The document discusses various types of computer networks and communication protocols. It describes client-server models, local area networks (LANs), and different network topologies like ring, star, and bus. It also covers the OSI model layers and different protocols like Ethernet, CANbus, RS-232, and CANopen. CANbus uses a bus topology and the CAN protocol for reliable communication between nodes. CANopen builds on CANbus and defines object dictionaries, message types, and services for device configuration and data exchange.

1. Embedded
Networks
Gökhan URUL

2. Computer Networks
• Client/Server Model
• File server A computer that stores and manages files for multiple users on a
network
• Web server A computer dedicated to responding to requests (from the browser
client) for web pages
• Local-area network (LAN) A network that connects a relatively small number of
machines in a relatively close geographical area

3. Types of Networks
• Ring topology A configuration that
connects all nodes in a closed loop on
which messages travel in one direction
• Star topology A configuration that
centers around one node to which all
others are connected and through which
all messages are sent
• Bus topology All nodes are connected to
a single communication line that carries
messages in both directions
• Ethernet
• CANBus

4. OSI Layer
Upper Layers
Lower Layers
Middle Layer
7. Application
6. Presentation
5. Session
4. Transport
3. Network
2. Data Link
1. Physical
• Open Systems
Interconnection (OSI)

5. OSI Katmanı

6. OSI Layer
7. Application
6. Presentation
1. Physical
Node A
Data Out
Data In
To/from
Node B

7. Layer Mimarisi ve Gerçek Haberleşme
7. Application
1. Physical
7. Application
1.Physical
Node a Node b

8. Layer Mimarisi ve Sanal Haberleşme
7. Application
3. Network
7. Application
3. Network

9. Wireshark

10. RS232 Seri Haberleşme
• Bilgisayar ve çevre birimleri
• Askeri birimlerde çoğunlukla
• Eski bir teknoloji
• Çeşitli hızlarda 9600, 115200 Baudrate
• Haberleşme çeşidi: Stream byte
• Windows üzerinde ortak
•

11. RS422/485 Seri Haberleşme
• Bilgisayar ve çevre birimleri
• Askeri birimlerde çoğunlukla
• Çeşitli hızlarda 9600, 115200, 968000
Baudrate(bit/second)
• Haberleşme çeşidi: Stream byte
• Windows üzerinde ortak

12. RS232 – RS422 Seri Haberleşme
Programlama
• http://www.codeproject.com/Articles/678025/Serial-Comms-in-Csharp-for-Beginners
public static void Write()
{
_serialPort. Write(0x65);
}
public static void Read()
{
while (_continue)
{
try
{
string message = _serialPort.ReadExisting();
Console.WriteLine(message);
}
catch (TimeoutException) { }
}
}
using System.IO.Ports;
public class PortChat
{
static SerialPort _serialPort;
public static void Main()
{
_serialPort = new SerialPort();
// Seri kanal özellikleri ayarlanır.
_serialPort.PortName = SetPortName(“COM1”);
_serialPort.BaudRate = SetPortBaudRate(“9600”);
_serialPort.Parity = SetPortParity(“NONE”);
_serialPort.DataBits = SetPortDataBits(“8”);
_serialPort.StopBits = SetPortStopBits(“1”);
// Geçerlilik süreleri ayarlanır.
_serialPort.ReadTimeout = 500;
_serialPort.WriteTimeout = 500;
_serialPort.Open();
readThread.Start();
}
}

13. CANBus Haberleşme
• Bus topology
• The CAN protocol uses a modified
version of the Carrier Sense Multiple
Access/Collision Avoidance
(CSMA/CA) technique used on
Ethernet

14. CANBus Haberleşme
• Uses a single terminated twisted pair cable
• Is multi master
• Maximum Signal frequency used is 1 Mbit/sec
• Length is typically 40M at 1Mbit/sec up to 10KM at
5Kbits/sec
• Has high reliability with extensive error checking
• Typical maximum data rate achievable is 40KBytes/sec
• Maximum latency of high priority message <120 µsec at
1Mbit/sec

15. CANBus Haberleşme Yöntemi
• Start of frame (SOF)
• Message Identifier (MID) the Lower the value the Higher the priority of the message
its length is either 11 or 29 bits long depending on the standard being used
• Remote Transmission Request (RTR) = 0 ----- see "Remote Frames" para below for non
zero value
• Control field (CONTROL) this specifies the number of bytes of data to follow (0-8)
• Data Field (DATA) length 0 to 8 bytes
• CRC field containing a fifteen bit cyclic redundancy check code
• Acknowledge field (ACK) an empty slot which will be filled by any and every node that
receives the frame
it does NOT say that the node you intended the data for got it, just that at least
one node on the whole network got it.
• End of Frame (EOF)

16. CANBus OSI Layer

17. CANBus Programming
• IXXAT
• Lawicel
Beschreibung VCI V2 VCI V3
Board selection
XAT_SelectHardware
XAT_EnumHwEntry
XAT_FindHwEntry
XAT_GetConfig
vciSelectDeviceDlg
vciEnumDeviceOpen
vciEnumDeviceNe xt
vciEnumDeviceClose
vciFindDeviceByHwid
vciFindDeviceByCla ss
Board initialization VCI2_PrepareBoard vciDeviceOpen
Board info VCI_ReadBoardInfo vciDeviceGetInfo
CAN controller
initialization
VCI_InitCan
canControlOpen
canControlInitialize
CAN message filter VCI_SetAccMask canControlSetAccFilter
CAN status VCI_ReadCanStatus canControlGetStatus
CAN channel
initialization
VCI_ConfigQueue(Tx)
VCI_ConfigQueue(Rx)
VCI_AssignRxQueO bj
canChannelOpen
canChannelInitialize
canChannelActivate
CAN channel status VCI_ReadQueStatus canChannelGetStatus
CAN controller start VCI_StartCan canControlStart
CAN message
transmission
VCI_TransmitObjVCI_R
equestObj
canChannelSendMessa
ge
and
canChannelPostMessag
e
CAN message
receiving
VCI_ReadQueObj
(Receive-Callbacks)
canChannelReadMessa
ge
or
canChannelWaitRxEven
t
canCha
nnelPeekMessage
Cancel board VCI_CancelBoard
canChannelClose
canControlClose
vciDeviceClose

18. CANOpen
• Özellikleri
• CANopen a subset from CAL (CAN Application Layer) developed by CiA!
• Auto configuration the network
• Easy access to all device parameters
• Device synchronization
• Cyclic and event-driven data transfer
• Synchronous reading or setting of inputs, outputs or parameters
• Uygulamalar
• Machine automatisation
• Avantajları
• Accommodating the integration of very small sensors and actuators
• Open and vendor independent
• Support s inter-operability of different devices
• High speed real-time capability

19. CANOpen
• Object Dictionary
• Message Types
• Service Data Objects (SDOs)
• Process Data Objects (PDOs)
• Network Management (NMT)
• Guarding and Heartbeats
• Emergency Messages

20. CANOpen

21. CANOpen / PDO , SDO,
• Types
• transfer PDOs (TPDOs)
• receive PDOs (RPDOs)
• Specs
• Event driven
• Sync based
• polling
• Time driven
• Detaylı CanOpen mesajlaşmaları için: CanOpen_Manual.pdf
• Canopen Basics: CANopen Seminar.pdf