NuMicro® NUC029LEE/NUC029SEE
32-bit Arm
®
Cortex
®
-M0 Microcontroller
Aug, 2018
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unless chip is reset.
WWDT Compare Match Interrupt
During down counting by the WWDT counter, the WWDTIF is set to 1 while the WWDT counter
value (WWDTCVAL) is equal to WINCMP value and WWDTIF can be cleared by software; if
WWDTIE is also set to 1 by software, the WWDT compare match interrupt signal is generated
also while WWDTIF is set to 1 by hardware.
WWDT Reset System
When WWDTIF is generated, user must reload WWDT internal counter value to 0x3F by writing
0x00005AA5 to WWDTRLD, and also to prevent WWDT counter value reached to 0 and generate
WWDT reset system signal to info system reset.
If current WWDTCVAL value is larger than WINCMP value and user writes 0x00005AA5 to the
WWDTRLD register, the WWDT reset system signal will be generated immediately to cause chip
reset also.
0x
3F
WWDTCVAL > WINCMP
W
IN
C
M
P
WWDTCVAL <= WINCMP
0x
0
WWDTCVAL
Reset system when
WWDTCVAL = 0
Write WWDTRLD 0x5AA5 here will
reset system
Write WWDTRLD 0x5AA5 here will reload
WWDTCVAL to 0x3F
Figure 6.11-3 Window Watchdog Timer Reset and Reload Behavior