Watch Dog Timer question

[lpcware]

Content originally posted in LPCWare by -0o- on Thu Aug 08 16:13:55 MST 2013
I have done some researches on watch dog timers
but i still would like to know how use it is
and in which type of applications will using a watch dog timer
be useful ??

what does it do basically ??

and also what is the phase locked loop ? PLL

[lpcware]

Content originally posted in LPCWare by embd02161991 on Mon Aug 12 23:12:19 MST 2013
Watchdog timers are very useful in case the system enters an undefined state. The watchdog timer helps in rebooting the system or restoring the previous state of the system before the crash.

[lpcware]

Content originally posted in LPCWare by TheFallGuy on Fri Aug 09 03:40:01 MST 2013
Watchdog: http://en.wikipedia.org/wiki/Watchdog_timer

It is useful in critical applications where your system must keep running, but where the software has crashed, hung or is taking 'too long'. If the watchdog is not 'fed' with a special 'feed sequence' every user-defined period, the watchdog will reset (reboot) your system.

PLL: http://en.wikipedia.org/wiki/PLL