Fujitsu MB91191 Manual De Usuario

50

CHAPTER 3  CPU

Figure 3.9-2 shows the example of multiple EIT processing.

Execution sequence of handler

Factor

1 

Reset 

*1

2 

Undefined instruction exception

3 

Step trace trap 

*2

4 

INTE instruction 

*2

5 

NMI (for user) 

6 INT 

instruction

7 User 

interrupt

8 

Coprocessor absent trap

Coprocessor error trap

*1: Other factors are abandoned. 
*2: If the INTE instruction is executed in steps, only EIT of the step trace trap generates 

INTE instruction.
The factor by INTE is disregarded.

[Example]

 

(High) NMI generation

Priority level

(Low) INT instruction execute

Next execute

First execute

INT instruction handler 

NMI handler

Main routine