Resets and Interrupts
MC68HC908GT16 MC68HC908GT8 Data Sheet, Rev. 3
140
Freescale Semiconductor
Figure 13-6. Interrupt Processing
The LDA opcode is prefetched by both the INT1 and INT2 RTI instructions. However, in the case of the
INT1 RTI prefetch, this is a redundant operation.
NOTE
To maintain compatibility with the M6805 Family, the H register is not
pushed on the stack during interrupt entry. If the interrupt service routine
NO
NO
NO
YES
NO
NO
YES
NO
YES
YES
FROM RESET
BREAK
INTERRUPT
II BIT SET
IRQ
INTERRUPT
ICG
INTERRUPT
FETCH NEXT
INSTRUCTION
UNSTACK CPU REGISTERS
STACK CPU REGISTERS
SET I BIT
LOAD PC WITH INTERRUPT VECTOR
EXECUTE INSTRUCTION
YES
YES
YES
OTHER
INTERRUPTS
NO
SWI
INSTRUCTION
RTI
INSTRUCTION