新手，一个显存问题

assume cs:htcode
htcode segment
 star:
  mov ax,0b872h
  mov ds,ax
  mov bx,0
  mov cx,16
  mov al,41h
  go:
  mov ds:[bx],al
  add bx,1
  add al,1
  mov dl,2
  mov ds:[bx],dl

  loop go
  mov ax,4c00h
  int 21h
htcode ends
end star
为什么，显示的不是ABCDE蓝字
望大侠们指点

Assembly code

assume cs:htcode
htcode segment
 star:
        mov ax,0b872h
        mov es,ax
        
        mov di,0
        mov cx,16
        mov al,41h
  go:
        mov es:[di],al
        add di,1
        mov dl,2
        mov es:[di],dl
        add di,1
        add al,1

        loop go
        mov ax,4c00h
        int 21h
htcode ends
end star