HD6432345 Datasheet, PDF (421/907 Pages) Hitachi Semiconductor – H8S/2345 F-ZTAT Hardware Manual

11.3.2 Interval Timer Operation
To use the WDT as an interval timer, clear the WT/IT bit in TCSR to 0 and set the TME bit to 1.
An interval timer interrupt (WOVI) is generated each time TCNT overflows, provided that the
WDT is operating as an interval timer, as shown in figure 11.5. This function can be used to
generate interrupt requests at regular intervals.
TCNT count
H'FF
Overflow
Overflow
Overflow
Overflow
H'00
WT/IT=0
TME=1
WOVI
WOVI
WOVI
WOVI
Time
Legend
WOVI: Interval timer interrupt request generation
Figure 11.5 Interval Timer Operation
11.3.3 Timing of Setting Overflow Flag (OVF)
The OVF flag is set to 1 if TCNT overflows during interval timer operation. At the same time, an
interval timer interrupt (WOVI) is requested. This timing is shown in figure 11.6.
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