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PCA-6185 User’s Manual 88
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).