Section 13 Watchdog Timer; Features - Renesas H8S/2368 Series Hardware Manual

Section 13 Watchdog Timer

The watchdog timer (WDT) is an 8-bit timer that outputs an overflow signal (WDTOVF) if a
system crash prevents the CPU from writing to the timer counter, thus allowing it to overflow.
At the same time, the WDT can also generate an internal reset signal.
When this watchdog function is not needed, the WDT can be used as an interval timer. In interval
timer operation, an interval timer interrupt is generated each time the counter overflows.
The block diagram of the WDT is shown in figure 13.1.
13.1

Features

• Selectable from eight counter input clocks
• Switchable between watchdog timer mode and interval timer mode
In watchdog timer mode
• If the counter overflows, the WDT outputs WDTOVF. It is possible to select whether or not
the entire chip is reset at the same time.
In interval timer mode
• If the counter overflows, the WDT generates an interval timer interrupt (WOVI).
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