A.1 watchdog timer working procedure – NEXCOM NEX 852VL2 User Manual
Page 58
The NEX852VL(2) features a watchdog timer that reset the CPU or generates an interrupt if the processor
stops operating for any reason. This feature ensures system reliability in industrial standalone or unmanned
environments.
A.1 Watchdog Timer Working Procedure
The Watchdog Timer (WDT) is a special hardware device that monitors the computer system during normal
operation. The WDT has a clock circuit that times down from a set number to zero. If a monitored item
occurs before the timer reaches zero, the WDT resets and counts down again. If for some reason the
monitored item doesn’t occur before the timer reaches zero, the WDT performs an action, such as a diag-
nostic operation (rebooting the computer) or generate an NMI.
You must enter timer values into the WDT Configuration Register (Write the control value to the Configura-
tion Port), and clear (read the Configuration Port).
Table A-1: Watchdog Timer Character and Function
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