| 摘要 |
PURPOSE:To secure the quick execution of an input/output action despite the breakdown of a peripheral controller of a certain system, by executing simultaneous input/output conrol for plural peripheral controllers to process only the first coming controller and to neglect the last coming controller. CONSTITUTION:In case a peripheral controller 2 rises a control start signal eariler than a peripheral controller 3, the controller 2 sets an RQ1 signal line 11 at 1. An input/output device 10 confirms 0 of a signal line 16 of an AP2 and sets a signal line 12 of AP1 at 1. The controller 2 can use the device 10 when the line 12 is set at 1. When an input/output action is over, the device 10 sets the line 12 at 0. The controller 2 sets the line 11 also at 0 when the line 12 is set at 0. When the line 12 is kept at 1, an answer is given only to an interface signal line group 14. |
