Notes on using watchdog in embedded software development

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Notes on using watchdog in embedded software development [Copy link]

 

1. Set an appropriate count value: According to the real-time requirements of the system and the running time of the program, the count value of the watchdog needs to be set reasonably. If the count value is set too small, it may trigger a reset too early; if it is set too large, program abnormalities may not be detected in time. Usually, it needs to be adjusted according to the specific application scenario and system requirements.

2. Feeding interval: In order to avoid being reset, the watchdog needs to be fed periodically before the watchdog count value reaches the threshold. The feeding interval should be short enough, but not too frequent to avoid adding extra burden to the system. It is generally recommended to feed the watchdog between half and two-thirds of the count value.

3. Handling abnormal situations: If the program is abnormal or enters an infinite loop or other unresponsive state, it will not be able to feed the dog in time and will eventually trigger a reset. In order to ensure the stability of the program, it is necessary to handle various possible abnormal situations in the code to avoid situations where the program cannot run normally.

4. Ensure the reliability of feeding the dog: To ensure the punctuality and reliability of feeding the dog, you can use a hardware timer or a software timer to feed the dog regularly. The hardware timer can provide higher accuracy and stability, but in some systems there may be no hardware timer available, in which case it can be achieved through a software timer.

lkh747566933

A good summary of the precautions for using watchdogs in embedded software development

秦天qintian0303

We really need to consider the application of watchdogs. They were rarely used before.