How to use the Watchdog Timer

Autonomous Machines Jetson & Embedded Systems Jetson AGX Xavier
1

Hi,

I see that Watchdog is supported as a Linux Driver, is there any documentation that describes this API and other details?

https://docs.nvidia.com/jetson/l4t/index.html#page/Tegra%20Linux%20Driver%20Package%20Development%20Guide/software_features_jetson_xavier.html#wwpID0E0RB0HA

Best Regards,
UNA

3

Hi,
Tegra Watchdog is enabled by default. For further functions, please refer to
How To Enable PMIC-WDT
Enabling WDT_RESET_OUT_N Pin for Watchdog Timeout

4

Hi DaneLLL,

Thank you for your reply.

I have already checked the links you mentioned.
I would like to know what Watchdog users can use independently and how to use it.

Best Regards,
UNA

5

The watchdog timer is more or less standard across Ubuntu (it shouldn’t matter if it is the Tegra implementation or a desktop PC implementation), so documentation on the web for things like examples should work for you. The general theme is there is a timer running, and something has to periodically reset the timer via a watchdog file in “/dev”. If the thing resetting the timer fails, then the system timer reboots instead of resetting. The biggest difference across examples will be what it is which triggers the reset, which is not all that important for understanding the watchdog timer. It is possible you will run into a difference for PC versus Jetson, but for the most part there won’t be a difference.

There are a lot of tutorials on the internet, and some of the details about what can be monitored will differ, but just browse through any of these:
https://www.google.com/search?q=ubuntu+%22watchdog+timer%22+tutorial&ei=3R5SYZfOFNXU-wTAlZiAAQ&oq=ubuntu+%22watchdog+timer%22+tutorial&gs_lcp=Cgdnd3Mtd2l6EAMyBQghEKsCMgUIIRCrAjoHCAAQRxCwAzoECAAQHjoGCAAQFhAeOgUIIRCgAToHCCEQChCgAUoECEEYAFDe-BdYyLwYYNG-GGgBcAJ4AIABaYgBhAySAQQxOS4ymAEAoAEByAEIwAEB&sclient=gws-wiz&ved=0ahUKEwjXsNP79J_zAhVV6p4KHcAKBhAQ4dUDCA4&uact=5