ModbusTcp通信C#WPF开发测试(基于Nmodbus4库应用)

Easy系列PLC MODBUSTCP通信交换数据

Easy系列PLC MODBUSTCP通信交换数据-CSDN博客文章浏览阅读1k次，点赞18次，收藏15次。CODESYS MODBUS TCP通信请参考下面相关文章链接：CODESYS MODBUS TCP通信(禾川Q1 PLC作为MODBUS TCP从站)_codesys跟禾川通讯-CSDN博客禾川Q1 PLC MODBUS TCP 通信(PLC作为MODBUS TCP通信主站)禾川Q1 PLC MODBUS TCP通信(CODESYS平台完整配置+代码)-CSDN博客文章浏览阅读28次。_plc modbustcphttps://rxxw-control.blog.csdn.net/article/details/148965984?spm=1011.2415.3001.5331

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1、网络拓扑

2、NModbus4包安装

最新的是NModbus包，函数和使用会有所不同，需要注意。这篇文章都是基于NModbus4库的使用和测试。

3、写线圈测试

本地回环测试IP地址固定为127.0.0.1，和第三方设备通信需要准确填写设备IP地址端口号已经MODBUS站号。

4、读线圈测试

5、MainWindow.xaml(界面代码)

XML 复制代码

<Window x:Class="ModbusNModbusDemo.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="ModbusTcp线圈读写(NModbus4)" Height="380" Width="520">
    <Grid Margin="12">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="85"/>
            <ColumnDefinition Width="120"/>
            <ColumnDefinition Width="95"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>

        <!--IP、端口、从站ID-->
        <TextBlock Grid.Row="0" Grid.Column="0" Text="IP地址：" VerticalAlignment="Center"/>
        <TextBox x:Name="txtIp" Grid.Row="0" Grid.Column="1" Text="127.0.0.1" Margin="0,4"/>

        <TextBlock Grid.Row="0" Grid.Column="2" Text="端口：" VerticalAlignment="Center"/>
        <TextBox x:Name="txtPort" Grid.Row="0" Grid.Column="3" Text="502" Width="70" Margin="0,4"/>

        <TextBlock Grid.Row="1" Grid.Column="0" Text="从站ID：" VerticalAlignment="Center"/>
        <TextBox x:Name="txtSlaveId" Grid.Row="1" Grid.Column="1" Text="1" Margin="0,4"/>

        <!--线圈地址-->
        <TextBlock Grid.Row="2" Grid.Column="0" Text="线圈地址：" VerticalAlignment="Center"/>
        <TextBox x:Name="txtCoilAddr" Grid.Row="2" Grid.Column="1" Text="0" Margin="0,4"/>

        <!--批量数量-->
        <TextBlock Grid.Row="2" Grid.Column="2" Text="批量点数：" VerticalAlignment="Center"/>
        <TextBox x:Name="txtBatchCount" Grid.Row="2" Grid.Column="3" Text="8" Width="70" Margin="0,4"/>

        <!--连接/断开+状态-->
        <StackPanel Grid.Row="3" Grid.ColumnSpan="4" Orientation="Horizontal" Margin="0,8,0,8">
            <Button x:Name="BtnConnect" Content="连接PLC" Width="90" Click="BtnConnect_Click"/>
            <Button x:Name="BtnDisConnect" Content="断开连接" Width="90" Margin="8,0,0,0" Click="BtnDisConnect_Click"/>
            <TextBlock x:Name="tbConnState" Text="未连接" Foreground="Red" Margin="15,0,0,0" VerticalAlignment="Center"/>
        </StackPanel>

        <!--单线圈操作按钮-->
        <StackPanel Grid.Row="4" Grid.ColumnSpan="4" Orientation="Horizontal">
            <Button x:Name="BtnSetSingle" Content="线圈置ON" Width="95" Click="BtnSetSingle_Click"/>
            <Button x:Name="BtnResetSingle" Content="线圈置OFF" Width="95" Margin="8,0,0,0" Click="BtnResetSingle_Click"/>
            <Button x:Name="BtnReadSingle" Content="读取单线圈" Width="95" Margin="8,0,0,0" Click="BtnReadSingle_Click"/>
            <Button x:Name="BtnBatchWrite" Content="批量写线圈" Width="95" Margin="8,0,0,0" Click="BtnBatchWrite_Click"/>
        </StackPanel>

        <!--结果显示-->
        <TextBlock Grid.Row="5" Grid.ColumnSpan="4" x:Name="tbResult" Margin="0,12,0,0" FontSize="13"/>
    </Grid>
</Window>

6、MainWindow.xaml.cs(逻辑代码)

cs 复制代码

using System;
using System.Net.Sockets;
using System.Threading.Tasks;
using System.Windows;
using Modbus.Device;

namespace ModbusNModbusDemo
{
    public partial class MainWindow : Window
    {
        private TcpClient _modbusTcpClient;
        private IModbusMaster _modbusMaster;
        public bool IsConnected => _modbusTcpClient != null && _modbusTcpClient.Connected;

        public MainWindow()
        {
            InitializeComponent();
            tbConnState.Text = "未连接";
            tbConnState.Foreground = System.Windows.Media.Brushes.Red;
        }

