Program Example16;
uses Crt;

{ Program to demonstrate the Sound and NoSound function. }

var
  i : longint;
begin
  WriteLn('You will hear some tones from your speaker');
  while (i < 15000) do
  begin
    inc(i, 500);
    Sound(i);
    Delay(100);
  end;
  WriteLn('Quiet now!');
  {Stop noise}
  NoSound;
end.
{http://www.freepascal.org/docs-html/rtl/crt/nosound.html}