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Preliminary User’s Manual U16035EJ1V0UM
CHAPTER 9 WATCHDOG TIMER
9.1 Functions of Watchdog Timer
The watchdog timer has the following functions.
• Watchdog timer
• Interval timer
• Oscillation stabilization time selection
Caution
Select the watchdog timer mode or the interval timer mode with the watchdog timer mode
register (WDTM) (The watchdog timer and the interval timer cannot be used simultaneously).
Figure 9-1 shows a block diagram of the watchdog timer.
Figure 9-1. Block Diagram of Watchdog Timer
f
X
/2
8
RUN
Clock
input
controller
INTWDT
RESET
WDT mode signal
3
OSTS2 OSTS1 OSTS0
WDCS2 WDCS1 WDCS0
RUN WDTM4
Internal bus
Divider
Divided
clock
selection
circuit
Output
controller
Division mode
selection circuit
WDTM3
Oscillation stabilization
time select register
(OSTS)
Watchdog timer
clock select
register (WDCS)
Watchdog timer
mode register
(WDTM)
f
X
