| 摘要 |
PURPOSE:To improve the information processing efficiency by allocating the input/output requests if delivered from plural input/output devices to the input/ output ports according to the prescribed priority. CONSTITUTION:When an input/output request is sent to a priority encoder 24 from either one of input/output devices #1-#4, the input/output device delivered with the input/output request and having the highest priority is detected out of a priority register 23. Then the information on the register 23 is sent to multiplexers 26A and 26B and one of connection circuits D-1-D-4 to a transmission/reception circuit 25 is selected and allocated to input/output ports 22A and 22B. Here if the input/output requests are received from plural input/output devices of the same priority, these requests are equally allocated. Then the priority is raised temporarily by a count-up means 27 in such a case an input/output device is not connected to the corresponding input/output port since this port is not available. In such a way, plural input/output devices of the same priority are equally allocated to the input/output ports respectively. |
