Advantech SOM-4463 B2, User Manual

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SOM-4463 B2 User Manual 36
A.1 Programming the Watchdog Timer
Sample code for programming the watchdog timer function:
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Enter the extended function mode, interruptible double-write |
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MOV DX,2EH
MOV AL,87H
OUT DX,AL
OUT DX,AL
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Configured logical device 8, configuration register CRF6 |
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MOV DX,2EH
MOV AL,2BH
OUT DX,AL
MOV DX,2FH
IN AL,DX
AND AL.OEF; set bit 4 = 0 Pin 89 = WDTO
OUT DX,AL
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 the watchdog to activate or inactivate
OUT DX,AL
MOV DX,2FH
MOV AL,01H; 01: activate 00: inactivate
OUT DX,AL;
MOV DX,2EH
MOV AL,F5H; the setting counter unit is seconds
OUT DX,AL
MOV DX,2FH
MOV AL,00H
OUT DX,AL;
MOV DX,2EH
MOV AL,F6H
OUT DX,AL
MOV DX,2FH
MOV AL,05H; set to 5 seconds
OUT DX,AL
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