diff --git a/ModbusDemo/App.xaml b/ModbusDemo/App.xaml
index 53a33ed..75bc9c2 100644
--- a/ModbusDemo/App.xaml
+++ b/ModbusDemo/App.xaml
@@ -1,40 +1,47 @@
-<prism:PrismApplication x:Class="ModbusDemo.App"
-             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-             xmlns:local="clr-namespace:ModbusDemo"
-             xmlns:prism="http://prismlibrary.com/"
-             xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
-             >
+<prism:PrismApplication
+    x:Class="ModbusDemo.App"
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:local="clr-namespace:ModbusDemo"
+    xmlns:prism="http://prismlibrary.com/"
+    xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes">
     <Application.Resources>
         <ResourceDictionary>
             <ResourceDictionary.MergedDictionaries>
-                <!-- 使用捆绑的主题，设置基础主题为浅色，主色为深紫色，次色为酸橙色 -->
+                <!--  使用捆绑的主题，设置基础主题为浅色，主色为深紫色，次色为酸橙色  -->
                 <materialDesign:BundledTheme BaseTheme="Light" PrimaryColor="LightBlue" SecondaryColor="Lime" />
 
-                <!-- 引用 Material Design 2 的默认样式 -->
+                <!--  引用 Material Design 2 的默认样式  -->
                 <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesign2.Defaults.xaml" />
             </ResourceDictionary.MergedDictionaries>
 
             <Style x:Key="LeftMenuStyle" TargetType="ListBoxItem">
-                <Setter Property="MinHeight" Value="40"></Setter>
+                <Setter Property="MinHeight" Value="40">
+                </Setter>
                 <Setter Property="Template">
                     <Setter.Value>
                         <ControlTemplate TargetType="ListBoxItem">
                             <Grid>
-                                <Border x:Name="border"></Border>
-                                <ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalAlignment}" VerticalAlignment="{TemplateBinding VerticalAlignment}"></ContentPresenter>
+                                <Border x:Name="border">
+                                </Border>
+                                <ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalAlignment}" VerticalAlignment="{TemplateBinding VerticalAlignment}">
+                                </ContentPresenter>
                             </Grid>
 
-                            <!--触发器-->
+                            <!--  触发器  -->
                             <ControlTemplate.Triggers>
                                 <Trigger Property="IsSelected" Value="True">
-                                    <Setter TargetName="border" Property="Background" Value="{DynamicResource PrimaryHueLightBrush}"></Setter>
-                                    <Setter TargetName="border" Property="Opacity" Value="0.2"></Setter>
+                                    <Setter TargetName="border" Property="Background" Value="{DynamicResource PrimaryHueLightBrush}">
+                                    </Setter>
+                                    <Setter TargetName="border" Property="Opacity" Value="0.2">
+                                    </Setter>
                                 </Trigger>
 
