| 摘要 |
PURPOSE:To shorten the time when peripheral devices are in the interruption pending state and to improve the effective use rate of peripheral devices, by making it possible that another central processing device executes the interruption processing instead of a central processing device which indicates the start. CONSTITUTION:When indicated operations are completed, a peripheral device sets an all device designation flip-flop (FF) 261 and requests an interruption and sets an interruption permission waiting FF 270. Since all device designation FF is set, all central processing devices receive this interruption request, and they start an interruption permission transmitting circuit if their own interruption inhibiting FFs 170 are reset. In case that plural central processing devices are in the interruption acceptable state, they transmit bus use requests, and a central processing device to which the use permission of the bus is given as the result of the priority control due to a bus controller connected to the bus returns the interruption permission to the peripheral device. |
