76 PCA-6148/6148L User's Manual
Programming the watchdog timer
If you decide to program the watchdog timer, you must write data
to I/O port 443 (hex). The output data is a value timer. You can
write from 01 (hex) to 3E (hex), and the related timer is 1 sec. to
63 sec.
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 043 (hex).
The following procedure is a program for the watchdog timer:
Step 1
Out 443h data REM Start and reset the watchdog
timer.
Step 2
Your application program task #1
Step 3
Out 443h data REM Reset the timer
Step 4
Your application program task #2
Step 5
Out 443h data REM Reset the timer
Step 6
in 043h, REM Disable the watchdog timer
Data Values
01
1 sec.
02
2 sec.
03
3 sec.
04
4 sec.
.
.
.
3F
63 sec.
Summary of Contents for PCA-6148
Page 1: ...PCA 6148 6148L Full size 486 All in one CPU Card with Flash RAM ROM disk ...
Page 26: ...18 PCA 6148 6148L User s Manual ...
Page 38: ...30 PCA 6148 6148L User s Manual ...
Page 72: ...64 PCA 6148 6148L User s Manual ...
Page 73: ...Appendix A Flash RAM ROM disk 65 A Flash RAM ROM Solid State Disk A P P E N D I X ...
Page 87: ...Appendix C Upgrading 79 PC 104 module dimensions mm ...
Page 90: ...82 PCA 6148 6148L User s Manual ...
Page 100: ...92 PCA 6148 6148L User s Manual ...
Page 108: ...100 PCA 6148 6148L User s Manual ...
