Peak Peak 632A, User Manual

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PEAK 632A Series User Guide
Watch Dog Timer A1-5
2. Select the time-out intervals of WDT (decide the values of D2, D1, D0 in F2 )
Example: D2~D0 = 0, the time-out interval will be 64 sec.
AND al, 11111000b ; Setting the time-out interval as 64 sec.
3. Enable or Disable the WDT ( decide D3 value in F2)
i.e. D3=0, Disable the WDT
AND al, 11110111b ; Disable the WDT
i.e. D3=1, Enable the WDT
OR al, 00001000b ; Enable the WDT
After finishing the above setting, you must be output for the Control Register value to the
WDT Configuration Port. Then WDT will start according to the above setting.
MOV dx, F2h ; Setting WDT Configuration Port
OUT dx, al ; Output the Control Register Value
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You should build in a mechanism in the program to continue to read the WDT
Configuration Port for clearing WDT before the time out.