                                 <Trigger Property="IsMouseOver" Value="True">
-                                    <Setter TargetName="border" Property="Background" Value="{DynamicResource PrimaryHueLightBrush}"></Setter>
-                                    <Setter TargetName="border" Property="Opacity" Value="0.2"></Setter>
+                                    <Setter TargetName="border" Property="Background" Value="{DynamicResource PrimaryHueLightBrush}">
+                                    </Setter>
+                                    <Setter TargetName="border" Property="Opacity" Value="0.2">
+                                    </Setter>
                                 </Trigger>
                             </ControlTemplate.Triggers>
                         </ControlTemplate>
diff --git a/ModbusDemo/Device/IModbusRTU.cs b/ModbusDemo/Device/IModbusRTU.cs
index fd17ccc..847e908 100644
--- a/ModbusDemo/Device/IModbusRTU.cs
+++ b/ModbusDemo/Device/IModbusRTU.cs
@@ -9,5 +9,9 @@ namespace ModbusDemo.Device
     interface IModbusRTU
     {
         public bool[] ReadCoil(byte slaveAddress, ushort startAddress, ushort numberOfPoints);
+
+
+        public void WriteCoil(byte slaveAddress, ushort startAddress, bool[] data);
+
     }
 }
diff --git a/ModbusDemo/Device/ModbusRTU.cs b/ModbusDemo/Device/ModbusRTU.cs
index d71b998..0c3fae7 100644
--- a/ModbusDemo/Device/ModbusRTU.cs
+++ b/ModbusDemo/Device/ModbusRTU.cs
@@ -26,7 +26,11 @@ namespace ModbusDemo.Device
         /// <returns></returns>
         public bool[] ReadCoil(byte slaveAddress, ushort startAddress, ushort numberOfPoints)
         {
-
+            if (!_serialPort.IsOpen)
+            {
+                MessageBox.Show("串口没有链接，请先链接");
+                return null;
+            }
             List<byte> sendByteList = new List<byte>();
             //设置从站地址
             sendByteList.Add(slaveAddress);
@@ -89,20 +93,84 @@ namespace ModbusDemo.Device
             }
             //先将字符串转为数组，再反转，再转为字节数组
             char[] chars = result.ToArray().Reverse<char>().ToArray();
-            bool[] f = new bool[numberOfPoints];
+            bool[] ultimately = new bool[numberOfPoints];
             for (int i = 0; i < numberOfPoints; i++)
             {
                 if (chars[i] == '1')
                 {
-                    f[i] = true;
+                    ultimately[i] = true;
                 }
                 else
                 {
-                    f[i] = false;
+                    ultimately[i] = false;
                 }
             }
-            return f;
+            return ultimately;
         }
 
+        public void WriteCoil(byte slaveAddress, ushort startAddress, bool[] data)
+        {
+            List<byte> sendByteList = new List<byte>();
+            //设置从站地址
+            sendByteList.Add(slaveAddress);
+            //设置功能码
+            sendByteList.Add(0x0F);
+            //设置起始地址的高位和低位
+            sendByteList.Add(BitConverter.GetBytes(startAddress)[1]);
+            sendByteList.Add(BitConverter.GetBytes(startAddress)[0]);
+            //设置写入几个线圈
+            sendByteList.Add(BitConverter.GetBytes(data.Length)[1]);
+            sendByteList.Add(BitConverter.GetBytes(data.Length)[0]);
+
+            // 计算字节数
+            int byteCount = (data.Length + 7) / 8;
+            sendByteList.Add((byte)byteCount);
+
+            // 初始化字节数组
+            byte[] coilBytes = new byte[byteCount];
+
+            // 把bool数组转换为字节
+            for (int i = 0; i < data.Length; i++)
+            {
+                int byteIndex = i / 8;
+                int bitIndex = i % 8;
+                if (data[i])
+                {
+                    coilBytes[byteIndex] |= (byte)(1 << bitIndex);
+                }
+            }
+            sendByteList.AddRange(coilBytes);
+
+            //获取CRC校验码
+            byte[] getCRC = sendByteList.ToArray();
+            byte[] resultCRC = CRCUitl.CalculateCRC(getCRC, getCRC.Length);
+            sendByteList.Add(resultCRC[0]);
+            sendByteList.Add(resultCRC[1]);
+
+
+            byte[] sendByte = sendByteList.ToArray();
+            if (_serialPort.IsOpen)
+            {
+                // 清空接收缓冲区（避免残留数据干扰）
+                _serialPort.DiscardInBuffer();
+
+                _serialPort.Write(sendByte, 0, sendByte.Length);
+                Thread.Sleep(300);
+                byte[] response = new byte[_serialPort.BytesToRead];
+                _serialPort.Read(response, 0, _serialPort.BytesToRead);
+
+                //判断发送回来的数据是否正确
+                CheckData.CheckResponse(response);
+
+                if (!CRCUitl.ValidateCRC(response))
+                {
+                    MessageBox.Show("0x14:CRC校验错误");
+                     
+                }
+            }
+
+
+            
+        }
     }
 }
diff --git a/ModbusDemo/VIew/CoilUC.xaml b/ModbusDemo/VIew/CoilUC.xaml
index a0dfbac..3ac4a84 100644
--- a/ModbusDemo/VIew/CoilUC.xaml
+++ b/ModbusDemo/VIew/CoilUC.xaml
@@ -31,6 +31,7 @@
             FontWeight="Black"
             FontSize="16">
         </TextBlock>
+        <!--  定义读取的数据  -->
         <Grid Grid.Row="1">
             <Grid.ColumnDefinitions>
                 <ColumnDefinition>
@@ -44,34 +45,89 @@
                 <ColumnDefinition>
                 </ColumnDefinition>
             </Grid.ColumnDefinitions>
-            <StackPanel Orientation="Vertical" HorizontalAlignment="Center">
-                <TextBlock Text="从站地址" Margin="20"></TextBlock>
-                <TextBox Text="{Binding SlaveAddress}" Margin="0,-10,0,0"></TextBox>
+            <StackPanel HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="从站地址">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding SlaveAddress}">
+                </TextBox>
             </StackPanel>
 