        #region 连接断开【异步】
        private async void BtnConnect_Click(object sender, RoutedEventArgs e)
        {
            if (IsConnected)
            {
                MessageBox.Show("已经处于连接状态！");
                return;
            }
            if (!CheckParams(out string ip, out int port, out byte slaveId, out _)) return;
            try
            {
                // 异步连接不卡UI
                _modbusTcpClient = new TcpClient();
                await _modbusTcpClient.ConnectAsync(ip, port);
                _modbusMaster = ModbusIpMaster.CreateIp(_modbusTcpClient);

                tbConnState.Text = "连接成功";
                tbConnState.Foreground = System.Windows.Media.Brushes.Green;
                MessageBox.Show("ModbusTCP连接建立成功");
            }
            catch (Exception ex)
            {
                CloseConnect();
                MessageBox.Show("连接失败：" + ex.Message);
            }
        }

        private void BtnDisConnect_Click(object sender, RoutedEventArgs e)
        {
            CloseConnect();
            MessageBox.Show("已断开通信连接");
        }

        void CloseConnect()
        {
            if (_modbusTcpClient != null)
            {
                _modbusTcpClient.Close();
                _modbusTcpClient.Dispose();
                _modbusTcpClient = null;
            }
            _modbusMaster = null;
            tbConnState.Text = "未连接";
            tbConnState.Foreground = System.Windows.Media.Brushes.Red;
        }
        #endregion

        #region 单线圈操作 异步
        private async void BtnSetSingle_Click(object sender, RoutedEventArgs e)
        {
            if (!CheckConnectState()) return;
            await WriteSingleCoil(true);
        }
        private async void BtnResetSingle_Click(object sender, RoutedEventArgs e)
        {
            if (!CheckConnectState()) return;
            await WriteSingleCoil(false);
        }

        async Task WriteSingleCoil(bool state)
        {
            if (!CheckParams(out _, out _, out byte slaveId, out ushort addr)) return;
            try
            {
                // 同步Modbus方法套Task.Run脱离UI线程
                await Task.Run(() =>
                {
                    _modbusMaster.WriteSingleCoil(slaveId, addr, state);
                });
                MessageBox.Show($"线圈{addr} {(state ? "置位成功ON" : "复位成功OFF")}");
            }
            catch (Exception ex)
            {
                MessageBox.Show("写入异常：" + ex.Message);
                CloseConnect();
            }
        }

        private async void BtnReadSingle_Click(object sender, RoutedEventArgs e)
        {
            if (!CheckConnectState()) return;
            if (!CheckParams(out _, out _, out byte slaveId, out ushort addr)) return;
            try
            {
                bool[] resArr = await Task.Run(() =>
                {
                    return _modbusMaster.ReadCoils(slaveId, addr, 1);
                });
                tbResult.Text = $"线圈{addr} 状态：{(resArr[0] ? "ON" : "OFF")}";
            }
            catch (Exception ex)
            {
                tbResult.Text = "读取失败：" + ex.Message;
                CloseConnect();
            }
        }
        #endregion

        #region 批量写线圈
        private async void BtnBatchWrite_Click(object sender, RoutedEventArgs e)
        {
            if (!CheckConnectState()) return;
            if (!CheckParams(out _, out _, out byte slaveId, out ushort startAddr)) return;
            if (!ushort.TryParse(txtBatchCount.Text, out ushort count) || count < 1)
            {
                MessageBox.Show("批量点数填写错误");
                return;
            }
            bool[] batchData = new bool[count];
            for (int i = 0; i < count; i++)
                batchData[i] = i % 2 == 0;

            try
            {
                await Task.Run(() =>
                {
                    _modbusMaster.WriteMultipleCoils(slaveId, startAddr, batchData);
                });
                MessageBox.Show($"从地址{startAddr}开始，共{count}个线圈批量写入完成！");
            }
            catch (Exception ex)
            {
                MessageBox.Show("批量写入异常：" + ex.Message);
                CloseConnect();
            }
        }
        #endregion

        #region 辅助方法
        bool CheckConnectState()
        {
            if (!IsConnected)
            {
                MessageBox.Show("请先建立ModbusTCP连接！");
                return false;
            }
            return true;
        }

        bool CheckParams(out string ip, out int port, out byte slaveId, out ushort coilAddr)
        {
            ip = txtIp.Text.Trim();
            port = 0; slaveId = 0; coilAddr = 0;
            if (!int.TryParse(txtPort.Text, out port) || port < 1 || port > 65535)
            {
                MessageBox.Show("端口数字错误");
                return false;
            }
            if (!byte.TryParse(txtSlaveId.Text, out slaveId) || slaveId < 1)
            {
                MessageBox.Show("从站ID范围1~247");
                return false;
            }
            if (!ushort.TryParse(txtCoilAddr.Text, out coilAddr))
            {
                MessageBox.Show("线圈地址非负整数");
                return false;
            }
            return true;
        }
        #endregion
    }
}

7、启用轮询

我们更换了一个界面，界面里总共2个设备。在同一个端口下RS485总线挂接了2个从站设备。

8、监控的RS485总线数据帧

9、对应界面代码(MainWindow.xaml)