diff --git a/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInTcpProtocolLinker.cs b/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInTcpProtocolLinker.cs
index 9796b85..acb9e72 100644
--- a/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInTcpProtocolLinker.cs
+++ b/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInTcpProtocolLinker.cs
@@ -24,7 +24,7 @@ namespace Modbus.Net.Modbus
         public ModbusAsciiInTcpProtocolLinker(string ip, int port)
             : base(ip, port)
         {
-            ((BaseConnector)BaseConnector).AddController(new FifoController(int.Parse(ConfigurationReader.GetValue("TCP:" + ip + ":" + port, "FetchSleepTime")), lengthCalc: content => { var ans = 0; for (int i = 9; i < 13; i++) { ans = ans * 10 + (content[i] - 48); } return ans; }, waitingListMaxCount: ConfigurationReader.GetValue("TCP:" + ip + ":" + port, "WaitingListCount") != null ? int.Parse(ConfigurationReader.GetValue("TCP:" + ip + ":" + port, "WaitingListCount")) : null));
+            ((BaseConnector)BaseConnector).AddController(new FifoController(int.Parse(ConfigurationReader.GetValue("TCP:" + ip + ":" + port, "FetchSleepTime")), lengthCalc: content => { if (content[0] != 0x3a) return -1; for (int i = 1; i < content.Length; i++) { if (content[i - 1] == 0x0D && content[i] == 0x0A) return i + 1; } return -1; }, waitingListMaxCount: ConfigurationReader.GetValue("TCP:" + ip + ":" + port, "WaitingListCount") != null ? int.Parse(ConfigurationReader.GetValue("TCP:" + ip + ":" + port, "WaitingListCount")) : null));
         }
 
         /// <summary>
diff --git a/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInUdpProtocolLinker.cs b/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInUdpProtocolLinker.cs
index 1a12d8c..5f6c274 100644
--- a/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInUdpProtocolLinker.cs
+++ b/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiInUdpProtocolLinker.cs
@@ -24,7 +24,7 @@ namespace Modbus.Net.Modbus
         public ModbusAsciiInUdpProtocolLinker(string ip, int port)
             : base(ip, port)
         {
-            ((BaseConnector)BaseConnector).AddController(new FifoController(int.Parse(ConfigurationReader.GetValue("UDP:" + ip + ":" + port, "FetchSleepTime")), lengthCalc: content => { var ans = 0; for (int i = 9; i < 13; i++) { ans = ans * 10 + (content[i] - 48); } return ans; }, waitingListMaxCount: ConfigurationReader.GetValue("UDP:" + ip + ":" + port, "WaitingListCount") != null ? int.Parse(ConfigurationReader.GetValue("UDP:" + ip + ":" + port, "WaitingListCount")) : null));
+            ((BaseConnector)BaseConnector).AddController(new FifoController(int.Parse(ConfigurationReader.GetValue("UDP:" + ip + ":" + port, "FetchSleepTime")), lengthCalc: content => { if (content[0] != 0x3a) return -1; for (int i = 1; i < content.Length; i++) { if (content[i - 1] == 0x0D && content[i] == 0x0A) return i + 1; } return -1; }, waitingListMaxCount: ConfigurationReader.GetValue("UDP:" + ip + ":" + port, "WaitingListCount") != null ? int.Parse(ConfigurationReader.GetValue("UDP:" + ip + ":" + port, "WaitingListCount")) : null));
         }
 
         /// <summary>
diff --git a/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiProtocolLinker.cs b/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiProtocolLinker.cs
index 8bb9f6c..6eb76e4 100644
--- a/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiProtocolLinker.cs
+++ b/Modbus.Net/Modbus.Net.Modbus/ModbusAsciiProtocolLinker.cs
@@ -16,7 +16,7 @@ namespace Modbus.Net.Modbus
         public ModbusAsciiProtocolLinker(string com, int slaveAddress)
             : base(com, slaveAddress)
         {
-            ((BaseConnector)BaseConnector).AddController(new MatchController(new ICollection<(int, int)>[] { new List<(int, int)> { (1, 1), (2, 2) }, new List<(int, int)> { (3, 3), (4, 4) } }, int.Parse(ConfigurationReader.GetValue("COM:" + com + ":" + slaveAddress, "FetchSleepTime")), lengthCalc: content => { var ans = 0; for (int i = 9; i < 13; i++) { ans = ans * 10 + (content[i] - 48); } return ans; }, waitingListMaxCount: ConfigurationReader.GetValue("COM:" + com + ":" + slaveAddress, "WaitingListCount") != null ? int.Parse(ConfigurationReader.GetValue("COM:" + com + ":" + slaveAddress, "WaitingListCount")) : null));
+            ((BaseConnector)BaseConnector).AddController(new MatchController(new ICollection<(int, int)>[] { new List<(int, int)> { (1, 1), (2, 2) }, new List<(int, int)> { (3, 3), (4, 4) } }, int.Parse(ConfigurationReader.GetValue("COM:" + com + ":" + slaveAddress, "FetchSleepTime")), lengthCalc: content => { if (content[0] != 0x3a) return -1; for (int i = 1; i < content.Length; i++) { if (content[i - 1] == 0x0D && content[i] == 0x0A) return i + 1; } return -1; }, waitingListMaxCount: ConfigurationReader.GetValue("COM:" + com + ":" + slaveAddress, "WaitingListCount") != null ? int.Parse(ConfigurationReader.GetValue("COM:" + com + ":" + slaveAddress, "WaitingListCount")) : null));
         }
 
