| 摘要 |
PURPOSE:To obtain the data with which a faulty area can be easily discriminated by setting previously a fault pattern and detecting the coincidence between this fault pattern and an input pattern. CONSTITUTION:When a sequence action has a fault and the coincidence is secured between either one of fault patterns set previously and an input signal change pattern, a stop signal is delivered to an address counter circuit 15 from a fault pattern detecting circuit 11. Thus the writing is discontinued at and after the next step to a read/write memory circuit 16. In a write mode of the circuit 16, the address numbers are written successively at and after No.1 every time the input signal pattern changes every step. When the writing proceeds up to an address step set previously to the circuit 15, the writing order is reset to No.1 and then carried out repetitively. Thus this sequential writing system is stopped if a falut pattern is produced. Therefore a specific area where a fault occurs is recorded to the memory. |
