FabiaTech Fanless FX5613, Руководство пользователя

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FabIATech Corporation
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Watchdog Timer Trigger
After you enable the watchdog timer, your program must write the same factor as
enabling to the watchdog register at least once every time-out period to its previous
setting. You can change the time-out period by writing another timer factor to the
watchdog register at any time, and you must trigger the watchdog before the new
time-out period in next trigger.
;--------------------------------------------------------------------------------------------------
;Set Watch Dog timer to 20 second used base address 0x300~0x301:
;--------------------------------------------------------------------------------------------------
MOV AX,03H ;Select unit to one second and clear time out status
MOV DX,300H
OUT DX,AX
MOV AX,14H
;Set timer to 20 second and enable time
MOV DX,301H
OUT DX,AX
OUT DX,AX
Watchdog Timer Disabled
To disable the watchdog timer, simply write a 00H to the watchdog register.
;------------------------------------------------------------------------------------------
; Enter the extended function mode, interruptible double-write
;------------------------------------------------------------------------------------------
Mov dx, 4eh ; Enter to extended function mode
Mov al, 77h
Out dx,al
Out dx,al
Mov al,07h ; Select register index 0x07
Out dx,al
;--------------------------------------------------------------------------------------------------------------------------
; Logical device 8, configuration register, CR30 Bit 0, Disable Watchdog Timer Device
;--------------------------------------------------------------------------------------------------------------------------
Mov dx,4fh ; Select LDN 8
Mov al,08h
Out dx,al
Mov dX,4eh
Mov al,30h ; Select LDN 8 register index 0x30
Out dx,al
Mov dx,4fh
Mov al,00h ; Disable Watch Dog Timer Device
Out dx,al
;------------------------------------------
; Exit extended function mode
;------------------------------------------
Mov dx,4eh
Mov al,0aah
Out dx,al