title: How can I discover if a device is connected to a specific serial (COM) port?
body: <p>How can I discover, using C#'s <code>SerialPort</code> class, whether a device is connected to a specific serial (COM) port?</p>
  
  <p>Note: that class's <code>Open</code> method opens the port even if there is no device connected to the port.</p>