Programming The Watchdog Timer - Advantech PCM-5862E User Manual

Programming the Watchdog Timer

In order to program the watchdog timer, you must write a program
which writes I/O port address 443 (hex). The output data is a value of
time interval. The value range is from 01(hex) to 3F(hex), and the
related time interval is 1 sec. to 63 sec.
Data
01
02
03
04
3F
After data entry, your program must refresh the watchdog timer by
rewriting the I/O port 443 (hex) while simultaneously setting it. When
you want to disable the watchdog timer, your program should read I/O
port 443 (hex).
The following example shows how you might program the
watchdog timer in BASIC:
10 REM Watchdog timer example program
20 OUT &H443, data
30 GOSUB 1000
40 OUT &H443, data
50 GOSUB 2000
60 OUT &H443, data
70 X=INP (&H443)
80 END
1000 REM
.
.
.
1070 RETURN
2000 REM
.
.
.
2090 RETURN
PCM-5862E/EL User's Manual
80
Time Interval
1 sec.
2 sec.
3 sec.
4 sec.
.
.
.
63 sec.
REM Your application task #1
REM Your application task #2
REM Disable the watchdog timer
Subroutine #1, you application task
Subroutine #2, you application task
REM Start and restart the watchdog
REM Reset the timer
REM Reset the timer