142PPC-120/140 User's ManualProgramming the Watchdog TimerTo program the watchdog timer, you must write a program which writesI/O port address 443 (hex). The output data is a time interval value. Thevalue range is from 01 (hex) to 3F (hex), and the related time interval isfrom 1 sec. to 63 sec.Data Time Interval01 1 sec.02 2 sec.03 3 sec.04 4 sec.• •• •• •3F 63 sec.After data entry, your program must refresh the watchdog timer byrewriting the I/O port 443 (hex) while simultaneously setting it. When youwant to disable the watchdog timer, your program should read I/O port443 (hex).
