Private Sub Option1_CheckedChanged(ByVal Sender As System.Object, ByVal e As _
  System.EventArgs) Handles Option1.CheckedChanged
        If e.Checked Then
            Dim i As Object
            i = OPENCOM("COM1,1200,N,8,1")
            If i = 0 Then MsgBox("COM1 not available")
            TXD(1)
            RTS(1)
            DTR(1)
        End If
    End Sub