Printing inputted string in assembly language-CodePudding

I wanna print what the user inputted first. However, it displays the converted uppercase already before the result.

Here's my code:

  org 100h


BEGIN:
          LEA DX, DASH1          
          MOV AH, 9
          INT 21H
          
          LEA DX,LOWERCASE
          MOV AH,09H
          INT 21H

          LEA SI,STR1
          MOV AH,01H
              
              
READ:
          INT 21H
          MOV BL,AL 

          CMP AL,0DH
          JE  DISPLAY

          XOR AL,20H
          MOV [SI],AL
          INC SI

          JMP READ        
          

DISPLAY:               
          MOV AL,"$"
          MOV [SI],AL                    

          LEA DX,UPPERCASE
          MOV AH,09H
          INT 21H   
                 
          LEA DX, STR1
          MOV AH, 09H
          INT 21H 
          
          MOV DL, BH  ; space
          MOV AH, 02H
          INT 21H               
          
          LEA DX, UPPERCASE_          
          MOV AH, 9
          INT 21H
          
          LEA DX,STR1
          MOV AH,09H
          INT 21H 
          
          LEA DX, DASH2          
          MOV AH, 9
          INT 21H

          MOV AH,4CH
          INT 21H
         
  ret
   
    LOWERCASE  DB 0DH,0AH,0AH, "   Input a 5-letter string: $"
    UPPERCASE DB  0DH,0AH, "   The uppercase equivalent of $"
    UPPERCASE_ DB "is $"   
    DASH1 DB 0AH,0DH, " ================================================================= $"  
    DASH2 DB 0AH,0AH,0DH, " ================================================================= $"
    STR1 DB 255 DUP(?)

Output:

Input a 5-letter string: asdfg

The uppercase equivalent of ASDFG is ASDFG

                             ^ i want this part to print as `asdfg`

making it The uppercase equivalent of asdfg is ASDFG

P.S. also, how do I make the string limited to 5 only? Its because the string a user can input can exceed more than 5. Any tips?

==============================================================================

CodePudding user response：

You are displaying strings UPPERCASE, STR1, UPPERCASE_,STR1, respectively, no wonder that STR1 remains the same. You need to reserve one more string STRorig where you should store the obtained character before its case is changed.
You can use DI to address STRorig and then perform STOSB for saving original AL to ES:DI and incrementing DI.

When you want to limit the size of input string, compare SI with STR1 5 and if it's above, act as if AL was equal to 0DH.