User’s Manual U13850EJ4V0UM
236
CHAPTER 9 WATCHDOG TIMER
9.1 Functions
The watchdog timer has the following functions.
• Watchdog timer
• Interval timer
• Selecting the oscillation stabilization time
Caution Use the watchdog timer mode register (WDTM) to select the watchdog timer mode or the interval
timer mode.
Figure 9-1. Block Diagram of Watchdog Timer
Internal bus
OSTS0
OSTS1
OSTS2
OSTS
WDTM4
RUN
WDTM
WDCS
WDCS0
WDCS1
WDCS2
3
INTWDT
Note 1
INTWDTM
Note 2
3
Output
controller
Prescaler
Selector
f
XX
/2
22
f
XX
/2
10
f
XX
/2
20
f
XX
/2
19
f
XX
/2
18
f
XX
/2
17
f
XX
/2
16
f
XX
/2
15
f
XX
/2
14
RUN
Clear
OSC
Selector
Notes 1.
In watchdog timer mode
2.
In interval timer mode
Remark
f
XX
: Main clock frequency