JS Automation Corp CPU-2616 PCI-104, Руководство пользователя

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5.6.1 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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