Datasheet

Section 13 Watchdog Timer (WDT)
Rev. 6.00 Mar. 18, 2010 Page 475 of 982
REJ09B0054-0600
TCNT value
H'00
Time
H'FF
WT/IT=0
TME=1
WOVI
Overflow Overflow Overflow Overflow
Legend:
WOVI: Interval timer interrupt request generation
WOVI WOVI WOVI
Figure 13.3 Interval Timer Mode Operation
13.4.3 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 13.4.
When NMI request is chosen in watchdog timer mode for WDT_1, TCNT overflow sets the OVF
flog to 1. At the same time, NMI interrupt is requested.
φ
TCNT H'FF H'00
OVF
Overflow signal
(internal signal)
Figure 13.4 Timing of OVF Setting