Advantech AIMB-221 manual Appendix a Programming the Watchdog Timer

Dec dx		; Set second as counting unit
Mov	al,0f5h
Out	dx,al
Inc	dx
In	al,dx
And al,not 08h
Out	dx,al
;-----------------------------------------------------------
Dec dx		; Set timeout interval as 10 seconds and start counting
Mov	al,0f6h
Out	dx,al
Inc	dx
Mov	al,10
Out	dx,al
;-----------------------------------------------------------
Dec dx		; lock W83627HF
Mov	al,0aah
Out	dx,al
Enable watchdog timer and set 5 minutes as the timeout interval
;-----------------------------------------------------------
Mov dx,2eh		; unlock W83627HF
Mov al,87h
Out dx,al
Out dx,al
;-----------------------------------------------------------
Mov al,07h		; Select registers of watchdog timer
Out	dx,al
Inc	dx
Mov	al,08h
Out	dx,al
;-----------------------------------------------------------
Dec dx		; Enable the function of watchdog timer
Mov	al,30h
Out	dx,al
Inc	dx
Mov	al,01h
Out	dx,al
;-----------------------------------------------------------
Dec dx		; Set minute as counting unit
Mov	al,0f5h
Out	dx, al
Inc	dx
In	al,dx
Or al, 08h
Out	dx,al

Appendix A Programming the Watchdog Timer

93 AIMB-221 User Manual