diff --git a/csharp/Lib/Protocols/Modbus/Clients/ModbusClient.cs b/csharp/Lib/Protocols/Modbus/Clients/ModbusClient.cs
index c992d0874..0a4ca6948 100644
--- a/csharp/Lib/Protocols/Modbus/Clients/ModbusClient.cs
+++ b/csharp/Lib/Protocols/Modbus/Clients/ModbusClient.cs
@@ -1,8 +1,6 @@
 using InnovEnergy.Lib.Protocols.Modbus.Connections;
 using InnovEnergy.Lib.Protocols.Modbus.Conversions;
 using InnovEnergy.Lib.Protocols.Modbus.Protocol;
-using static InnovEnergy.Lib.Protocols.Modbus.Protocol.MultiRegisterEndianness;
-using static InnovEnergy.Lib.Protocols.Modbus.Protocol.RegisterIndexing;
 
 namespace InnovEnergy.Lib.Protocols.Modbus.Clients;
 
@@ -15,9 +13,7 @@ public abstract class ModbusClient
 {
     protected ModbusConnection        Connection       { get; }
     protected Byte                    SlaveId          { get; }
-    protected RegisterIndexing        RegisterIndexing { get; }
-    protected MultiRegisterEndianness Endianness       { get; }
-
+    
 
     // TODO: add additional functions: coils...
     
@@ -45,19 +41,14 @@ public abstract class ModbusClient
     }
     
     protected ModbusClient(ModbusConnection connection, 
-                                       Byte slaveId,
-                           RegisterIndexing registerIndexing = OneBased,
-                    MultiRegisterEndianness endianness = LittleEndian)
+                                       Byte slaveId)
     {
         Connection       = connection;
         SlaveId          = slaveId;
-        RegisterIndexing = registerIndexing;
-        Endianness       = endianness;
     }
 
     public void CloseConnection() => Connection.Close();
     
-    protected UInt16 LogicToWire(UInt16 address) => RegisterIndexing.LogicToSerialized(address);
-    protected UInt16 SerializedToLogic(UInt16 address) => RegisterIndexing.SerializedToLogic(address);
+    
 }
 
diff --git a/csharp/Lib/Protocols/Modbus/Clients/ModbusRtuClient.cs b/csharp/Lib/Protocols/Modbus/Clients/ModbusRtuClient.cs
index c49456ab0..24171c847 100644
--- a/csharp/Lib/Protocols/Modbus/Clients/ModbusRtuClient.cs
+++ b/csharp/Lib/Protocols/Modbus/Clients/ModbusRtuClient.cs
@@ -30,9 +30,7 @@ public class ModbusRtuClient : ModbusClient
 
     public override ModbusRegisters ReadInputRegisters(UInt16 readAddress, UInt16 nValues)
     {
-        var wireReadAddress = LogicToWire(readAddress);
-        
-        var cmd = new ReadInputRegistersCommandFrame(SlaveId, wireReadAddress, nValues);
+        var cmd = new ReadInputRegistersCommandFrame(SlaveId, readAddress, nValues);
         var crc = CalcCrc(cmd);
 
         // TX
@@ -56,9 +54,7 @@ public class ModbusRtuClient : ModbusClient
 
     public override ModbusRegisters ReadHoldingRegisters(UInt16 readAddress, UInt16 nValues)
     {
-        var wireReadAddress = LogicToWire(readAddress);
-        
-        var cmd = new ReadHoldingRegistersCommandFrame(SlaveId, wireReadAddress, nValues);
+        var cmd = new ReadHoldingRegistersCommandFrame(SlaveId, readAddress, nValues);
         var crc = CalcCrc(cmd.Data);
 
         // TX
@@ -86,9 +82,7 @@ public class ModbusRtuClient : ModbusClient
 
     public override UInt16 WriteRegisters(UInt16 writeAddress, UInt16s values)
     {
-        var wireWriteAddress = LogicToWire(writeAddress);
-        
-        var cmd = new WriteRegistersCommandFrame(SlaveId, wireWriteAddress, values);
+        var cmd = new WriteRegistersCommandFrame(SlaveId, writeAddress, values);
         var crc = CalcCrc(cmd);
         var nToRead = cmd.ExpectedResponseSize + CrcSize;
 
