public void BytesToWrite()
{
DGSerial serial1 = new DGSerial(_portName1, _baudRate1);
DGSerial serial2 = new DGSerial(_portName2, _baudRate2);
serial1.Open();
serial2.Open();
byte[] buffertx = DGSerialHelper.StringToBytes("Test1");
serial1.WriteBytes(buffertx);
byte[] bufferrx = serial2.ReadBytes();
Assert.That(serial2.BytesToWrite(), Is.EqualTo(0));
serial1.Close();
serial2.Close();
}