         /// <summary>
diff --git a/Modbus.Net/Modbus.Net/Connector/ComConnector.cs b/Modbus.Net/Modbus.Net/Connector/ComConnector.cs
index fc79a17..f3238be 100644
--- a/Modbus.Net/Modbus.Net/Connector/ComConnector.cs
+++ b/Modbus.Net/Modbus.Net/Connector/ComConnector.cs
@@ -85,7 +85,7 @@ namespace Modbus.Net
         /// <summary>
         /// 缓冲的字节流
         /// </summary>
-        private List<byte> cachedBytes = new List<byte>();
+        private List<byte> _cachedBytes = new List<byte>();
 
         /// <summary>
         ///     构造器
@@ -488,23 +488,32 @@ namespace Modbus.Net
                         logger.LogDebug(
                             $"Com client {ConnectionToken} receive msg: {string.Concat(returnBytes.Select(p => " " + p.ToString("X2")))}");
 
-                        cachedBytes.AddRange(returnBytes);
-                        var isMessageConfirmed = Controller.ConfirmMessage(cachedBytes.ToArray());
+                        lock (_cachedBytes)
+                        {
+                            _cachedBytes.AddRange(returnBytes);
+                        }
+                        var isMessageConfirmed = Controller.ConfirmMessage(_cachedBytes.ToArray());
                         foreach (var confirmed in isMessageConfirmed)
                         {
                             if (confirmed.Item2 == false)
                             {
                                 //主动传输事件
                             }
-                            cachedBytes.RemoveRange(0, confirmed.Item1.Length);
+                            lock (_cachedBytes)
+                            {
+                                _cachedBytes.RemoveRange(0, confirmed.Item1.Length);
+                            }
                         }
-                        if (isMessageConfirmed.Count > 0 && cachedBytes.Count > 0)
+                        if (isMessageConfirmed.Count > 0 && _cachedBytes.Count > 0)
                         {
                             logger.LogError("Com client {ConnectionToken} cached msg error: {Length}", ConnectionToken,
-                                cachedBytes.Count);
+                                _cachedBytes.Count);
                             logger.LogError(
-                                $"Com client {ConnectionToken} cached msg: {string.Concat(cachedBytes.Select(p => " " + p.ToString("X2")))}");
-                            cachedBytes.Clear();
+                                $"Com client {ConnectionToken} cached msg: {string.Concat(_cachedBytes.Select(p => " " + p.ToString("X2")))}");
+                            lock (_cachedBytes)
+                            {
+                                _cachedBytes.Clear();
+                            }
                         }
                         RefreshReceiveCount();
                     }
diff --git a/Modbus.Net/Modbus.Net/Controller/BaseController.cs b/Modbus.Net/Modbus.Net/Controller/BaseController.cs
index 155c18b..ee4da80 100644
--- a/Modbus.Net/Modbus.Net/Controller/BaseController.cs
+++ b/Modbus.Net/Modbus.Net/Controller/BaseController.cs
@@ -111,7 +111,7 @@ namespace Modbus.Net
             Array.Copy(receiveMessage, receiveMessageCopy, receiveMessage.Length);
             var length = LengthCalc?.Invoke(receiveMessageCopy);
             List<byte[]> duplicatedMessages;
-            if (length == null) return ans;
+            if (length == null || length == -1) return ans;
             else
             {
                 duplicatedMessages = new List<byte[]>();
@@ -119,6 +119,7 @@ namespace Modbus.Net
                 {
                     duplicatedMessages.Add(receiveMessageCopy.Take(length.Value).ToArray());
                     receiveMessageCopy = receiveMessageCopy.TakeLast(receiveMessage.Length - length.Value).ToArray();
+                    if (receiveMessageCopy.Length == 0) break;
                     length = LengthCalc?.Invoke(receiveMessageCopy);
                     if (length == -1) break;
                 }