HD6432345 Datasheet, PDF (410/907 Pages) Hitachi Semiconductor – H8S/2345 F-ZTAT Hardware Manual

Section 11 Watchdog Timer
11.1 Overview
The H8S/2345 Series has a single-channel on-chip watchdog timer (WDT) for monitoring system
operation. The WDT outputs an overflow signal (WDTOVF)* if a system crash prevents the CPU
from writing to the timer counter, allowing it to overflow. At the same time, the WDT can also
generate an internal reset signal for the H8S/2345 Series.
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.
11.1.1 Features
WDT features are listed below.
• Switchable between watchdog timer mode and interval timer mode
• WDTOVF output* when in watchdog timer mode
If the counter overflows, the WDT outputs WDTOVF.* It is possible to select whether or not
the entire H8S/2345 Series is reset at the same time. This internal reset can be a power-on
reset or a manual reset.
• Interrupt generation when in interval timer mode
If the counter overflows, the WDT generates an interval timer interrupt.
• Choice of eight counter clock sources.
Note: * The WDTOVF pin function is not supported by the F-ZTAT version.
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