Fujitsu F2MCTM-16LX Hardware Manual page 221

Clearing watchdog timer
• When "0" is written once again to the watchdog timer control bit (WDTC: WTE) within the interval time
after starting the watchdog timer, the watchdog timer is cleared. If the watchdog timer is not cleared
within the interval time, it overflows and the CPU is reset.
• A reset, or transitions to the standby modes (sleep mode, stop mode, watch mode, timebase timer mode)
clear the watchdog timer.
• During operation in the timebase timer mode or watch mode, the watchdog timer counter is cleared.
However, the watchdog timer remains in the activation state.
• Figure 12.4-2 shows relationship between clear timing and interval time of watchdog timer. The interval
time varies with the timing of clearing the watchdog timer.
CHAPTER 12 WATCHDOG TIMER
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