Appendix a p rogramming the w atchdog timer – Advantech Industrial Mini-ITX Motherboard with DDR2/Dual GbE/PCI AIMB-221 User Manual
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AIMB-221 User Manual
Appendix A
P
rogramming
the
W
atchdog
Timer
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
; Enable watchdog timer to be strobed reset by keyboard
Mov
al,0f7h
Out
dx,al
Inc
dx
In
al,dx
Or al,40h
Out
dx,al
;-----------------------------------------------------------
Dec dx
; lock W83627HF
Mov
al,0aah
Out
dx,al
Generate a time-out signal without timer counting
;-----------------------------------------------------------
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