diff --git a/S7.Net/COTP.cs b/S7.Net/COTP.cs
new file mode 100644
index 0000000..432cffc
--- /dev/null
+++ b/S7.Net/COTP.cs
@@ -0,0 +1,94 @@
+using System;
+using System.IO;
+using System.Net.Sockets;
+
+namespace S7.Net
+{
+
+ ///
+ /// COTP Protocol functions and types
+ ///
+ internal class COTP
+ {
+ ///
+ /// Describes a COTP TPDU (Transport protocol data unit)
+ ///
+ public class TPDU
+ {
+ public byte HeaderLength;
+ public byte PDUType;
+ public int TPDUNumber;
+ public byte[] Data;
+ public bool LastDataUnit;
+
+ public TPDU(TPKT tPKT)
+ {
+ var br = new BinaryReader(new MemoryStream(tPKT.Data));
+ HeaderLength = br.ReadByte();
+ if (HeaderLength >= 2)
+ {
+ PDUType = br.ReadByte();
+ if (PDUType == 0xf0) //DT Data
+ {
+ var flags = br.ReadByte();
+ TPDUNumber = flags & 0x7F;
+ LastDataUnit = (flags & 0x80) > 0;
+ Data = br.ReadBytes(tPKT.Length - HeaderLength - 4); //4 = TPKT Size
+ return;
+ }
+ //TODO: Handle other PDUTypes
+ }
+ Data = new byte[0];
+ }
+
+ ///
+ /// Reads COTP TPDU (Transport protocol data unit) from the network stream
+ /// See: https://tools.ietf.org/html/rfc905
+ ///
+ /// The socket to read from
+ /// COTP DPDU instance
+ public static TPDU Read(Socket socket)
+ {
+ var tpkt = TPKT.Read(socket);
+ return new TPDU(tpkt);
+ }
+
+ public override string ToString()
+ {
+ return string.Format("Length: {0} PDUType: {1} TPDUNumber: {2} Last: {3} Segment Data: {4}",
+ HeaderLength,
+ PDUType,
+ TPDUNumber,
+ LastDataUnit,
+ BitConverter.ToString(Data)
+ );
+ }
+
+ }
+
+ ///
+ /// Describes a COTP TSDU (Transport service data unit). One TSDU consist of 1 ore more TPDUs
+ ///
+ public class TSDU
+ {
+ ///
+ /// Reads the full COTP TSDU (Transport service data unit)
+ /// See: https://tools.ietf.org/html/rfc905
+ ///
+ /// Data in TSDU
+ public static byte[] Read(Socket socket)
+ {
+ var segment = TPDU.Read(socket);
+ var output = new MemoryStream(segment.Data.Length);
+ output.Write(segment.Data, 0, segment.Data.Length);
+
+ while (!segment.LastDataUnit)
+ {
+ segment = TPDU.Read(socket);
+ output.Write(segment.Data, (int)output.Position, segment.Data.Length);
+ }
+ return output.GetBuffer();
+ }
+ }
+ }
+}
diff --git a/S7.Net/PLC.cs b/S7.Net/PLC.cs
index 67ad57a..6d2c0fe 100644
--- a/S7.Net/PLC.cs
+++ b/S7.Net/PLC.cs
@@ -4,10 +4,8 @@ using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Net;
-using System.Net.NetworkInformation;
using System.Net.Sockets;
using S7.Net.Types;
-using Double = System.Double;
namespace S7.Net
@@ -41,6 +39,11 @@ namespace S7.Net
/// Slot of the CPU of the PLC
///
public Int16 Slot { get; private set; }
+
+ ///
+ /// Max PDU size this cpu supports
+ ///
+ public Int16 MaxPDUSize { get; private set; }
///
/// Returns true if a connection to the PLC can be established
@@ -160,7 +163,6 @@ namespace S7.Net
/// Returns ErrorCode.NoError if the connection was successful, otherwise check the ErrorCode
public ErrorCode Open()
{
- byte[] bReceive = new byte[256];
_mSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
_mSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReceiveTimeout, 1000);
@@ -171,11 +173,27 @@ namespace S7.Net
return LastErrorCode;
}
- try
+ try
{
- byte[] bSend1 = { 3, 0, 0, 22, 17, 224, 0, 0, 0, 46, 0, 193, 2, 1, 0, 194, 2, 3, 0, 192, 1, 9 };
+ byte[] bSend1 = { 3, 0, 0, 22, //TPKT
+ 17, //COTP Header Length
+ 224, //Connect Request
