| 摘要 |
PURPOSE:To execute an input/output instruction and maintenance and diagnosis of a central processing unit by connecting the central processing unit and a service processor with a single interface line and also providing a channel device to the low-order of the service processor. CONSTITUTION:A CPU1 has a CPU side interface circuit (SVA)11 and the SVA is connected to a service processor (SVP) interface line 5. An IO processor (IOP)8 is connected with the CPU1 by the interface line 5. The IOP8 has an SVP2, a channel device (CH)3 and a buffer memory (RAM)7. The SVP2 has an SVP side interface circuit (SVU)21. A device (IO)6 is connected to the CH3. Moreover, the SVP2 and the CH3 in the IOP8 are operated in time division under one processor. Thus, the input/output instruction and the maintenance/disagnosis of the CPU are executed. |
