پروژه كامل تبديل حروف بزرگ به حرف كوچيك وبرعكس

کد:
Stack    segment          stack 
  Db     100h   dup (?) 
stack    ends  
Data     segment 
strlist label byte 
Max     db     80 
Len     db  ? 
Data2   db 80 dup(?) 
Msg1    db "enter number and  digit" 
data3    db 80 dup(?) 
Data    ends 
Code    segment 
        Assume    cs:code,ds:data,ss:stack,es:data 
Org     100h    
mov     ax,data  
mov     ds,ax 
lea     dx,msg1 
Mov     ah,09 

Int     21h  
lea     ax,data3 
mov     si,ax 
Lea     di,data2 
lea      dx,strlist 
mov     ah,0ah 
int     21h    
Mov     cl ,len  
Back1:  mov al,[di] 
Cmp     al ,"A" 
Jb      over 
Cmp     al,"z"  
Ja      over 
Xor     al,00100000b 
Over:   mov [si],al 
Inc     si  
Inc     di 
Loop    back1 
lea     dx,data3 
mov     ah,09 
int      21h 
Mov     ah,4ch 
Int     21h 
Code    ends 
End