TITLE PROGRAM 5-2: MODIFIED VERSION OF PROGRAM 5-1
  .MODEL SMALL
  .STACK
  .DATA
  MESSAGE DB 'TO STOP THE BELL SOUND PRESS Q (or q) KEY$'
  .CODE
  MAIN PROC
  MOV AX,@DATA
  MOV DS,AX
  MOV AH,09
  MOV DX,OFFSET MESSAGE 
  INT 21H
AGAIN:MOV AH,02
  MOV DL,07 
  INT 21H
  MOV AH,01 
  INT 16H 
  JZ AGAIN 
  MOV AH,0 
  INT 16H 
  CMP AL,'Q' 
  JE EXIT 
  CMP AL,'q' 
  JE EXIT 
  JMP AGAIN 
EXIT: MOV AH,4CH 
  INT 21H
  MAIN ENDP
  END