Non-Maskable Interrupt Request Acknowledgment Flowchart - NEC mPD780208 Subseries User Manual

Figure 16-9. Non-Maskable Interrupt Request Acknowledgment Flowchart
Figure 16-10. Non-Maskable Interrupt Request Acknowledgment Timing
CPU processing Instruction
TMIF4
TMIF4: Watchdog timer interrupt request flag
348
CHAPTER 16 INTERRUPT AND TEST FUNCTIONS
Start
WDTM4 = 1
(with watchdog timer
mode selected)?
Yes
Overflow in WDT?
Yes
WDTM3 = 0
(with non-maskable
interrupt request
selected)?
Yes
Interrupt request generation
WDT interrupt servicing?
Yes
Interrupt control
register unaccessed?
Yes
Interrupt
service start
WDTM: Watchdog timer mode register
WDT: Watchdog timer
Instruction
Interrupt request generated during this interval is acknowledged at
User's Manual U11302EJ4V0UM
No
Interval timer
No
No
Reset processing
No
Interrupt request
held pending
No
PSW and PC save, jump
to interrupt servicing
Interrupt servicing
program
.