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CHAPTER 16 INTERRUPT AND TEST FUNCTIONS
User’s Manual U11302EJ4V0UM
Figure 16-9. Non-Maskable Interrupt Request Acknowledgment Flowchart
WDTM: Watchdog timer mode register
WDT:
Watchdog timer
Figure 16-10. Non-Maskable Interrupt Request Acknowledgment Timing
WDTM4 = 1
(with watchdog timer
mode selected)?
Overflow in WDT?
WDTM3 = 0
(with non-maskable
interrupt request
selected)?
Interrupt request generation
WDT interrupt servicing?
Interrupt control
register unaccessed?
Interrupt
service start
Interrupt request
held pending
Reset processing
Interval timer
No
Yes
Yes
No
Yes
No
Yes
No
Yes
No
Start
Instruction
Instruction
CPU processing
TMIF4
PSW and PC save, jump
to interrupt servicing
Interrupt servicing
program
Interrupt request generated during this interval is acknowledged at .
TMIF4: Watchdog timer interrupt request flag