Interval Timer Operation - Renesas Hitachi H8S/2194 Series Hardware Manual

18.3.2

Interval Timer Operation

To use the WDT as an interval timer, clear the WT/
1. An interval timer interrupt (WOVI) is generated each time WTCNT overflows, provided that
the WDT is operating as an interval timer, as shown in figure 18.4. This function can be used to
generate interrupt requests at regular intervals.
WTCNT value
H'FF
H'00
WT/IT=0
TME=1
WOVI : Interval timer interrupt request generation
Rev. 2.0, 11/00, page 400 of 1037
Overflow
WOVI
Figure 18.4 Operation in Interval Timer Mode
,7
bit in WTCSR to 0 and set the TME bit to
Overflow Overflow
WOVI WOVI
Overflow
Time
WOVI