I'm trying to add a watchdog on an Arduino Nano, for my code, and I'm following exactly code in [this manual][1], but after the amount of time for not resetting the watchdog- it resets but does not reboot.

At last paragraph- it says that :"

> However, I could not find something similar in Optiboot bootloader (If
> I'm wrong, correct me please!), used by Arduino UNO and other new
> boards. It seems that they sacrificed this check for size. So, it is
> possible that watchdog timer will be enabled after reset, so -  if you
> set it's value too low, your board may never come out of bootloader
> stage. So, to be always on the safe side, set watchdog to longer
> periods (2S and more).

So I've tried for 8s, but still same result.

What is wrong ?


  [1]: https://tushev.org/articles/arduino/5/arduino-and-watchdog-timer