CAN (Controller Area Network) is a bus standard introduced in 1986 that defines protocols for microcontrollers and devices to communicate in applications without a host computer. It allows various electronic control units and devices to communicate with each other via a bus line. CAN was developed for use in automotive applications but is now also used in other fields like aerospace, maritime, and industrial automation. It provides robust messaging with efficient use of bandwidth and error detection.

1. CAN B S
Idea by
Ahmad
In The Name Of Allah
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2. History
The abbreviation “CAN” stands for
“Controller Area Network”.
This bus:
• Introduced by Robert Bosch in 1986.
• Developed for automotive applications
• Standardized in 1993 as ISO11898-1
• CAN Standards :
• CAN 2.0A
• CAN 2.0B
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3. BUS topology
 What is a Network Topology
 It is the arrangement of various elements [Links, Nodes,
Etc.] for a Network [a telecommunication n/w] to
exchange Data
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4. Car System4

5. Before CAN!
Windows Power
& Control
System :
Different
Speed
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6. After CAN!!!6

7. Serial vs. Parrallel
Why Serial Communication
A few advantages
 A serial connection requires fewer interconnecting cables (e.g.,
wires/ fibers) and hence occupies less space.
 The extra space allows for better isolation of the channel from its
surroundings.
 Serial is a better option because it is cheaper to implement
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8. CAN vs. MultiWire Network
 Physical medium – two wires terminated at both ends by resistors.
 Differential signal - better noise immunity.
 Benefits:
 Reduced weight, Reduced cost
 Fewer wires = Increased reliability
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9. CANBUS and the OSI Model9

10. Summary10

11. Basic Configuration11

12. Transmission Characteristics
 Up to 1 Mbit/sec.
 Common baud rates: 1 MHz, 500 KHz and 125 KHz
 All nodes – same baud rate
 Max length:120’ to 15000’ (rate dependent)
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13. Message Oriented Transmission
Protocol
 Each node – receiver & transmitter
 A sender of information transmits to all devices on the bus
 All nodes read message, then decide if it is relevant to them
 All nodes verify reception was error-free
 All nodes acknowledge reception
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14. Message Format14

15. Message Format15

16. A Programm
A message frame information :
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17. A Programm
Message
Information
Write
message
Read
message
Set
Write
buffer
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18. Bus Arbitration
 Arbitration – needed when multiple nodes try to transmit at the
same time
 Only one transmitter is allowed to transmit at a time.
 A node waits for bus to become idle
 Nodes with more important messages continue transmitting
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19. Bus Arbitration(2)
 Message importance is encoded in message ID.
Lower value = More important
 As a node transmits each bit, it verifies that it sees the same bit
value on the bus that it transmitted.
 A “0” on the bus wins over a “1” on the bus.
 Losing node stops transmitting, winner continues.
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20. Bus Arbitration(3)
 Wired AND
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21. Bus Levels according to ISO-IS 11898
Logic 1 Logic 0
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22. CAN and EMI22

23. A Basic CAN controller
Cheap CAN controller – CPU could get overrun with messages
even if it didn’t need them.
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24. Full CAN Controller
Hardware message filters sort & filter messages without interrupting CPU
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25. An Example
Caterpillar 797
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26. An Example(2)26

27. An Example(3)27

28. A CAN Controller Circuit
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CAN
Controller
& Host
Standard
CAN Port
CAN
Transiver

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31. Refrence
 NXP LPC176x5x User manual
 Ducati North America
 Pedro Campana Antenna Control Specialist
 Introduction to CANBUS : Marek Hajek
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