Advantech UNO-3072A, User Manual

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UNO-3072A/3074A User Manual 72
Appendix B Programming the Watchdog
Timer
B.1
Below is a sample of programming code for controlling the Watchdog
Timer function.
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Enter the extended function mode, interruptible double-write |
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MOV DX,4EH
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,4EH
MOV AL,2BH
OUT DX,AL
MOV DX,4FH
IN AL,DX
AND AL.OEFH;Setbit 4=0 Pin 89=WDTO
OUT DX,AL
MOV DX,4EH
MOV AL,07H; point to Logical Device Number Reg.
OUT DX,AL
MOV DX,4FH
MOV AL,08H; select logical device 8
OUT DX,AL;
MOV DX,4EH
MOV AL,30H;Set watch dog activate or inactivate