Option Explicit On
Option Strict Off
 
Imports System.Threading
Imports System
Imports System.IO.Ports
Imports System.Timers
Imports System.IO
 
Public Class Form1
 
    '02 03 01 00 00 14 44 0a
    Private Sub RS232_Click(sender As System.Object, e As System.EventArgs) _
      Handles RS232.Click
        Try
            SerialPort1.Write({(Chr(&H2)), (Chr(&H3)), (Chr(&H1)), (Chr(&H0)), ( _
              Chr(&H0)), (Chr(&H14)), (Chr(&H44)), (Chr(&HA))}, 0, 8)
            Thread.Sleep(1000)
            SerialPort1.Write({&H2, &H3, &H1, &H0, &H0, &H14, &H44, &HA}, 0, 8)
            Thread.Sleep(1000)
            SerialPort1.Write({&H1, &H3, &H1, &H0, &H0, &H14, &H44, &H39}, 0, 8)
            Thread.Sleep(1000)
            Dim Inputhex As String
            Dim sende As String
            Inputhex = crc.Hex2(2) & crc.Hex2(3) & crc.Hex2(1) & crc.Hex2(0) & _
              crc.Hex2(0) & crc.Hex2(20)
 
            Dim byteBuffer As Byte() = New Byte(0) {} 'Buffer mit 1 Byte
            sende = CRC.AppendModbusCRC16(Inputhex) '# Übergabe des CRC Wertes 
            ' an Var. Sende
            For x = 0 To sende.Length \ 2 - 1 '# Sende einheit
                byteBuffer(0) = Convert.ToByte(sende.Substring(x * 2, 2), 16) _
                  '# String wird in Byte Gewandelt
                SerialPort1.Write(byteBuffer, 0, byteBuffer.Length)   '# Senden 
                ' der Bytes 
            Next x ' # ende der sendeeinheit
 
            'SerialPort1.Close()
        Catch ex As Exception
 
        End Try
 
    End Sub
 
    Private Sub Form1_close(sender As Object, e As _
      System.Windows.Forms.ControlEventArgs) Handles Me.ControlAdded
        SerialPort1.Close()
    End Sub
 
    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) _
      Handles MyBase.Load
        cmbBaud.SelectedIndex = 4
        cmbDataBit.SelectedIndex = 1
        cmbParity.SelectedIndex = 2
        cmbStopBit.SelectedIndex = 0
        For Each s As String In SerialPort.GetPortNames()
            cmbPort.Items.Add(s)
        Next s
        cmbPort.SelectedIndex = 2
    End Sub
    Private Sub btOpenCOM_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles btOpenCOM.Click
        Try
            SerialPort1.PortName = cmbPort.Text
            SerialPort1.BaudRate = Integer.Parse(cmbBaud.Text)
            SerialPort1.DataBits = Integer.Parse(cmbDataBit.Text)
            SerialPort1.Parity = Integer.Parse(cmbParity.Text)
 
            If cmbParity.Text.Substring(0, 1) = "0" Then
                SerialPort1.Parity = Parity.None
            ElseIf cmbParity.Text.Substring(0, 1) = "1" Then
                SerialPort1.Parity = Parity.Odd
            ElseIf cmbParity.Text.Substring(0, 1) = "2" Then
                SerialPort1.Parity = Parity.Even
            ElseIf cmbParity.Text.Substring(0, 1) = "3" Then
                SerialPort1.Parity = Parity.Mark
            End If
 
            If cmbStopBit.Text = "0" Then
                SerialPort1.StopBits = StopBits.None
            ElseIf cmbStopBit.Text = "1" Then
                SerialPort1.StopBits = StopBits.One
            End If
            btOpenCOM.Enabled = False
            btnCloseCOM.Enabled = True
            SerialPort1.Open()
            comOpen = SerialPort1.IsOpen
 
        Catch ex As Exception
            MsgBox(" es ist ein Feheler Aufgetreten !!!!")
        End Try
 
 
    End Sub
    Private Sub btnCloseCOM_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles btnCloseCOM.Click
        SerialPort1.Close()
        btOpenCOM.Enabled = True
        btnCloseCOM.Enabled = False
 
    End Sub
    '#######################################
 
 
End Class

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