| 摘要 |
PURPOSE:To inform the error of an input and output device detected by a central processing unit to a channel processor with less overhead by erecting a prescribed flag in a corresponding sub-channel when an unit having no func tion for resetting the input and output device directly detects the error with respect to the input and output device and performing the resetting and an the error processing of a channel processor. CONSTITUTION:When the lock byte 13 of the sub-channel 12 is not cleared but remains, the central processing unit 1 enforcedly clears the lock byte 13 and changes the contents, thereafter, sets a bit indicating that the abnormality is detected on the sub-channel 12 and enqueues to a queue similarly to the case when an ordinary input and output request is generated in this sub-channel. The channel processor 3 dequeues this queue to start the processing, and when an error condition is recognized, the input and output device 7 corresponding to the sub-channel 12 is selectively reset. |
