assume cs:code
code segment
start:
mov al, 8
out 70h, al
in al, 71h
mov ah,al
mov cl, 4
shr ah, cl
and al, 00001111b
add ah, 30h
add al, 30h
mov bx, 0b800h
mov es, bx
mov bl, 0ah
mov byte ptr es:[160*12+40*2], ah
mov byte ptr es:[160*12+40*2+1], bl
mov byte ptr es:[160*12+40*2+2], al
mov byte ptr es:[160*12+40*2+3], bl
mov ax, 4c00h
int 21h
code ends
end start