Protech Systems PA-3222, User Manual

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Appendix B Technical Summary
PA-3222 SERIES USER MANUAL Page: B-11
Code example for watch dog timer
Enable the watchdog timer and set the timeout interval to 30 seconds.
; ------------------------- Enter to extended function mode -------------------------------
mov dx, 2eh
mov al, 87h
out dx, al
out dx, al
; ----------------------- Select Logical Device 7 of watchdog timer ---------------------
mov al, 07h
out dx, al
inc dx
mov al, 07h
out dx, al
;---------------------------------Enable Watch dog feature ------------------------------
mov al, 030h
out dx, al
inc dx
mov al, 01h
out dx, al
;------------------------------- Enable Watch PME--------------------------------------------
dec dx
mov al, 0FAh
out dx, al
inc dx
in al, dx
and al, 51h
out dx, al
;-------------------------- Set second as counting unit --------------------------------------
dec dx
mov al, 0F5h
out dx, al
inc dx