Interval Timer Operation - Hitachi H8S/2199 Hardware Manual

17.3.2

Interval Timer Operation

To use the WDT as an interval timer, clear the WT/,7 bit in WTCSR to 0 and set the TME bit to
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 17.4. 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. 1.0, 02/00, page 356 of 1141
Overflow
WOVI
Figure 17.4 Operation in Interval Timer Mode
Overflow Overflow
WOVI WOVI
Overflow
Time
WOVI