| 摘要 |
PURPOSE:To offer a semiconductor memory device having various as well as inexpensive judging functions and a circuit system for a logical device having a memory function by devising the circuit so as to realize the semiconductor memory device having the self-diagnostic function. CONSTITUTION:The specific memory cell of a memory matrix 3 is selected by an address input signal AD. The information from a data input circuit 7 is inputted to a selected memory cell via a multiplexer 6 at the write cycle and the information of the selected memory cell is outputted to a data output circuit 8 via the multiplexer 6 at the read cycle. The self-diagnostic circuit 15 is connected to data lines D, D' and judges whether the write is performed correctly or incorrectly after the write of information. A row register circuit 16 and a column register circuit 17 fetch the row and column information having mis-write into the circuit by the control of a collating output line P and output the result of the judgement to an output control circuit 18 when the fetched information and the row and column information of the selected memory cell at that time are coincident with each other during the read cycle.
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