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CHAPTER 11 WATCHDOG TIMER
11.1
Overview of Watchdog Timer
The watchdog timer serves as a counter used to prevent programs from running out of
control.
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Watchdog Timer Function
The watchdog timer functions as a counter used to prevent programs from running out of control. Once the
watchdog timer is activated, its counter needs to be cleared at specified intervals regularly. A watchdog
reset is generated if the timer is not cleared within a certain amount of time due to a problem such as the
program entering an infinite loop.
The output of either the timebase timer or watch prescaler can be selected as the count clock for the
watchdog timer.
The interval times of the watchdog timer are shown in Table 11.1-1. If the counter of the watchdog timer is
not cleared, a watchdog reset is generated between the minimum time and the maximum time. Clear the
counter of the watchdog timer within the minimum time.
*: WDTC:CS1, 0: Count clock switch bit of watchdog timer control register
For information about the minimum and maximum times of the watchdog timer interval,
refer to "11.4 Explanation of Watchdog Timer Operations and Setup Procedure Example".
Table 11.1-1 Interval Times of Watchdog Timer
Count clock type
Count clock switch bit
(WDTC:CS1, 0)*
Interval time
Minimum time
Maximum time
Timebase timer output
(main clock = 4MHz)
00
524 ms
1.05 s
01
262 ms
524 ms
Watch prescaler output
(Subclock = 32.768kHz)
10
500 ms
1.00 s
11
250 ms
500 ms
Содержание F2 MC-8FX Family
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Страница 35: ...21 CHAPTER 2 HANDLING DEVICES This chapter gives notes on using 2 1 Device Handling Precautions ...
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Страница 39: ...25 CHAPTER 3 MEMORY SPACE This chapter describes memory space 3 1 Memory Space 3 2 Memory Map ...
Страница 43: ...29 CHAPTER 4 MEMORY ACCESS MODE This chapter describes the memory access mode 4 1 Memory Access Mode ...
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Страница 105: ...91 CHAPTER 8 INTERRUPTS This chapter explains the interrupts 8 1 Interrupts ...
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