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CHAPTER 12 HARDWARE WATCHDOG TIMER
12.1
Overview of Hardware Watchdog Timer
The hardware watchdog timer serves as a counter used to prevent programs from
running out of control.
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Hardware Watchdog Timer Function
The hardware watchdog timer functions as a counter used to prevent programs from running out of control.
Once the hardware watchdog timer is activated, its counter needs to be cleared at specified intervals
regularly. A hardware 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 RC oscillator is the count clock for the hardware watchdog timer. Table 12.1-1 shows the
minimum and maximum frequency of RC oscillator.
The interval times of the hardware watchdog timer are shown in Table 12.1-2. If the counter of the
hardware watchdog timer is not cleared, a hardware watchdog reset is generated between the minimum
time and the maximum time. Clear the counter of the hardware watchdog timer within the minimum time.
For information about the minimum and maximum times of the hardware watchdog timer interval, refer to
"12.4 Explanation of Hardware Watchdog Timer Operations and Setup Procedure Example".
Table 12.1-1 Frequency of RC oscillator
Frequency
Min.
Typ.
Max.
RC oscillator
50kHz
100kHz
200kHz
Table 12.1-2 Interval Times of Hardware Watchdog Timer
Count clock
Interval time
Minimum time
Maximum time
RC oscillator
327.68 ms
(RC=200kHz)
2.62 s
(RC=50kHz
)
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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Страница 482: ...468 CHAPTER 25 LOW VOLTAGE DETECTION RESET CIRCUIT ...
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Страница 564: ...550 CHAPTER 29 EXAMPLE OF SERIAL PROGRAMMING CONNECTION ...
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Страница 599: ...585 Pin Function Index V2 LCD power supply driving pin 2 439 V3 LCD power supply driving pin 3 439 ...
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