-            <StackPanel Orientation="Vertical" HorizontalAlignment="Center" Grid.Column="1">
-                <TextBlock Text="起始地址" Margin="20"></TextBlock>
-                <TextBox Text="{Binding StartAddress}" Margin="0,-10,0,0"></TextBox>
+            <StackPanel Grid.Column="1" HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="起始地址">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding StartAddress}">
+                </TextBox>
             </StackPanel>
 
-            <StackPanel Orientation="Vertical" HorizontalAlignment="Center" Grid.Column="2">
-                <TextBlock Text="读取位数" Margin="20"></TextBlock>
-                <TextBox Text="{Binding NumberOfPoints}" Margin="0,-10,0,0"></TextBox>
+            <StackPanel Grid.Column="2" HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="读取位数">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding NumberOfPoints}">
+                </TextBox>
             </StackPanel>
 
-            <StackPanel Orientation="Vertical" HorizontalAlignment="Center" Grid.Column="3">
-                <TextBlock Text="读取结果" Margin="20"></TextBlock>
-                <TextBox Text="{Binding ReadResult}" Margin="0,-10,0,0"></TextBox>
+            <StackPanel Grid.Column="3" HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="读取结果">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding ReadResult}">
+                </TextBox>
             </StackPanel>
             <Button
                 Grid.Column="4"
                 Width="80"
                 Height="30"
-                Command="{Binding ReadCoilCmm}"
                 materialDesign:ButtonAssist.CornerRadius="15"
+                Command="{Binding ReadCoilCmm}"
                 Content="读取"
                 Style="{StaticResource MaterialDesignRaisedDarkButton}">
             </Button>
         </Grid>
+        <Grid Grid.Row="2">
+            <Grid.ColumnDefinitions>
+                <ColumnDefinition>
+                </ColumnDefinition>
+                <ColumnDefinition>
+                </ColumnDefinition>
+                <ColumnDefinition>
+                </ColumnDefinition>
+                <ColumnDefinition>
+                </ColumnDefinition>
+                <ColumnDefinition>
+                </ColumnDefinition>
+            </Grid.ColumnDefinitions>
+            <StackPanel HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="从站地址">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding WriteSlaveAddress}">
+                </TextBox>
+            </StackPanel>
+
+            <StackPanel Grid.Column="1" HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="起始地址">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding WriteStartAddress}">
+                </TextBox>
+            </StackPanel>
+
+            <StackPanel Grid.Column="2" HorizontalAlignment="Center" Orientation="Vertical">
+                <TextBlock Margin="20" Text="写入数据">
+                </TextBlock>
+                <TextBox Margin="0,-10,0,0" Text="{Binding WriteData}">
+                </TextBox>
+            </StackPanel>
+            <TextBlock Grid.Column="3" HorizontalAlignment="Center" VerticalAlignment="Center" Text="1代表Ture，0代表flase">
+            </TextBlock>
+
+
+            <Button
+                Grid.Column="4"
+                Width="80"
+                Height="30"
+                materialDesign:ButtonAssist.CornerRadius="15"
+                Command="{Binding WriteCoilCmm}"
+                Content="写入"
+                Style="{StaticResource MaterialDesignRaisedDarkButton}">
+            </Button>
+        </Grid>
     </Grid>
 </UserControl>
diff --git a/ModbusDemo/VIewModel/CoilUCViewModel.cs b/ModbusDemo/VIewModel/CoilUCViewModel.cs
index d03db36..bd50693 100644
--- a/ModbusDemo/VIewModel/CoilUCViewModel.cs
+++ b/ModbusDemo/VIewModel/CoilUCViewModel.cs
@@ -20,6 +20,8 @@ namespace ModbusDemo.VIewModel
         private IModbusRTU _modbusRTU;
         //定义读线圈的命令
         public DelegateCommand ReadCoilCmm { get; set; }
+        //定义写线圈操作
+        public DelegateCommand WriteCoilCmm { get; set; }
         //获取当前使用的串口
         private SerialPort _serialPort;
         //显示当前链接串口的信息
@@ -32,7 +34,7 @@ namespace ModbusDemo.VIewModel
             }
 
