WIN Enterprises MB-73200, Руководство пользователя

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Appendix A: Programming the Watchdog Timer
The MB-73200 provides a watchdog timer that resets the CPU or generates an
interrupt if processing comes to a stop. This function ensures greater system reliability
in industrial stand-alone 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 255 sec
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 count down. 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 time-out. The following program shows
how to set the watchdog timer: