Non-Maskable Interrupt Request Acknowledge Operation - NEC PD78081(A) User Manual

CHAPTER 12 INTERRUPT FUNCTION
Figure 12-10. Non-Maskable Interrupt Request Acknowledge Operation
(a) If a new non-maskable interrupt request is generated during
non-maskable interrupt servicing program execution
Main Routine
NMI Request
1 Instruction
Execution
(b) If two non-maskable interrupt requests are generated during
non-maskable interrupt servicing program execution
Main Routine
NMI Request
1 Instruction
Execution
NMI Request
NMI Request
NMI Request
Reserved NMI Request Processing
NMI Request
NMI
NMI Request
Request
NMI Request
NMI
Request
Reserved NMI Request
Processing
Cannot acknowledge NMI Request
(Although multiple NMI requests may
be generated twice or more, they
can only be acknowledged once.)
Execute
Reserve
Execute
Reserve
Reserve
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