| 摘要 |
PURPOSE:To shorten the breakdown period by switching automatically faulty one of plural function parts to a redundant function part. CONSTITUTION:A circuit substrate 12 for redundancy having equivalent function is provided to the substrates 11A-11C having equivalent functions. The address data allotted to these substrates are stored in a scramble memory 13, and an access is given to the memory 13 under the control of a CPU14 to read the address data. Then circuit substrates 11A-11C and 12 are selected based on those address data, and at the same time the data are supplied to these substrates. Each output of substrates 11A-11C is compared with the output of the substrate 12 to diagnose whether substrates 11A-11C and 12 are normal or not respectively. If a fault arises, the address data in the memory 13 is updated under the control of the CPU14 to exchange faulty one of substrate 11A-11C with the substrate 12. |
