user manual

Interrupts
General Release Specification MC68HC05RC16 — Rev. 3.0
40 Interrupts MOTOROLA
Figure 4-1. Interrupt Processing Flowchart
N
N
RESTORE REGISTERS
FROM STACK: CCR, A, X, PC.
LOAD PC FROM
APPROPRIATE
VECTOR.
SET I BIT IN
CC REGISTER.
STACK
PC, X, A, CCR.
CLEAR
IRQ
REQUEST
LATCH.
FETCH NEXT
INSTRUCTION.
EXECUTE
INSTRUCTION.
Y
Y
N
I BIT
IN CCR
SET?
SWI
INSTRUCTION
?
N
Y
RTI
INSTRUCTION
?
Y
FROM
RESET
Y
INTERNAL
CMT
INTERRUPT
N
N
Y
INTERNAL
CORE TIMER
INTERRUPT
IRQ/PORT B
EXTERNAL
INTERRUPTS
EIMSK
CLEAR?
Y
N
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