MOV AX,0600H 
  MOV BH,07 
  MOV CX,0000 
  MOV DX,184FH 
  INT 10H 
  MOV AH,00 
  MOV AL,06 
  INT 10H 
  MOV CX,100 
  MOV DX,50 
BACK: MOV AH,0CH 
  MOV AL,01 
  INT 10H 
  INC CX 
  CMP CX,200 
  JNZ BACK