Which kind of interrupt has the highest priority on 8086 processors?

Problem Detail: 

Which of the following interrupts has the highest priority in 8086 micro-processor:

1. Overflow,
2. NMI or
3. Type 255?

The book I read suggests that type 255 has highest priority. But most of the searches on google showed that it is NMI. Which is true?

Asked By : Pradeep

Answered By : Gene

The Intel manual for 8086 on page 2-23's diagram and also in the text says that internally generated interrupts are processed before hardware. It says in particular an overflow is processed as part of the instruction that generated the over flow, and hardware interrupts aren't checked until instructions are complete. So overflow is the answer.

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Question Source : http://cs.stackexchange.com/questions/23696