Renesas 7700 FAMILY User Manual page 247

WATCHDOG TIMER
9.1 Block description
This chapter describes Watchdog timer.
Watchdog timer has the following functions:
Detection of a program runaway.
Measurement of a certain time when oscillation starts owing to terminating Stop mode.
(Refer to "Chapter 10. STOP MODE.")
9.1 Block description
Figure 9.1.1 shows the block diagram of the watchdog timer.
f /f
2 4
Hold request
Writing to watchdog timer
register (address 60
RESET
STP instruction
Fig. 9.1.1 Block diagram of watchdog timer
9–2
Wf
32
1/16
Wf /Wf
512
1/16
)
16
2V
cc
detection
circuit
Q
S
R
7751 Group User's Manual
Watchdog timer
frequency select bit
/Wf
64
Watchdog timer
1024
Watchdog timer
interrupt request
"FFF "
16
is set.