NEXCOM NEX 732L2G - Manual (Page 63)

62 Appendix A NEX732L2G User Manual
The NEX732L series 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
WDT Configuration port F2 Default at F2
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
Watchdog Timer