Non-Maskable Interrupt Request Acknowledge Operation - NEC PD78056F User Manual

CHAPTER 21 INTERRUPT AND TEST FUNCTIONS
Figure 21-12. 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>
1 Instruction Execution
(b) If two non-maskable interrupt requests are generated during
non-maskable interrupt servicing program execution
Main Routine
NMI Request <1>
1 Instruction Execution
NMI Request <2>
NMI Request <1> executed.
NMI Request <2> held
NMI Request <2>
NMI Request <3> held.
NMI Request <3>
Held NMI Request <2> processed.
NMI Request <3> is not received.
Even if more than 2 NMI requests are generated,
they can only be received 1 time.
NMI Request <1> executed.
NMI Request <2> held.
Held NMI Request <2> processed.
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