帮忙看一下这个代码哪错了？多谢了

帮忙看一下这个代码哪错了？？谢谢了
assume cs:code,ds:data,ss:stack
stack segment
stack ends

data segment
mess1 db 'this is a message ...',0ah,0dh, '$'
mess2 db 'this is another message ...',0ah,0dh,'$'
data ends

code segment
start:
mov ax,data
mov ds,ax

lea dx,mess1
call show_message

lea dx,mess2
call show_message

sh_me mess1
sh_me mess2

mov ah,0ah
int 21h

mov ax,4c00h
int 21h

show_message proc
mov ah,09h
int 21h
ret
show_message endp

sh_me macro str
local isdecm
lea dx, str
mov ah,09h
int 21h
endm
code ends
end start


------解决方案--------------------
宏在使用之前先要定义。