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TITLE   beep.asm Beeps the speaker

;========================================================================

CSEG    SEGMENT
        ASSUME CS:CSEG,DS:CSEG
        ORG 100h

start:  jmp begin


beep    PROC NEAR

;        0A97h = 440 Hz

        mov al,0B6h
        out 43h,al

        mov al,97h
        out 42h,al                 ;Load divisor, LSB then MSB
        mov al,0Ah
        out 42h,al

        in al,61h
        push ax

        or al,03h

        out 61h,al                 ;S„tt p† h”gtalare


        mov cx,-2
delay1:        
        push cx
        mov cx,20h
delay2:        
        loop delay2
        pop cx
        loop delay1

        pop ax
        out 61h,al

        ret

beep   ENDP


begin:
        call beep
        ret                             ; -> back to DOS
 
CSEG    ENDS
END     start
.

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