found by circuit 11, control part 21 is started via nonidentity error FF12 and AND circuit 14 to start execution of a diagnostic program through in-process-of-diagnosis display FF13. Processing parts 2 and 3 execute the diagnostic program and their outputs are compared by circuit 11, so that addition will be done every time counter 16 counts them. Once an error detected by circuit 11, the update of counter 16 is interrupted and only processing part 2 continues to execute the diagnostic program. As a result, when the processing result agrees with a previously-fixed correct value, processing part 3 is considered to get out of order and when disagreeing, processing part 2 is judged to be in trouble. In register 17, the number of execution steps indicated by the diagnostic program is set and it is compared with the value of counter 16 by a count check circuit to decide upon the number of steps of fault points. |
