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Chapter 12 Interrupt Functions
12
Fig. 12-11 Example of Handling an Interrupt Request When an Interrupt Is Already Being Handled (2/2)
Main routine
Processing i
Vectored interrupt request k
(low priority)
Vectored interrupt request i
(low priority)
[Nesting 1] [Nesting 2]
Processing j
Processing k
Vectored interrupt request l (low priority): Pending
Processing l
Processing m
Vectored interrupt request n (low priority): Pending
Processing o
Vectored interrupt request p (low priority): Pending
Processing n
Processing p
Processing s
Processing q
Vectored interrupt request r (low priority): Pending
Processing r
EI
Setting EI, ISP to 1
EI
Vectored interrupt
request j
(low priority)
Vectored interrupt
request j
(high priority)
Vectored interrupt request m
(low priority)
Vectored interrupt request o
(high priority)
Vectored interrupt request q
(high priority)