| 摘要 |
PURPOSE:To easily specify the area of a fault at occurrence of this fault by holding the contents of a register designating part and stopping this holding action when an error is detected in the output data given from a register. CONSTITUTION:A signal generating circuit 13 sends the clock signal inputted via a signal line 113 to a register 2 in accordance with the state value of a register 12. The register 2 holds the contents of a register designating part A of the microinstruction received from a microinstruction register 1 in response to the output signal received from the circuit 13. A diagnostic processor 3 decides the presence or absence of a parity error based on the state value of the register 12. Then the processor 3 sends a selection signal to the register 2 when the occurrence of the parity error is confirmed to stop the holding action of the register 2. In such a way, the contents of the part A can be obtained at occurrence of an error and therefore the area of the fault can be easily specified at occurrence of the fault. |