@@ -111,13 +105,10 @@ public class ModbusRtuClient : ModbusClient
 
     public override ModbusRegisters ReadWriteRegisters(UInt16 readAddress, UInt16 nbToRead, UInt16 writeAddress, UInt16s registersToWrite)
     {
-        var wireReadAddress = LogicToWire(readAddress);
-        var wireWriteAddress = LogicToWire(writeAddress);
-        
         var cmd = new ReadWriteRegistersCommandFrame(SlaveId, 
-                                                     wireReadAddress,
+                                                     readAddress,
                                                      nbToRead, 
-                                                     wireWriteAddress, 
+                                                     writeAddress, 
                                                      registersToWrite);
         var crc = CalcCrc(cmd);
 
diff --git a/csharp/Lib/Protocols/Modbus/Clients/ModbusTcpClient.cs b/csharp/Lib/Protocols/Modbus/Clients/ModbusTcpClient.cs
index 2952d4243..795cb9189 100644
--- a/csharp/Lib/Protocols/Modbus/Clients/ModbusTcpClient.cs
+++ b/csharp/Lib/Protocols/Modbus/Clients/ModbusTcpClient.cs
@@ -1,11 +1,10 @@
 using System.Diagnostics;
 using InnovEnergy.Lib.Protocols.Modbus.Connections;
 using InnovEnergy.Lib.Protocols.Modbus.Conversions;
-using InnovEnergy.Lib.Protocols.Modbus.Protocol;
 using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Commands;
 using InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Replies;
 using InnovEnergy.Lib.Protocols.Modbus.Tcp;
-using static InnovEnergy.Lib.Protocols.Modbus.Protocol.MultiRegisterEndianness;
+
 
 namespace InnovEnergy.Lib.Protocols.Modbus.Clients;
 
@@ -21,21 +20,16 @@ public class ModbusTcpClient : ModbusClient
     private UInt16 NextId() => unchecked(++_Id);
 
 
-    public ModbusTcpClient(ModbusConnection connection, 
-                                       Byte slaveId, 
-                           RegisterIndexing registerIndexing = RegisterIndexing.OneBased, 
-                    MultiRegisterEndianness endianness = LittleEndian) : base(connection, slaveId, registerIndexing, endianness)
+    public ModbusTcpClient(ModbusConnection connection, Byte slaveId) : base(connection, slaveId)
     {
     }
 
     
     public override IReadOnlyList<Boolean> ReadDiscreteInputs(UInt16 readAddress, UInt16 nValues)
     {
-        var wireReadAddress = LogicToWire(readAddress);
-
         var id  = NextId(); // TODO: check response id
         
-        var cmd = new ReadDiscreteInputsCommandFrame(SlaveId, wireReadAddress, nValues);
+        var cmd = new ReadDiscreteInputsCommandFrame(SlaveId, readAddress, nValues);
         var hdr = new MbapHeader(id, cmd.Data.Count);  
         var frm = new ModbusTcpFrame(hdr, cmd);         
 
@@ -52,10 +46,9 @@ public class ModbusTcpClient : ModbusClient
 
     public override ModbusRegisters ReadInputRegisters(UInt16 readAddress, UInt16 nValues)
     {
-        var wireReadAddress = LogicToWire(readAddress);
         var id  = NextId(); // TODO: check response id
 
-        var cmd = new ReadInputRegistersCommandFrame(SlaveId, wireReadAddress, nValues);
+        var cmd = new ReadInputRegistersCommandFrame(SlaveId, readAddress, nValues);
         var hdr = new MbapHeader(id, cmd.Data.Count);
         var frm = new ModbusTcpFrame(hdr, cmd);
 
@@ -77,10 +70,8 @@ public class ModbusTcpClient : ModbusClient
 
     public override ModbusRegisters ReadHoldingRegisters(UInt16 readAddress, UInt16 nValues)
     {
-        var wireReadAddress = LogicToWire(readAddress);
-
         var id  = NextId(); // TODO: check response id
-        var cmd = new ReadHoldingRegistersCommandFrame(SlaveId, wireReadAddress, nValues);
+        var cmd = new ReadHoldingRegistersCommandFrame(SlaveId, readAddress, nValues);
         var hdr = new MbapHeader(id, cmd.Data.Count);
         var frm = new ModbusTcpFrame(hdr, cmd);
 
