.model tiny 
.code 
.startup 
	; org 100h

	mov  bx, 896 ; original value: 2000
        mov  ax, 34dch 
        mov  dx, 12h 
        div  bx 
        out  42h, al 
        mov  al, ah 
        out  42h, al 

        in   al, 61h 
        or   al, 03h 
        out  61h, al 

        mov  dx, 0fffh 
back: 
        mov  cx, 0ffffh 
same: 
        loop same 
        dec  dx 
        jnz  back 
        in   al, 61h 
        xor  al, 03h 
        out  61h, al 

	mov ax, 1  ; exit
	int 20h	   ; sys _exit	
 .exit

end