User`s manual

Chapter 4 System Resources
Watch Dog Timer Setting
Software Code
SIO_IDX equ 4EH
SIO_DTAequ 4FH
Timer equ 10; reset after 10 seconds
1. Enter configuration mode
Mov dx, SIO_IDX
mov al, 87h
out dx, al
out dx, al
2. Set to LDN 07
Mov dx, SIO_IDX
mov al, 07h out dx, al
mov dx, SIO_DTA
mov al, 07h
out dx, al
3. Set WatchDog Timer
Mov dx, SIO_IDX
mov al, 0f6h
out dx, al
mov dx, SIO_DTA
mov al, Timer
out dx, al
4. Exit configuration mode
Mov dx, SIO_IDX
mov al, 0AAh
out dx, al
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