UPD784938 Datasheet, PDF (551/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 23 INTERRUPT FUNCTIONS
Figure 23-10. Interrupt Acknowledgment Processing Algorithm
Highest
No default priority among
macro service
requests?
Yes
Macro service
processing execution
Interrupt request
held pending
××IF = 1
Yes
No
Interrupt request?
××MK = 0
Yes
No
Interrupt mask released?
Yes
××ISM = 1
No
Macro service?
IE = 1
Yes
No
Interrupt enabled state?
Higher priority
No
than interrupt currently
being serviced?
Yes
Higher priority
No
than other existing interrupt
requests?
Yes
Highest default
priority among interrupt
No
requests of same
priority?
Yes
××CSE = 1
No
Yes
Context switching?
Interrupt request
held pending
Vectored interrupt
generation
Context switching
generation
Preliminary User’s Manual U13987EJ1V0UM00
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