Assembly Code to Concatenate two Strings

Assembly Code to Concatenate two Strings

DATA SEGMENT
    STR1 DB "HELLO$"
    STR2 DB " INDIA$"
    STR DB ?
    TMP DW ?
DATA ENDS                        

CODE SEGMENT                
    ASSUME CS:CODE, DS:DATA
    ;SET LOOP COUNTER
    MOV CX, 5       
    ;ADDRESS OF STR1
    LEA BX, STR1   
    ;ADDRESS OF STR
    LEA AX, STR   
   
    AGAIN1:        
    ;PICK CHARACTER FROM BX(STR1)   
    MOV DL, [BX]   
    ;LOAD ADDRESS STR
    XCHG BX, AX      
    ;LOAD CHARACTER AT BX(STR)
    MOV [BX], DL             
    ;LOAD ADDRESS STR1
    XCHG AX, BX      
    ;INCREMENT STR1 ADDRESS
    INC BX               
    ;INCREMENT STR ADDRESS
    INC AX                             
    LOOP AGAIN1    
          
    ;ADDRESS OF STR1
    LEA BX, STR2  
    MOV CX, 6
   
    AGAIN2:        
    ;PICK CHARACTER FROM BX(STR21)   
    MOV DL, [BX]   
    ;LOAD ADDRESS STR
    XCHG BX, AX      
    ;LOAD CHARACTER AT BX(STR)
    MOV [BX], DL             
    ;LOAD ADDRESS STR2
    XCHG AX, BX      
    ;INCREMENT STR2 ADDRESS
    INC BX               
    ;INCREMENT STR ADDRESS
    INC AX                             
    LOOP AGAIN2
          
    ;LOAD ADDRESS OF STR                      
    XCHG BX, AX         
    ;END STR       
    MOV [BX], "!"
    INC BX
    MOV [BX], "$"     
   
    ;PRINT STR         
    MOV DX, OFFSET STR                      
    MOV AH, 09H
    INT 21H

CODE ENDS