+ 0, 0, //Destination Reference
+ 0, 46, //Source Reference
+ 0, //Flags
+ 193, //Parameter Code (src-tasp)
+ 2, //Parameter Length
+ 1, 0, //Source TASP
+ 194, //Parameter Code (dst-tasp)
+ 2, //Parameter Length
+ 3, 0, //Destination TASP
+ 192, //Parameter Code (tpdu-size)
+ 1, //Parameter Length
+ 9 //TPDU Size (2^9 = 512)
+ };
- switch (CPU) {
+ switch (CPU)
+ {
case CpuType.S7200:
//S7200: Chr(193) & Chr(2) & Chr(16) & Chr(0) 'Eigener Tsap
bSend1[11] = 193;
@@ -229,28 +247,33 @@ namespace S7.Net
return ErrorCode.WrongCPU_Type;
}
+ //COTP Setup
_mSocket.Send(bSend1, 22, SocketFlags.None);
- if (_mSocket.Receive(bReceive, 22, SocketFlags.None) != 22)
+ var response = COTP.TPDU.Read(_mSocket);
+ if (response.PDUType != 0xd0) //Connect Confirm
{
throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
- }
+ }
+ //S7ComSetup
byte[] bsend2 = { 3, 0, 0, 25, 2, 240, 128, 50, 1, 0, 0, 255, 255, 0, 8, 0, 0, 240, 0, 0, 3, 0, 3, 1, 0 };
_mSocket.Send(bsend2, 25, SocketFlags.None);
- if (_mSocket.Receive(bReceive, 27, SocketFlags.None) != 27)
+ var s7data = COTP.TSDU.Read(_mSocket);
+ if (s7data.Length >= 2 && s7data[1] == 0x03) //Check for S7 Ack Data
{
- throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
- }
+ MaxPDUSize = (short)(s7data[18] * 256 + s7data[19]);
+ return ErrorCode.NoError;
+ }
+
+ throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
}
- catch(Exception exc)
+ catch (Exception exc)
{
LastErrorCode = ErrorCode.ConnectionError;
LastErrorString = string.Format("Couldn't establish the connection to {0}.\nMessage: {1}", IP, exc.Message);
return ErrorCode.ConnectionError;
}
-
- return ErrorCode.NoError;
}
///
@@ -276,11 +299,12 @@ namespace S7.Net
public void ReadMultipleVars(List dataItems)
{
int cntBytes = dataItems.Sum(dataItem => VarTypeToByteLength(dataItem.VarType, dataItem.Count));
-
- if (dataItems.Count > 20)
- throw new Exception("Too many vars requested");
- if (cntBytes > 222)
- throw new Exception("Too many bytes requested"); // TODO: proper TDU check + split in multiple requests
+
+ //Is this really a limit?
+ //if (dataItems.Count > 20)
+ // throw new Exception("Too many vars requested");
+ if (cntBytes > MaxPDUSize - 18)
+ throw new Exception(string.Format("Too many bytes requested Requested: {0} Max {1}", cntBytes, MaxPDUSize)); //TODO: split in multiple requests
try
{
@@ -296,12 +320,10 @@ namespace S7.Net
_mSocket.Send(package.array, package.array.Length, SocketFlags.None);
- byte[] bReceive = new byte[512];
- int numReceived = _mSocket.Receive(bReceive, 512, SocketFlags.None);
- if (bReceive[21] != 0xff)
- throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
+ var s7data = COTP.TSDU.Read(_mSocket);
+ if (s7data[14] != 0xff) throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
- int offset = 25;
+ int offset = 18;
foreach (var dataItem in dataItems)
{
int byteCnt = VarTypeToByteLength(dataItem.VarType, dataItem.Count);
@@ -309,7 +331,7 @@ namespace S7.Net
for (int i = 0; i < byteCnt; i++)
{
- bytes[i] = bReceive[i + offset];
+ bytes[i] = s7data[i + offset];
}
offset += byteCnt + 4;
@@ -344,7 +366,7 @@ namespace S7.Net
int index = startByteAdr;
while (count > 0)
{
- var maxToRead = (int)Math.Min(count, 200);
+ var maxToRead = (int)Math.Min(count, MaxPDUSize);
byte[] bytes = ReadBytesWithASingleRequest(dataType, db, index, maxToRead);
if (bytes == null)
return resultBytes.ToArray();
