def setRTS(self,level=1):
        """Set terminal status line: Request To Send"""
        if not self.hComPort: raise portNotOpenError
        if level:
            win32file.EscapeCommFunction(self.hComPort, win32file.SETRTS)
        else:
            win32file.EscapeCommFunction(self.hComPort, win32file.CLRRTS)