HD6432633 Datasheet, PDF (739/1453 Pages) Renesas Technology Corp – Series of Microcomputers (MCUs: microcomputer units)

TCNT count
H'FF
Overflow
H'00
WT/IT=1
TME=1
H'00 written
to TCNT
WDTOVF signal
WOVF=1
WDTOVF and
internal reset are
generated
Time
WT/IT=1 H'00 written
TME=1 to TCNT
Internal reset signal*¹
132 states*²
Legend
WT/IT : Timer mode select bit
TME : Timer enable bit
518 states
Notes: *1 The internal reset signal is generated only if the RSTE bit is set to 1.
*2 130 states when the RSTE bit is cleared to 0.
Figure 15-4 (a) WDT0 Watchdog Timer Operation
TCNT value
H'FF
Overflow
H'00
WT/IT= 1 Write H'00
TME= 1 to TCNT
Time
WOVF= 1*
Occurrence
of internal reset
WT/IT= 1 Write H'00
TME= 1 to TCNT
Internal
reset signal
515/516 states
Legend
WT/IT : Timer Mode Select bit
TME : Timer Enable bit
Note: * The WOVF bit is set to 1 and then cleared to 0 by an internal reset.
Figure 15-4 (b) WDT1 Operation in Watchdog Timer Mode
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