11.3.2
Interval Timer Mode
Interval timer operation begins when the WT/IT bit is cleared to 0 and the TME bit is set to 1.
In interval timer mode, an WOVF request is generated each time the timer count overflows. This
function can be used to generate WOVF requests at regular intervals. See figure 11.4.
H'FF
TCNT count
H'00
Time t
WT/IT = 0 WOVF
TME = 1 request
WOVF
request
WOVF
request
WOVF
request
WOVF
request
Figure 11.4 Operation in Interval Timer Mode
Setting the Overflow Flag
11.3.3
The OVF bit is set to 1 when the timer count overflows. Simultaneously, the WDT module
requests an internal reset, NMI, or WOVF interrupt. The timing is shown in figure 11.5.
ø
H'FF H'00
TCNT
Internal overflow
signal
OVF
Figure 11.5 Setting the OVF Bit
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RENESAS [ RENESAS TECHNOLOGY CORP ]
