hexout:   mov cx, 4
hoh:        rol ax, 4
            mov dx, ax
            and dl, 0Fh
            add dl, '0'
            cmp dl, '9'
            jng hona
             add dl, 'A'-'9'-1
hona:       mov bx, ax
            mov ah, 2
            int 21h
            mov ax, bx
            loop hoh
          ret