Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button1.Click
 
SerialPort1.Write(21)
 
End Sub
 
 
Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As _
  System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
 
        Dim enc As System.Text.Encoding = New System.Text.ASCIIEncoding()
             For I As Integer = 1 To SerialPort1.BytesToRead 
                            Dim ByteArray() As Byte = {.BaseStream.ReadByte}
                            PufferString = enc.GetString(ByteArray)
                            Me.Invoke(Datenanzeigen)       
             Next
 
    End Sub
 
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button2.Click
        Dim s As String
        s = SerialPort1.ReadExisting()
 
        TextBox1.Text = s.ToString
    End Sub

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