title: Custom baud rate
body: <p>I am trying to talk with hardware device through virtual COM port. Host computer is PC Windows OS PC. Device is working with 921600 baud rate. This code works:</p>
  
  <pre>
  DCB dcb;
  ...
  dcb.BaudRate =  CBR_115200;
  SetCommState(hPort, &dcb);
  </pre>
  
  <p>Once I change baud rate:</p>
  
  <pre>
  dcb.BaudRate =  921600;
  </pre>
  
  <p>SetCommState fails with last error <code>0x57</code> (parameter is incorrect). Does this mean that Windows API prevents any baud rate except predefined values? Or maybe, virtual COM port may be configured to allow this baud rate?</p>
  
  <p>Virtual COM port is part of CameraLink connection. I am talking with CameraLink board vendor. But I need to know whether Windows serial communications API support custom baud rates.</p>