reverse_string.asm

.model stack
.stack 100H
.data

MSG1 DB 13,10,"enter string : $"
MSG2 DB 13,10,"reverse string is : $"

.code

MOV AX,@DATA
MOV DS,AX

LEA DX,MSG1
MOV AH,09H
INT 21H

MOV CX,00H

READ:
MOV AH,01H
INT 21H

CMP AL,0DH	;Carriage return
JE AHEAD
PUSH AX
INC CX
JMP READ


AHEAD:
LEA DX,MSG2
MOV AH,09H
INT 21H

DISPLAY:
MOV AH,02H	;display character
POP DX
INT 21H
LOOP DISPLAY

MOV AH,4CH
INT 21H
END