HD6475328-CP10 Datasheet, PDF (250/459 Pages) Hitachi Semiconductor – original Hitachi CMOS microcomputer unit (MCU)

Section 13 Watchdog Timer
13.1 Overview
The H8/532 has an on-chip watchdog timer (WDT) module. This module can monitor system
operation by requesting a nonmaskable interrupt if a system crash allows the timer count to
overflow.
When this watchdog function is not needed, the WDT module can be used as an interval timer. In
the interval timer mode, an IRQ0 interrupt is requested at each counter overflow.
The WDT module is also used in recovering from the software standby mode.
13.1.1 Features
The basic features of the watchdog timer module are summarized as follows:
• Selection of eight clock sources
• Selection of two modes: watchdog timer mode and interval timer mode
• Counter overflow generates an interrupt request
NMI request in the watchdog timer mode; IRQ0 request in the interval timer mode.
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