MC68HC08AZ16 Datasheet, PDF (165/527 Pages) Motorola, Inc – HCMOS Microcontroller Unit

External Interrupt Module (IRQ)
.
FROM RESET
YES
I BIT SET?
NO
INTERRUPT?
NO
YES
STACK CPU REGISTERS.
SET I BIT.
LOAD PC WITH INTERRUPT VECTOR.
FETCH NEXT
INSTRUCTION.
SWI
YES
INSTRUCTION?
NO
RTI
YES
INSTRUCTION?
NO
UNSTACK CPU REGISTERS.
EXECUTE INSTRUCTION.
Figure 4. IRQ interrupt flowchart
MC68HC08AZ32
164
External Interrupt Module (IRQ)
4-irq
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