Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
     
            Try
                SerialPort1.Close()
                SerialPort1.PortName = "COM5"
                SerialPort1.Open()
            Catch ex As Exception
                MessageBox.Show(ex.Message, "COM5")
            End Try
     
        End Sub