UPD78F0411GA-GAM-AX Datasheet, PDF (450/564 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

CHAPTER 17 INTERRUPT FUNCTIONS
Figure 17-7. Interrupt Request Acknowledgment Processing Algorithm
Start
No
××IF = 1?
Yes (interrupt request generation)
No
××MK = 0?
Interrupt request held pending
Yes (High priority)
Yes
××PR = 0?
Yes
Interrupt request held pending
Any high-priority
interrupt request among those
simultaneously generated
with ××PR = 0?
No
No
IE = 1?
Interrupt request held pending
Yes
Vectored interrupt servicing
No (Low priority)
Any high-priority
interrupt request among
Yes
those simultaneously generated
with ××PR = 0?
No
Interrupt request held pending
Any high-priority
interrupt request among
those simultaneously
generated?
No
Yes
Interrupt request held pending
No
IE = 1?
Yes
ISP = 1?
Interrupt request held pending
No
Yes
Interrupt request held pending
Vectored interrupt servicing
××IF: Interrupt request flag
××MK: Interrupt mask flag
××PR: Priority specification flag
IE: Flag that controls acknowledgment of maskable interrupt request (1 = Enable, 0 = Disable)
ISP: Flag that indicates the priority level of the interrupt currently being serviced (0 = high-priority interrupt
servicing, 1 = No interrupt request acknowledged, or low-priority interrupt servicing)
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User’s Manual U18698EJ1V0UD