         }
-
+        #region 读取定义
 
         //读取的从站id
         private string _slaveAddress;
@@ -46,10 +48,10 @@ namespace ModbusDemo.VIewModel
                 RaisePropertyChanged();
             }
         }
-
+        //读取的起始地址
         private string _startAddress;
 
-        //读取的起始地址
+
         public string StartAddress
         {
             get { return _startAddress; }
@@ -59,10 +61,10 @@ namespace ModbusDemo.VIewModel
                 RaisePropertyChanged();
             }
         }
-
+        //读取的位数
         private string _numberOfPoints;
 
-        //读取的位数
+
         public string NumberOfPoints
         {
             get { return _numberOfPoints; }
@@ -85,9 +87,51 @@ namespace ModbusDemo.VIewModel
                 RaisePropertyChanged();
             }
         }
+        #endregion
+
+        #region 写入定义
+
+        //写入的从站id
+        private string _writeslaveAddress;
+
+        public string WriteSlaveAddress
+        {
+            get { return _writeslaveAddress; }
+            set
+            {
+                _writeslaveAddress = value;
+                RaisePropertyChanged();
+            }
+        }
+        //写入的起始地址
+        private string _writestartAddress;
+
+
+        public string WriteStartAddress
+        {
+            get { return _writestartAddress; }
+            set
+            {
+                _writestartAddress = value;
+                RaisePropertyChanged();
+            }
+        }
+        //写入的数据
+        private string _writeData;
+
 
+        public string WriteData
+        {
+            get { return _writeData; }
+            set
+            {
+                _writeData = value;
+                RaisePropertyChanged();
+            }
+        }
 
 
+        #endregion
         public CoilUCViewModel()
         {
 
@@ -98,30 +142,31 @@ namespace ModbusDemo.VIewModel
             _serialPort = serialPort;
             ReadCoilCmm = new DelegateCommand(ReadCoil);
             _modbusRTU = modbusRTU;
+            WriteCoilCmm = new DelegateCommand(WriteCoil);
         }
 
-        private void ReadCoil()
-        {
 
 
+        /// <summary>
+        /// 线圈读取操作
+        /// </summary>
+        private void ReadCoil()
+        {
             try
             {
                 bool[] result = _modbusRTU.ReadCoil(byte.Parse(SlaveAddress),
                                                 ushort.Parse(StartAddress),
                                                 ushort.Parse(NumberOfPoints));
-
-                if(result != null)
+                if (result != null)
                 {
                     string temp = "";
-                    foreach(var item in result)
+                    foreach (var item in result)
                     {
                         temp += item;
                         temp += " ";
                     }
                     ReadResult = temp;
                 }
-                
-                
             }
             catch (Exception)
             {
@@ -129,9 +174,26 @@ namespace ModbusDemo.VIewModel
                 MessageBox.Show("参数配置错误");
             }
 
-            
+        }
+        private void WriteCoil()
+        {
+            //去除字符串中的空格
+            WriteData =  WriteData.Replace(" ", "");
+            //转换为布尔数组
+            bool[] data =  WriteData.Select(m => m == '1').ToArray();
 
+            try
+            {
+                _modbusRTU.WriteCoil(byte.Parse(WriteSlaveAddress),
+                                     ushort.Parse(WriteStartAddress),
+                                     data);
+            }
+            catch (Exception)
+            {
 
+                MessageBox.Show("信息配置错误");
+            }
+            
         }
     }
 }