private void SetCommStateNative(ref Dcb lpDcb)
 {
     int commErrors = 0;
     Comstat comStat = new Comstat(); for (int i = 0; i < CommStateRetries; i++)
     {
         if (!NativeMethods.ClearCommError(m_Handle, ref commErrors, ref comStat))
         {
             WinIoError();
         }
         if (NativeMethods.SetCommState(m_Handle, ref lpDcb))
         {
             break;
         }
         if (i == CommStateRetries - 1)
         {
             WinIoError();
         }
     }
 }

 private void InitializeDcb()
 {
     Dcb dcb = new Dcb();
     GetCommStateNative(ref dcb);
     log.Info("before dcb flags: "+dcb.Flags);
     dcb.Flags &= ~(1u << DcbFlagAbortOnError);
     log.Info("after dcb flags: " + dcb.Flags);
     SetCommStateNative(ref dcb);
 }

 internal static extern bool SetCommState(SafeFileHandle hFile, ref Dcb lpDcb);

 private void InitializeDcb()
 {
     Dcb dcb = new Dcb();
     GetCommStateNative(ref dcb);
     dcb.Flags &= ~(1u << DcbFlagAbortOnError);
     SetCommStateNative(ref dcb);
 }

 private static extern bool GetCommState(SafeFileHandle hFile, ref Dcb lpDcb);

        private void SetCommStateNative(ref Dcb lpDcb)
        {
            var commErrors = 0;
            var comStat = new Comstat();

            for (var i = 0; i < CommStateRetries; i++)
            {
                if (!ClearCommError(m_Handle, ref commErrors, ref comStat))
                {
                    WinIoError();
                }
                if (SetCommState(m_Handle, ref lpDcb))
                {
                    break;
                }
                if (i == CommStateRetries - 1)
                {
                    WinIoError();
                }
            }
        }