GETSTR MACRO STR
MOV AH,0AH
LEA DX,STR
INT 21h
ENDM

PRINTSTR MACRO STR
MOV AH,09H
LEA DX,STR
INT 21H
ENDM

DATA SEGMENT
        STR1 DB 80,80 DUP('$')
        STR2 DB 80,80 DUP('$')
        MSG1 DB 10,13,'ENTER THE STRING :$'
        MSG2 DB 10,13,'THE COPIED STRING IS :$'
DATA ENDS
CODE SEGMENT
        ASSUME CS:CODE,DS:DATA
        START: MOV AX,DATA
                 MOV DS,AX
        
                 PRINTSTR MSG1
                 GETSTR STR1
                 LEA SI,STR1+2
                 LEA DI,STR2+2
        
                 MOV CL,STR1+1 ;FOR STORING THE LENGTH OF THE STRING
                 MOV CH,00H
       LAB1:   MOV AL,DS:BYTE PTR[SI]
                    MOV DS:BYTE PTR[DI],AL
                    INC DI
                    INC SI  ;FOR GOING TO THE END OF THE STRING
                    LOOP LAB1
        
                   PRINTSTR MSG2
                   PRINTSTR STR2+2
              
                 MOV AX,4C00H
                 INT 21H
CODE ENDS
        END START

OUTPUT
***********
D:\tasm\tasm1>m11
ENTER THE STRING :ABC
THE COPIED STRING IS :ABC