NEC mPD789101 User Manual page 212

Figure 15-6. Flowchart from Non-Maskable Interrupt Request Generation to Acknowledgement
Figure 15-7. Timing of Non-Maskable Interrupt Request Acknowledgement
CPU processing Instruction
TMIF4
Figure 15-8. Acknowledging Non-Maskable Interrupt Request
Main routine
NMI request
(first)
212
CHAPTER 15 INTERRUPT FUNCTIONS
Start
WDTM4 = 1
(watchdog timer mode
is selected)
Yes
WDT
overflows
Yes
WDTM3 = 0
(non-maskable interrupt
is selected)
Yes
Interrupt request is generated
Interrupt processing is started
WDTM: Watchdog timer mode register
WDT: Watchdog timer
Instruction
First interrupt processing
NMI request
(second)
User's Manual U13045EJ2V0UM00
No
Interval timer
No
No
Reset processing
Save PSW and PC, and
jump to interrupt processing
Second interrupt processing
Interrupt processing
program