Public Class Form2

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        If RadioButton1.Checked Then
            Form1.SerialPort1.BaudRate = 4800
        End If
        If RadioButton2.Checked Then
            Form1.SerialPort1.BaudRate = 9600
        End If
        If RadioButton3.Checked Then
            Form1.SerialPort1.BaudRate = 19200
        End If

        Me.Visible = False
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If Not Form1.SerialPort1.IsOpen Then
            Dim port As String
            port = ListBox1.SelectedItem
            If Not port = Nothing Then
                Form1.SerialPort1.PortName = port
                Dim Title As String = "Port"
                Try   ' Set up structured error handling.

                    CheckForIllegalCrossThreadCalls = False
                    Form1.SerialPort1.Open()
                    'Form1.Timer1.Enabled = True

                Catch ex As Exception When Not Form1.SerialPort1.IsOpen
                    MsgBox("Com Port already in use by another application", MsgBoxStyle.Critical, "Error")

                Finally
                    'Beep()   ' This line is executed no matter what.
                End Try
            Else
                MsgBox("Select a port", MsgBoxStyle.DefaultButton1, "Error")
            End If
        End If
    End Sub

    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim instance As IO.Ports.SerialPort = Form1.SerialPort1
        For Each portName As String In My.Computer.Ports.SerialPortNames
            ListBox1.Items.Add(portName)
        Next
        RadioButton2.Checked = True
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        If Form1.SerialPort1.IsOpen Then
            Form1.SerialPort1.Close()
        End If
    End Sub

End Class 