| 摘要 |
PURPOSE:To secure reliability and improve economy by automatically arranging a stand-by memory block in the address of a faulty memory block if one of plural memory blocks becomes faulty CONSTITUTION:A microprocessor block 1 and memory blocks 2-4, and the stand-by memory block 5 are connected by a system bus 6, and the memory blocks 2-4 and stand-by memory block 5 are further connected by a faulty block address bus 7. If trouble occurs to one of the memory blocks 2-4, the stand-by memory block 5 is arranged automatically in the address of the faulty memory block and operates as a substitute. Consequently, the reliability of the system is improved without decreasing the economy as compared with the complete doubling of the memory. |
