handling data outside of STX-ETX

For the last two years I have been using the following thread to receive
data.  It has served me well.  I am now in a situation where I have to
accept ACKs, NAKs, and EOTs.  I am lost as to how to modify my code to do
this.  I can't have multiple WaitFor's.
Can someone point me in the right direction?

Thanks


procedure TReadingInfinitiThread.Execute;
begin
  while not Terminated do
  begin
    // read data
    FConn.IOHandler.WaitFor(chr(2));
    Buffer := FConn.IOHandler.ReadLn(chr(3));
    If Not(Terminated) then
    Begin
      ProcessData
    End;
  end;
end;