Advantech PCA-6185 User Manual

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PCA-6185 User’s Manual
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Appendix A  Programming the Watchdog 
Timer
A.1  Programming the Watchdog Timer
To program the watchdog timer, you must write a program which writes I/
O port address 444 (hex). The output data is a time interval value. The 
value range is from 01 (hex) to 3E (hex), and the related time interval is 
from 1 sec. to 62 sec.
Data Time Interval
01
1 sec.
02
2 sec.
03
3 sec.
04
4 sec.
3E
62 sec.
After data entry, your program must refresh the watchdog timer by rewrit-
ing the I/O port 444 (hex) while simultaneously setting it. When you want 
to disable the watchdog timer, your program should read I/O port 43 
(hex).