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3.9.2 Interrupt Stack Operation
The value of PC and PS is saved and revived in the area shown by SSP. After an
interrupt, PC is stored in the address indicated by the SSP, and PS is stored in the
address (SSP+4).
■ Interrupt Stack
Figure 3.9-1 shows the example of the interrupt stack.
Figure 3.9-1 Interrupt stack operation diagram
[Example] [Befor interrupt] [After interrupt]
SSP SSP
Memory
80000000
H
7FFFFFFC
H
PS
7FFFFFF8
H
7FFFFFF8
H
80000000
H
80000000
H
7FFFFFFC
H
7FFFFFF8
H
PC