WIN Enterprises PL-10390, Руководство пользователя

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Appendix A: Programming the Watchdog Timer
The PL-10390 [MB-90420 board] provides a watchdog timer that resets the CPU
or enables LAN bypass mode. This function ensures greater system reliability in
industrial standalone and unmanned environments.
In order to enable the watchdog timer, you have to output the value of the
watchdog timer interval to the controller. The value range is from 01H to FFH,
and the related time watchdog timer interval is 1 sec to 255 sec.
Data Timer interval
00 Disabled
01 1 sec
02 2 sec
* *
* *
FF 255sec
If you want to disable the watchdog timer, just set the timer interval value to
00H.
After setting the timer interval value, the watchdog timer begins to countdown.
You have to refresh the watchdog timer, so that the watchdog timer will return to
its initial value; otherwise, your system will reset after a timeout. The following
program shows how to set the watchdog timer:
ASSEMBLY LANGUAGE DOS DEBUG
Program 1: Initializing the watchdog controller