| 摘要 |
PURPOSE:To improve the data processing capacity of a channel by executing a data transfer of other channel, while waiting for an MS access end by a CCW fetch of some channel. CONSTITUTION:A staging part 12 is divided into two of A and B, and a data transfer request and a CCW fetch request are brought to staging to a part A and B, respectively. In this state, when waiting an access end by an MS access of a CCW fetch, if a data transfer request exists in the part A, a priority part executes it. In this case, a CS address to a CCW fetch request which is being executed is saved in a CS address holding part 28. When the MS access has been ended, as soon as a data transfer processing which is being executed by a processor at present is ended, the CS address which has been held in the holding register part 28 is delivered to a control part 14, and a CCW fetch processing is restarted. |
