从键盘输入字符串,如是 小写字母,则转为大写字母输出。如是大写字母,原样输出。并约定,键入复位键[ESC]中止输入。例:输入: deddeDEDG        按复位键[ESC]     输出:deddededg
data segment
string db 10 dup(?)
str db 10 dup(?)
data ends
code segment
assume cs:code,ds:data
main proc far
       mov ax,data
       mov ds,ax
       mov cx,10
       lea di,str
       lea si,string
    get:   mov ah,01h
int 21h
cmp al,1bh
jz done
mov byte ptr[si],al
inc si
loop get
      done:lea si,string 
 again:mov al,[si]
       cmp al,61h
       jae next
       mov byte ptr[di],al
      jmp next1
 next:
      sub al,20h
      mov byte ptr[di],al
 next1:inc si
       inc di
       loop again
    lea di,str
       mov ah,02h
       get1:mov dl,[di]
    int 21h
    inc di
        loop get1
    call nextline
       ret
     main endp
nextline proc near
mov dl ,0dh
mov ah,02h
int 21h
mov dl,0ah
mov ah,02h
int 21h
ret
nextline endp
code ends
end main



 
											





 
	    

 
	