谁帮我找一下这个程序的错误地方啊
在DATA中存放有一字符串，编写子程序实况将其中的小写字母改为大写字母。data segment
DATA db '1234abhfgELF78'
count euq $-DATA
data ends
code segment
aussme cs:code, ds:data
main proc far
push ds
mov ax,00h
push ax
mov ax,data
mov ds,ax
mov SI,0
mov cx,count
h1:mov al,DATA[SI]
call fh
sub al,20h
mov DATA[SI],al
inc SI
loop h1
ret
main endp
fh proc near
push ax
push cx
push SI
jb h2
mov al,DATA[SI]
pop SI
pop cx
pop ax
h2: ret
fh endp
code ends
end main
