Aaeon SBC-357, Руководство пользователя

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Appendix A Watchdog Timer Demo Program 65
Read_From_Chip PROC
;;Input: al - Index#
;;Output al - Data
cli
Open_Chip
out
22h,al
IO_Delay
in
al,23h
IO_Delay
Close_chip
sti
ret
ENDP
Watchdog_Timer_Program:
Open_Chip
mov
al,37h
call Read_From_Chip
mov bl,al ;;save register data
and al,10111111b ;;set bit6=0 to disable
timer
mov ah,al
mov al,37h
call Write_To_Chip
mov ah,33 ;;1 msec=33x30.5u sec
mov al,39h
call Write_To_Chip
mov ax,003ah
call Write_To_Chip
mov ax,003bh
call Write_To_Chip
mov al,bl
mov al,38h
call Read_From_Chip
and al,00001111B
or al,11010000b ;;set time-out event aas
system reset
mov ah,al
mov al,38h
call Write_to_Chip
mov al,bl
or al,01000000b ;;set bit6 = 1 to enable
timer
mov ah,al
mov al,37h
call Write_To_Chip