SBC comm AMD SBC-770 - Manual (Page 110)

Appendix A Programming the Watchdog Timer 99
Demo program
outportb(0x444, 0): // set time-out event to reset-system
outportb(0x443x 10); // set time-out interval to 10 seconds
customer_job(); // execute your job here, be sure your
job will finished within 10 seconds
outportb(0x443, 0); // refresh watchdog timer, otherwise
the system will reset after time-out
outputb(0x443, 20); // set time-out interval to 20 seconds
another_job(); // another job finished in 20 seconds
outportb(0x443, 0) // disable watchdog timer
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