Nexcom PEAK 7220VL2G, User Manual

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Appendix: Watchdog Timer Setting
WDT Configuration port F2 Default at F2
Watch Dog Timer Disabled 1. Default at disabled
Enabled 2. Enabled for user’s programming
WDT Active Time 1 sec Default at 64 sec
2 sec
4 sec
8 sec
16 sec
32 sec
64 sec
128 sec
Table B-1 : Watchdog Timer Character and Function
1 Watchdog Timer Working Procedure
Watchdog Timer (WDT) is a special hardware device that monitors the computer
system during normal operation. WDT has a clock circuit that times down from a set
number to zero. If a monitored item occurs before the timer reaches zero, WDT resets
and counts down again. If for some reason the monitored item doesn’t occur before
the timer reaches zero, WDT performs an action, such as a diagnostic operation
(rebooting the computer).
You must enter timer values into WDT Configuration Register (Write the control value
to the Configuration Port), and clear WDT counter (read the Configuration Port).