Protech Systems BA-2501, User Manual

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Appendix A Technical Summary
BA-2501 SERIES USER MANUAL
Page: A-15
Code example for watch dog timer
Enable watchdog timer and set 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
; -------------------------- Set timeout interval as 30 seconds ----------------------------
dec dx
mov al, 0F6h
out dx, al
inc dx
mov al, 1Eh
out dx, al
;------------------------------- Enable Watch PME--------------------------------------------
dec dx
mov al, 0FAh
out dx, al
inc dx
in al, dx
or al, 51h
out dx, al
;------------------- Set second as counting unit and start counting --------------------
dec dx
mov al, 0F5h
out dx, al
inc dx
in al, dx
and al, 0F7h
or al, 20h
out dx, al
;---------------------------- Exit the extended function mode ------------------------------
dec dx
mov al, 0AAh
out dx, al