@@ -622,7 +644,7 @@ namespace S7.Net
int count = value.Length;
while (count > 0)
{
- var maxToWrite = (int)Math.Min(count, 200);
+ var maxToWrite = (int)Math.Min(count, MaxPDUSize);
ErrorCode lastError = WriteBytesWithASingleRequest(dataType, db, startByteAdr + localIndex, value.Skip(localIndex).Take(maxToWrite).ToArray());
if (lastError != ErrorCode.NoError)
{
@@ -731,7 +753,7 @@ namespace S7.Net
package = Types.DWord.ToByteArray((UInt32)value);
break;
case "Double":
- package = Types.Double.ToByteArray((Double)value);
+ package = Types.Double.ToByteArray((double)value);
break;
case "Byte[]":
package = (byte[])value;
@@ -815,10 +837,12 @@ namespace S7.Net
{
return Write(DataType.DataBlock, mDB, dbIndex, (Int32)value);
}
- else
+ else if (value is double)
{
- objValue = Convert.ChangeType(value, typeof(UInt32));
+ return Write(DataType.DataBlock, mDB, dbIndex, value);
}
+
+ objValue = Convert.ChangeType(value, typeof(UInt32));
return Write(DataType.DataBlock, mDB, dbIndex, (UInt32)objValue);
case "DBX":
mByte = dbIndex;
@@ -1047,13 +1071,12 @@ namespace S7.Net
_mSocket.Send(package.array, package.array.Length, SocketFlags.None);
- byte[] bReceive = new byte[512];
- int numReceived = _mSocket.Receive(bReceive, 512, SocketFlags.None);
- if (bReceive[21] != 0xff)
+ var s7data = COTP.TSDU.Read(_mSocket);
+ if (s7data[14] != 0xff)
throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
for (int cnt = 0; cnt < count; cnt++)
- bytes[cnt] = bReceive[cnt + 25];
+ bytes[cnt] = s7data[cnt + 25];
return bytes;
}
@@ -1113,8 +1136,8 @@ namespace S7.Net
_mSocket.Send(package.array, package.array.Length, SocketFlags.None);
- int numReceived = _mSocket.Receive(bReceive, 512, SocketFlags.None);
- if (bReceive[21] != 0xff)
+ var s7data = COTP.TSDU.Read(_mSocket);
+ if (s7data[14] != 0xff)
{
throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
}
@@ -1163,11 +1186,9 @@ namespace S7.Net
_mSocket.Send(package.array, package.array.Length, SocketFlags.None);
- int numReceived = _mSocket.Receive(bReceive, 512, SocketFlags.None);
- if (bReceive[21] != 0xff)
- {
+ var s7data = COTP.TSDU.Read(_mSocket);
+ if (bReceive[14] != 0xff)
throw new Exception(ErrorCode.WrongNumberReceivedBytes.ToString());
- }
return ErrorCode.NoError;
}
diff --git a/S7.Net/S7.Net.csproj b/S7.Net/S7.Net.csproj
index ac2ac19..bb2abab 100644
--- a/S7.Net/S7.Net.csproj
+++ b/S7.Net/S7.Net.csproj
@@ -77,9 +77,11 @@
+
+
diff --git a/S7.Net/TPKT.cs b/S7.Net/TPKT.cs
new file mode 100644
index 0000000..f5a4aab
--- /dev/null
+++ b/S7.Net/TPKT.cs
@@ -0,0 +1,46 @@
+using System;
+using System.Net.Sockets;
+
+namespace S7.Net
+{
+
+ ///
+ /// Describes a TPKT Packet
+ ///
+ internal class TPKT
+ {
+ public byte Version;
+ public byte Reserved1;
+ public int Length;
+ public byte[] Data;
+
+ ///
+ /// Reds a TPKT from the socket
+ ///
+ /// The socket to read from
+ /// TPKT Instace
+ public static TPKT Read(Socket socket)
+ {
+ var buf = new byte[4];
+ socket.Receive(buf, 4, SocketFlags.None);
+ var pkt = new TPKT
+ {
+ Version = buf[0],
+ Reserved1 = buf[1],
+ Length = buf[2] * 256 + buf[3] //BigEndian
+ };
+ pkt.Data = new byte[pkt.Length - 4];
+ socket.Receive(pkt.Data, pkt.Length - 4, SocketFlags.None);
+ return pkt;
+ }
+
+ public override string ToString()
+ {
+ return string.Format("Version: {0} Length: {1} Data: {2}",
+ Version,
+ Length,
+ BitConverter.ToString(Data)
+ );
+ }
+ }
+}