Watchdog Timer - Boser HS-2621 Manual

3.17 Watchdog Timer

A user can set a value of Watchdog Timer in his software to reboot their
hardware system. It is forced to reboot once user's software fails to
reset the Watchdog Timer before the counter of Watchdog Timer
meets user's setting value. This function, Watchdog Timer, prevents
user's software from crashing.
3.17.1 Assembly Language Code
W83627EHG
WDT Assembly sample code:
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Extended function mode
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MOV DX,2EH
MOV AL,87H
OUT DX,AL
OUT DX,AL
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Configure logical device 8
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MOV DX,2EH
MOV AL,07H
OUT DX,AL
MOV DX,2FH
MOV AL,08H
OUT DX,AL
MOV DX,2EH ; Define Reset
MOV AL,2DH
OUT DX,AL
MOV DX,2FH
MOV AL,21H
OUT DX,AL
MOV DX,2EH
MOV AL,30H ; Enable WDT
OUT DX,AL
MOV DX,2FH
MOV AL,01H
OUT DX,AL
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Configure time mode
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MOV DX,2EH
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