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Preliminary User’s Manual U17566EE1V2UM00
Chapter 15 Watchdog Timer (WDT)
The Watchdog Timer is used to escape from a system deadlock or program
runaway. If it is not restarted within a certain time, the Watchdog Timer flows
over and interrupts or even resets the microcontroller.
15.1 Overview
The Watchdog Timer contains an up-counter that is driven by the Watchdog
Timer clock WDTCLK. This clock can be derived from the main oscillator, the
ring oscillator, or the sub oscillator. It’s frequency can be identical with the
frequency of the source clock or a fraction thereof.
Features summary
The Watchdog Timer
• can generate the non-maskable interrupt NMIWDT
• can generate a hardware reset by means of the internal signal RESWDT
• has a programmable running time (set in terms of 2
n
multiples of WDTCLK
periods)
• is specially protected against inadvertent setup changes
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