HD6432670 Hitachi, HD6432670 Datasheet - Page 673

• Manufacturer Part Number: HD6432670
• Description: (HD64F267x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

14.4.2
To use the WDT as an interval timer, set the WT/
When the WDT is used as an interval timer, an interval timer interrupt (WOVI) is generated each
time the TCNT overflows. Therefore, an interrupt can be generated at intervals.
When the TCNT overflows in interval timer mode, an interval timer interrupt (WOVI) is requested
at the same time the OVF bit in the TCSR is set to 1.
Internal reset signal *
Legend
WT/
TME
Notes: 1. If TCNT overflows when the RSTE bit is set to 1, an internal reset signal is generated.
: Timer mode select bit
: Timer enable bit
2. 130 states when the RSTE bit is cleared to 0.
Interval Timer Mode
signal
H'FF
H'00
TCNT count
WT/ =1
TME=1
1
Figure 14.2 Operation in Watchdog Timer Mode
H'00 written
to TCNT
internal reset are
generated
bit to 0 and TME bit in TCSR to 1.
Overflow
132 states *
WOVF=1
518 states
and
Rev. 2.0, 04/02, page 627 of 906
2
WT/ =1
TME=1
H'00 written
to TCNT
Time