更新20260518

Services/ModbusTcpPlcService.cs

@@ -15,6 +15,7 @@ namespace TabletTester2025.Services
 
         private readonly PlcConfiguration _config;
         private readonly SemaphoreSlim _connectLock = new(1, 1);
+        private readonly SemaphoreSlim _ioLock = new(1, 1);
         private TcpClient? _tcpClient;
         private IModbusMaster? _master;
 
@@ -149,10 +150,11 @@ namespace TabletTester2025.Services
 
         private async Task<T> ExecuteAsync<T>(Func<IModbusMaster, Task<T>> action)
         {
-            await EnsureConnectedAsync();
-
+            await _ioLock.WaitAsync();
             try
             {
+                await EnsureConnectedAsync();
+
                 if (_master == null)
                     throw new InvalidOperationException("PLC连接未初始化");
 
@@ -163,9 +165,20 @@ namespace TabletTester2025.Services
                 CloseConnection();
                 throw;
             }
+            finally
+            {
+                _ioLock.Release();
+            }
         }
 
-        private static float RegistersToFloat(ushort highWord, ushort lowWord)
+        private float RegistersToFloat(ushort firstRegister, ushort secondRegister)
+        {
+            return _config.FloatWordOrder == PlcFloatWordOrder.HighWordFirst
+                ? WordsToFloat(firstRegister, secondRegister)
+                : WordsToFloat(secondRegister, firstRegister);
+        }
+
+        private static float WordsToFloat(ushort highWord, ushort lowWord)
         {
             byte[] bytes =
             {
@@ -177,14 +190,15 @@ namespace TabletTester2025.Services
             return BitConverter.ToSingle(bytes, 0);
         }
 
-        private static ushort[] FloatToRegisters(float value)
+        private ushort[] FloatToRegisters(float value)
         {
             byte[] bytes = BitConverter.GetBytes(value);
-            return new[]
-            {
-                (ushort)((bytes[3] << 8) | bytes[2]),
-                (ushort)((bytes[1] << 8) | bytes[0])
-            };
+            ushort highWord = (ushort)((bytes[3] << 8) | bytes[2]);
+            ushort lowWord = (ushort)((bytes[1] << 8) | bytes[0]);
+
+            return _config.FloatWordOrder == PlcFloatWordOrder.HighWordFirst
+                ? new[] { highWord, lowWord }
+                : new[] { lowWord, highWord };
         }
 
         private void CloseConnection()
@@ -200,6 +214,7 @@ namespace TabletTester2025.Services
         {
             CloseConnection();
             _connectLock.Dispose();
+            _ioLock.Dispose();
         }
     }