title: VaComm component doesnt fire OnRxChar event
body: <p>VaComm component encapsulates communication with external devices through COM port. My program is communicating with measuring device using following code:</p>
  
  <pre class="lang-c prettyprint-override"><code>void Form::OnButton_Click()
  {
     VaComm1-&gt;PortNum = param.serialComm.port;
     VaComm1-&gt;Open();
     VaComm1-&gt;WriteText("bla bla\r\n");
     Sleep(3000);
     VaComm1-&gt;WriteText("another bla bla");
  }
  </code></pre>
  
  <p>I have set OnRxChar event handler (through form designer) which looks like this:</p>
  
  <pre class="lang-c prettyprint-override"><code>void __fastcall TForm_Main::VaComm1RxChar(TObject *Sender, int Count)
  {
      AnsiString str = VaComm1-&gt;ReadText();
      if (!str.IsEmpty()) 
      {
          // process received data
      }
  }
  </code></pre>
  
  <p>Problem is that this event is not fired even when data were received (can be checked through calling TVaComm::ReadText method in infinite loop). Also sending of two commands to connected device was successfull (can be seen on device display). What else is needed beside opening COM port to receive OnRxChar events when there are some data in input buffer? I also don't understand what is the purpose of sibling component TVaBuffer? Currently i am not using it and can receive data through method ReadText (as i have written above).</p>