| 摘要 |
PURPOSE:To make the processing high-speed, by detecting that an interrupt request exists and that restores interrupt inhibition designating information permits interruption, when a return instruction for information saved because of the interruption is executed. CONSTITUTION:When an execution of return instruction is started, previously saved program execution state PSW information is read from a stack. When an interruption inhibition mode is designated in read information, it is restored by a CPU to set a new interruption inhibiting mode. If this information permits an interruption after it is tested and restored, it is tested whether an interruption request exists or not. If the interruption request exists, the control is transferred to an interruption processing program. Thus, CPU information is not restored and saved for the reinterruption after the return from the interruption, and the processing is performed in a high speed. |
