Private Sub Receiver(ByVal sender As Object, ByVal e As _
      SerialDataReceivedEventArgs) Handles SerPort.DataReceived
        Try
            Me.BeginInvoke(New StringSubPointer(AddressOf FügenZ2), _
              SerPort.ReadExisting)
        Catch ex As TimeoutException
            MessageBox.Show("Timeout")
        End Try
 
    End Sub
 
    ''' <summary>
    ''' Sub fügt empfangene Teilstrings aus Empfangs-Event zusammen.
    ''' </summary>
    ''' <param name="Buffer">Teilstrings aus Empfang</param>
    ''' <remarks></remarks>
    Private Sub Fügen(ByVal Buffer As String)
        EmpfangZ2 = Empfang + Buffer
        If Buffer.Contains(Chr(13)) Then
            Verarbeitung(Empfang, SerPort)
            Empfang = String.Empty
        End If
 
    End Sub

'Starten beim öffnen des Ports
    Public Sub StartLesen(ByVal sp As SerialPort)
            SerPortReadThread = New Thread( _
            Sub()
                ReadSerialPort(sp)
            End Sub)
    End Sub
 
'Wenn Lesethread des Ports
    Private Sub ReadSerialPort(ByVal sp As SerialPort)
 
        Try
            Do While True
                Dim Empfang As String = sp.ReadTo(Chr(13))
                Invoke( _
                    Sub()
                        Verarbeitung(Empfang, sp)
                    End Sub)
            Loop
        Catch ex As System.TimeoutException
            Application.DoEvents()
            ReadSerialPort(sp)     'Darf ich hier loopen? Verursacht das 
            ' eventuell die Probs?
        Catch ex As ThreadInterruptedException
            ' Thread wurde interrupted.
        Catch ex As Exception
        End Try
 
    End Sub
 
'Beim beenden der Anwendung schließen des Threads
    Public Sub BeendeLesen(ByVal sp As SerialPort)
        If sp.WriteBufferSize = SerPortZ1.WriteBufferSize Then
            SerPortZ1ReadThread.Interrupt()
        Else
            SerPortZ2ReadThread.Interrupt()
        End If
    End Sub

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