FabiaTech Corporation
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Watchdog Timer Setting
The watchdog timer is a circuit that may be used from your program software to
detect system crashes or hang-ups. LED on the Front side is the watchdog timer
indicator. Whenever the watchdog timer is enabled, the LED will blink to indicate
that the timer is counting. The watchdog timer is automatically disabled after reset.
Once you have enabled the watchdog timer, your program must trigger the
watchdog timer every time before it times out. After you trigger the watchdog
timer, it will be set to non-zero value to watchdog counter and start to count down
again. If your program fails to trigger the watchdog timer before time-out, it will
generate a reset pulse to reset the system.
The factor of the watchdog timer time-out constant is approximately 1 second.
The period for the watchdog timer time-out is between 1 to FF timer factors.
If you want to reset your system when watchdog times out, the following table
listed the relation of timer factors between time-out periods.
Time Factor
Time-Out Period
(Seconds)
Time-Out Period
(Minutes)
1
1
1
2 2
2
3 3
3
4 4
4
5 5
5
“ “
“
“ “
“
“ “
“
FF FF
FF
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