摘要 |
A control system comprises an interrupt controller, having vector access signal output mechanism for outputting a vector access signal, which is activated when a start address is read out from a vector holder, and a central processing unit (CPU), comprising a present mask holder, which holds a present mask level, and a previous mask holder, which holds a previous mask level, wherein the CPU compares the interrupt level and the present mask level, and, when the interrupt level is higher than the present mask level, copies a value of the present mask level holder into the previous mask level holder, reads out a start address of an interrupt processing program corresponding to an accepted interrupt request from the vector holder, starts executing the interrupt processing program, and copies the interrupt level into a present mask level holder by means of an activated vector access signal.
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