Advantech AIMB-330F, User Manual

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AIMB-330F User’s Manual 82
Appendix A Programming the Watchdog
Timer
A.1 Programming the watchdog timer
The following example shows how you might program the watchdog
timer in assembly:
Watch Dog:
;-----------------------------------------------------------------------------------
; Enter the extended function mode ,interruptible double-write |
;-----------------------------------------------------------------------------------
MOV DX,2EH
MOV AL,87H
OUT DX,AL
OUT DX,AL
;-----------------------------------------------------------------------------
; Configurate logical device 8, configuration register CRF6 |
;-----------------------------------------------------------------------------
MOV DX,2EH
MOV AL,07H ; point to Logical Device Number Reg.
OUT DX,AL
MOV DX,2FH
MOV AL,08H ; select logical device 8
OUT DX,AL
;
MOV DX,2EH
MOV AL,30H ;Set watch dog activate or inactivate
OUT DX,AL
MOV DX,2FH
MOV AL,01H ; 01:activate 00:inactivate
OUT DX,AL
;