Data Sheet

NUC123
May 3, 2017 Page 57 of 99 Rev.2.04
NUC123 SERIES DATASHEET
Watchdog Timer (WDT) 6.9
6.9.1 Overview
The purpose of Watchdog Timer (WDT) is to perform a system reset when system runs into an
unknown state. This prevents system from hanging for an infinite period of time. Besides, this
Watchdog Timer supports the function to wake-up system from Idle/Power-down mode.
6.9.2 Features
 18-bit free running up counter for WDT time-out interval
 Selectable time-out interval (2
4
~ 2
18
) and the time-out interval is 1.6 ms ~ 26.214 s if
WDT_CLK = 10 kHz.
 System kept in reset state for a period of (1 / WDT_CLK) * 63
 Supports selectable WDT reset delay period, including 1026、130、18 or 3 WDT_CLK reset
delay period
 Supports to force WDT enabled after chip powered on or reset by setting CWDTEN in
Config0 register
 Supports WDT time-out wake-up function only if WDT clock source is selected as 10 kHz.