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FUJITSU MB91F109 FR30 User Manual

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2.8 EIT (Exception, Interrupt, and Trap)

Figure 2.8.2 shows an example of multiple EIT processing.

Figure 2.8-2 Example of Multiple EIT Processing

Table 2.8-5 EIT Handler Execution Order

Handler execution order

Event

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 nonexistent trap
Coprocessor error trap

*1:

The other EIT events are discarded.

*2:

The INTE instruction cannot be used in an environment where a step-trace-trap
EIT event occurs.

Main routine

NMI handler

INT instruction
handler

Priority

(High) NMI occurrence

(Low) INT instruction
execution

Executed first

Executed next