mov al,13h
int 10h
lds cx,[bx]
mov ax,di
xor dx,dx
mov bx,0C740h
add [bx+di+0C840h],bh
add dx,cx
and ax,dx
shr ax,cl
xor [di],al
inc di
jnz 000000006h
inc cx
jmp 000000006h
nop