Public Class ProFeeler
 
    Dim Programm As String
    Dim buf As New Byte
    'Damit der eingehende Wert an die txtprogramm übergen werden kann!
    Private Delegate Sub DelegateSub()
    'Damit der eingehende Wert an die txtprogramm übergen werden kann! Führt 
    ' die Sub Wertübergabe aus!
    Private TextboxAktualisieren As New DelegateSub(AddressOf Wertübergabe)
 
 
    Private Sub ProFeeler_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        Me.Text = "ProFeeler"
        Me.Top = Screen.PrimaryScreen.WorkingArea.Height / 2 - Me.Height / 2
        Me.Left = Screen.PrimaryScreen.WorkingArea.Width / 2 - Me.Width / 2
 
        ' Show all available COM ports.
        For Each sp As String In My.Computer.Ports.SerialPortNames
            ListBox1.Items.Add(sp)
        Next
 
        Port = New System.IO.Ports.SerialPort("COM1")
        SerialPort1.BaudRate = Port.BaudRate
        SerialPort1.StopBits = Port.StopBits
        SerialPort1.DataBits = Port.DataBits
        SerialPort1.ReadBufferSize = Port.ReadBufferSize
        SerialPort1.Parity = Port.Parity
    End Sub    
 
    Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As _
      System.IO.Ports.SerialDataReceivedEventArgs) Handles _
      SerialPort1.DataReceived
        buf = SerialPort1.BaseStream.ReadByte
 
        Me.Invoke(TextboxAktualisieren) 'Damit der eingehende Wert an die 
        ' txtprogramm übergehen werden kann!
    End Sub
 
    Private Sub Wertübergabe()
        txtprogramm.AppendText(buf)
    End Sub    
 
    Private Sub cmdempfangen_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles cmdempfangen.Click
        If SerialPort1.IsOpen = False Then SerialPort1.Open()
    End Sub

fg viperbone