| 摘要 |
PURPOSE:To prevent a system down due to a break in electric power feed by dividing common peripheral equipments into a random number of blocks and then by providing an electric power source change-over circuit to every block. CONSTITUTION:Bus change-over circuit BSU21 and common peripheral equipment IOs231-23m constitute common peripheral equipment block 27, and bus change- over circuit BSU22 and common peripheral equipment IOs241-24n common peripheral equipment block 28. Common peripheral equipment block 27 is connected to electric power change-over circuit 29, and common peripheral equipment block 28 to electric power change-over circuit 30. Electric power change-over circuits 29 and 30, which are both connected to, for example, the A-system electric power source and B-system electric power source respectively, exercise change-over control over the electric power source system of either A- or B-system by change-over control signal SS supplied from CPU11 and CPU12 at need. Namely, one electric power source system, once running into trouble, is brought under the control of CPU connected to the other normal electric power source. |
