After data entry, your program must refresh the watchdog timer by rewriting 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:
10REM Watchdog timer example program
20OUT &H443, data REM Start and restart the watchdog
30GOSUB 1000 REM Your application task #1,
40OUT &H443, data REM Reset the timer
50GOSUB 2000 REM Your application task #2,
60OUT &H043, data REM Reset the timer
70X=INP (&H043) REM, Disable the watchdog timer
80END
1000 | REM Subroutine #1, your application task |
• | • |
• | • |
• | • |
1070 | RETURN |
2000 | REM Subroutine #2, your application task |
• | • |
• | • |
• | • |
2090 | RETURN |
Appendix A Programming the Watchdog Timer | 45 |
