SharpModbus-RELEASE-1.0.5.0 Improved CRC endianess handling. Maintena…

…nce release. Does not add or break any functionality.

SharpModbus/ModbusHelper.cs

@@ -17,7 +17,7 @@ public static ushort CRC16(byte[] bytes, int offset, int count)
 						crc >>= 1;
 				}
 			}
-			return (ushort)((crc >> 8) & 0x00ff | (crc << 8) & 0xff00);
+			return crc;
 		}
 
 		public static byte EncodeBool(bool value)
@@ -108,13 +108,6 @@ public static byte Low(int value)
 		{
 			return (byte)((value >> 0) & 0xff);
 		}
-		/*
-		public static void Set(byte[] bytes, int offset, ushort value)
-		{
-			bytes[offset + 0] = (byte)((value >> 8) & 0xff);
-			bytes[offset + 1] = (byte)((value >> 0) & 0xff);
-		}
-		*/
 
 		public static ushort GetUShort(byte bh, byte bl)
 		{
@@ -132,6 +125,14 @@ public static ushort GetUShort(byte[] bytes, int offset)
 			);
 		}
 
+		public static ushort GetUShortLittleEndian(byte[] bytes, int offset)
+		{
+			return (ushort)(
+			    ((bytes[offset + 1] << 8) & 0xFF00)
+			    | (bytes[offset + 0] & 0xff)
+			);
+		}
+
 		public static void Copy(byte[] src, int srcOffset, byte[] dst, int dstOffset, int count)
 		{
 			for (var i = 0; i < count; i++)

SharpModbus/ModbusRTUProtocol.cs

@@ -13,7 +13,8 @@ public IModbusWrapper Parse(byte[] request, int offset)
 		{
 			var wrapped = ModbusParser.Parse(request, offset);
 			var crc = ModbusHelper.CRC16(request, offset, wrapped.RequestLength);
-			Assert.Equal(crc, ModbusHelper.GetUShort(request, offset + wrapped.RequestLength), "CRC mismatch {0:X} expected:{1:X}");
+			Assert.Equal(crc, ModbusHelper.GetUShortLittleEndian(request, offset + wrapped.RequestLength), 
+			             "CRC mismatch {0:X4} expected {1:X4}");
 			return new ModbusRTUWrapper(wrapped);
 		}
 	}

SharpModbus/ModbusRTUWrapper.cs

@@ -19,14 +19,15 @@ public void FillRequest(byte[] request, int offset)
 		{
 			wrapped.FillRequest(request, offset);
 			var crc = ModbusHelper.CRC16(request, offset, wrapped.RequestLength);
-			request[offset + wrapped.RequestLength + 0] = ModbusHelper.High(crc);
-			request[offset + wrapped.RequestLength + 1] = ModbusHelper.Low(crc);
+			request[offset + wrapped.RequestLength + 0] = ModbusHelper.Low(crc);
+			request[offset + wrapped.RequestLength + 1] = ModbusHelper.High(crc);
 		}
 
 		public object ParseResponse(byte[] response, int offset)
 		{
 			var crc1 = ModbusHelper.CRC16(response, offset, wrapped.ResponseLength);
-			var crc2 = ModbusHelper.GetUShort(response, offset + wrapped.ResponseLength);
+			//crc is little endian page 13 http://modbus.org/docs/Modbus_over_serial_line_V1_02.pdf
+			var crc2 = ModbusHelper.GetUShortLittleEndian(response, offset + wrapped.ResponseLength);
 			Assert.Equal(crc2, crc1, "CRC mismatch {0} {1}");
 			return wrapped.ParseResponse(response, offset);
 		}
@@ -40,8 +41,8 @@ public void FillResponse(byte[] response, int offset, object value)
 		{
 			wrapped.FillResponse(response, offset, value);
 			var crc = ModbusHelper.CRC16(response, offset, wrapped.ResponseLength);
-			response[offset + wrapped.ResponseLength + 0] = ModbusHelper.High(crc);
-			response[offset + wrapped.ResponseLength + 1] = ModbusHelper.Low(crc);
+			response[offset + wrapped.ResponseLength + 0] = ModbusHelper.Low(crc);
+			response[offset + wrapped.ResponseLength + 1] = ModbusHelper.High(crc);
 		}
 
 		public override string ToString()

SharpModbus/package.nuspec

@@ -2,7 +2,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2010/07/nuspec.xsd">
 	<metadata>
 		<id>SharpModbus</id>
-		<version>1.0.4.0</version>
+		<version>1.0.5.0</version>
 		<authors>Samuel Ventura</authors>
 		<description>C# Modbus Tools</description>
 		<projectUrl>https://github.com/samuelventura/SharpModbus</projectUrl>

SharpModbusTest/MasterTest.cs

@@ -1,4 +1,5 @@
 using System;
+using System.IO.Ports;
 using System.Net.Sockets;
 using System.Threading;
 using NUnit.Framework;
@@ -16,6 +17,30 @@ private bool[] Bools(int count, bool value)
 				bools[i] = value;
 			return bools;
 		}
+
+		[Test]
+		public void ModportSweepTest()
+		{
+			//m0 - MD-DIDC8 8 digital input
+			//m1 - MD-DOSO8 8 digital output
+			//all outputs wired to corresponding inputs
+			var serial = new SerialPort("COM10");
+			serial.BaudRate = 57600;
+			serial.Open();
+			var stream = new ModbusSerialStream(serial, 400);
+			var protocol = new ModbusRTUProtocol();
+			var master = new ModbusMaster(stream, protocol);
+
+			master.WriteCoil(1, 3000, false);
+			master.WriteCoil(1, 3001, true);
+			master.WriteCoil(1, 3002, true);
+			master.WriteCoil(1, 3003, false);
+			Thread.Sleep(50);
+			Assert.AreEqual(false, master.ReadCoil(1, 3000));
+			Assert.AreEqual(true, master.ReadCoil(1, 3001));
+			Thread.Sleep(50);
+			Assert.AreEqual(new bool[]{false, true, true, false}, master.ReadCoils(1, 3000, 4));
+		}
 
 		[Test]
 		public void RackSweepTest()

SharpModbusTest/SlaveTest.cs

@@ -9,7 +9,7 @@ namespace SharpModbusTest
 	public class SlaveTest
 	{
 		[Test]
-		public void RtuSlaveMethod()
+		public void RtuSlaveTest()
 		{
 			var model = new ModbusModel();
 			var stream = new ModelStream(model, new ModbusRTUScanner());
@@ -18,7 +18,7 @@ public void RtuSlaveMethod()
 		}
 
 		[Test]
-		public void TcpSlaveMethod()
+		public void TcpSlaveTest()
 		{
 			var model = new ModbusModel();
 			var stream = new ModelStream(model, new ModbusTCPScanner());