@@ -99,10 +90,8 @@ public class ModbusTcpClient : ModbusClient
 
     public override UInt16 WriteMultipleCoils(UInt16 writeAddress, Coils coils)
     {
-        var wireWriteAddress = LogicToWire(writeAddress);
-         
-        var id  = NextId(); // TODO: check response id
-        var cmd = new WriteCoilsCommandFrame(SlaveId, wireWriteAddress, coils);
+       var id  = NextId(); // TODO: check response id
+        var cmd = new WriteCoilsCommandFrame(SlaveId, writeAddress, coils);
         var hdr = new MbapHeader(id, cmd.Data.Count);
         var frm = new ModbusTcpFrame(hdr, cmd);
 
@@ -120,10 +109,8 @@ public class ModbusTcpClient : ModbusClient
     
     public override UInt16 WriteRegisters(UInt16 writeAddress, UInt16s values)
     {
-        var wireWriteAddress = LogicToWire(writeAddress);
-
         var id  = NextId(); // TODO: check response id
-        var cmd = new WriteRegistersCommandFrame(SlaveId, wireWriteAddress, values);
+        var cmd = new WriteRegistersCommandFrame(SlaveId, writeAddress, values);
         var hdr = new MbapHeader(id, cmd.Data.Count);
         var frm = new ModbusTcpFrame(hdr, cmd);
 
@@ -142,15 +129,14 @@ public class ModbusTcpClient : ModbusClient
 
     public override ModbusRegisters ReadWriteRegisters(UInt16 readAddress, UInt16 nbToRead, UInt16 writeAddress, UInt16s registersToWrite)
     {
-        var wireReadAddress  = LogicToWire(readAddress);
-        var wireWriteAddress = LogicToWire(writeAddress);
+
         
         var id  = NextId(); // TODO: check response id
         
         var cmd = new ReadWriteRegistersCommandFrame(SlaveId, 
-                                                     wireReadAddress, 
+                                                     readAddress, 
                                                      nbToRead, 
-                                                     wireWriteAddress, 
+                                                     writeAddress, 
                                                      registersToWrite);
         
         var hdr = new MbapHeader(id, cmd.Data.Count);
diff --git a/csharp/Lib/Protocols/Modbus/Protocol/Frames/Accessors/MbRegisters.cs b/csharp/Lib/Protocols/Modbus/Protocol/Frames/Accessors/MbRegisters.cs
index 6db8492b9..6ff463460 100644
--- a/csharp/Lib/Protocols/Modbus/Protocol/Frames/Accessors/MbRegisters.cs
+++ b/csharp/Lib/Protocols/Modbus/Protocol/Frames/Accessors/MbRegisters.cs
@@ -1,6 +1,5 @@
 using System.Collections;
 using InnovEnergy.Lib.Utils;
-using static InnovEnergy.Lib.Protocols.Modbus.Protocol.MultiRegisterEndianness;
 
 namespace InnovEnergy.Lib.Protocols.Modbus.Protocol.Frames.Accessors;
 
@@ -10,22 +9,11 @@ public struct MbRegisters : IReadOnlyList<UInt16>
 {
     private MbWords                 Words         { get; }
     private UInt16                  StartRegister { get; }
-    private MultiRegisterEndianness Endianness    { get; }
     
-    public MbRegisters(MbWords words, 
-                        UInt16 startRegister,
-       MultiRegisterEndianness endianness,
-              RegisterIndexing registerIndexing)
+    public MbRegisters(MbWords words,  UInt16 startRegister)
     {
-        Words      = words;
-        Endianness = endianness;
-
-        var start = startRegister - (Int16) registerIndexing; // TODO: check
-
-        if (start < 0)
-            throw new ArgumentOutOfRangeException(nameof(startRegister));
-
-        StartRegister = (UInt16)start;
+        Words         = words;
+        StartRegister = startRegister;
     }
 
     public IEnumerator<UInt16> GetEnumerator() => Words.GetEnumerator();
@@ -74,9 +62,6 @@ public struct MbRegisters : IReadOnlyList<UInt16>
         var hi = (UInt32) GetUInt16(i);
         var lo = (UInt32) GetUInt16(++i);
 
-        if (Endianness == LittleEndian)
-            (lo, hi) = (hi, lo);
-
         return hi << 16 | lo;
     }