CA

N

© CiA

Node 2 Node 2 Node 3 Node 3 Node 4 Node 4

Node n Node n Node 1 Node 1 Ld

Ld = Drop Length

Lt

Lt = Trunk Length

ISO 11898-2 Topology

CA

N

© CiA

node 1 . . . . . . . . node n

CAN Bus Line

120

CAN_H

CAN_L

120

ISO 11898-2 Network Set-up

CA

N

© CiA

EMI

CAN Bus Line 120 120

CAN_H

CAN_L

t

V

Vdiff = const

Vdiff

Electromagnetic Interference

CA

N

© CiA

Time

Voltage

5 V

3.5 V

2.5 V

1.5 V

0 V

min. 1 µs

Recessive

CAN_H + CAN_L

CAN_H

CAN_L

Dominant Recessive

Nominal Bus Level

CA

N

© CiA

CANStation 1

(Consumer)

CANStation 2

(Producer)

CANStation 3

(Consumer)

CANStation 4

(Consumer)

Frame I

LocalIntelligence

LocalIntelligence

LocalIntelligence

LocalIntelligence

bus lines

FilterFilter Filter Filter

Broadcast Communication

CA

N

© CiA

CANStation 1

(Requester)

CANStation 2

(Producer)

CANStation 3

(Consumer)

CANStation 4

(Consumer)

LocalIntelligence

LocalIntelligence

LocalIntelligence

LocalIntelligence

bus lines

FilterFilter Filter FilterRTR I Frame I

Remote Request

CA

N

© CiA

CANStation 1

CANStation 2

CANStation 3

CANStation 4

LocalIntelligence

LocalIntelligence

LocalIntelligence

LocalIntelligence

bus lines

FilterFilter Filter FilterFrame I Frame 3Frame 2

Multiple Bus Access

CA

N

© CiA

SOF

BusIdle

ArbitrationField

DataField

CRCField

ACKField

EOF IFS

12 or 32 Bit 6 Bit 0 to 8 Byte 16 Bit 2 Bit 7 Bit1Bit 3 Bit

Remark: CAN Specification 2.0 B passive implementations can’t store or transmit Extended Data Frames; CAN Specification 2.0 B active implementations can store and transmit Standard Data Frames as well as Extended Data Frames.

ControlField

CAN Data Frame

CA

N

© CiA

SOF

BusIdle

ArbitrationField

CRCField

ACKField

Inter-Mission

12 or 32 Bit 6 Bit 16 Bit 2 Bit 7 Bit1 Bit 3 Bit

ControlField

EOF

CAN controller with receive buffer or receive FIFOs answers Remote Frames only under CPU control.

CAN Controller with standard message storing answers Remote Frame automatically without CPU control.

CAN Controller with advanced message storing answers Remote Frames automatically and optionally under CPU

control.

CAN Remote Frame

CA

N

© CiA

Base Frame Format

11 bit Identifier RTR IDE r0 DLC SOF

Arbitration Field Control Field Data Field

Extended Frame Format

SOF

Arbitration Field Control Field

11 bit Identifier SRR IDE 18 bit Identifier RTR r1 r0 DLC

Trade-off: longer bus latency time (20 bit-times)longer frames (20 bit-times plus stuff-bits)reduced CRC performance

Arbitration Field

CA

N

© CiA

Node 1

Node 2

Node 3

Bus ID 20

ID 80

ID 20

Data

Data

ID 80 Data

ID 80 DataID 100 Data

ID 100 Data

Frame transmission request

Bus Arbitration Method

CA

N

© CiA

Bus (4 x Rx)

S RO Identifier T Control DataF 10 9 8 7 6 5 4 3 2 1 0 R Field Field

dominant

recessive

Listening Mode

Listening Mode

Collision Avoidance

DLC Data

Listening Mode

Node 1 (Tx)

Node 2 (Tx)

Node 3 (Tx)

Node 4 (Tx)

CA

N

© CiA

0 to 8 Byterequest

indication(s)

Producer Consumer(s)

CAN Data Frame

Write Object

confirmation(s)0 to 8 Byte

response

indication request(s)

CAN Remote Frame

CAN Data Frame

Read Object

Communication Services

CA

N

© CiA

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 [km]

1.00.90.80.70.60.50.40.30.20.1

1.6

[Mbit/s]

Data-rate/Bus-length Ratio

CA

N

© CiA

Bit Rate

1 Mbit/s800 kbit/s500 kbit/s250 kbit/s125 kbit/s

62.5 kbit/s 20 kbit/s10 kbit/s

Bus Length

30 m50 m

100 m250 m500 m

1000 m2500 m5000 m

Nominal Bit-Time

1 µs1.25 µs

2 µs4 µs8 µs

20 µs50 µs

100 µs

Practical Bus Length

CA

N

© CiA

DC Parameter• Length-Related Resistance (r): 70 m /m• Termination Resistor (Rt): nominal 120 (min. 108 , max. 132 )

AC Parameter• Impedance (Z): nominal 120 (min. 108 , max. 132 )•Specific Line Delay: 5 ns/m

ISO11898-2 Parameter

CA

N

© CiA

BusLength

BusLength

0 .. 40 m0 .. 40 m

40 .. 300 m40 .. 300 m

300 .. 600 m300 .. 600 m

600 m .. 1 km600 m .. 1 km

Bus CableBus Cable

Length-Related

Resistance

Length-Related

ResistanceBus-Line

Cross-Section

Bus-LineCross-Section

70 m/m70 m/m 0.25 mm2 .. 0.34 mm2

AWG23, AWG22

0.25 mm2 .. 0.34 mm2

AWG23, AWG22

<60 m/m<60 m/m 0.34 mm2 .. 0.6 mm2

AWG22, AWG20

0.34 mm2 .. 0.6 mm2

AWG22, AWG20

<40 m/m<40 m/m 0.5 mm2 .. 0.6 mm2

AWG20

0.5 mm2 .. 0.6 mm2

AWG20

<26 m/m<26 m/m 0.75 mm2 .. 0.8 mm2

AWG 18

0.75 mm2 .. 0.8 mm2

AWG 18

TerminationResistance

TerminationResistance

124 (1%)124 (1%)

127 (1%)127 (1%)

150

150

150

150

Max.Baudrate

Max.Baudrate

1 Mbit/sat 40 m

1 Mbit/sat 40 m

500 Kbit/sat 100 m

500 Kbit/sat 100 m

100 Kbit/sat 500 m

100 Kbit/sat 500 m

50 Kbit/sat 1k m

50 Kbit/sat 1k m

DC Characteristics

CA

N

© CiA

Rules of thumb for the maximum length of a unterminated cable drop Ld and for for the cumulative drop length Ldi:

n

Ld < tPROPSEG / ( 50 * tP ) Ldi < tPROPSEG / ( 10 * tP ) i=1

tPROPSEG : length of the propagation segment of the bit period tP : specific line delay per length unit

Example: bit rate = 500 kbit/s: tPROPSEG = 12 * 125ns = 1500 ns; tP = 5 ns/m

n

Ld < 1500 ns / (50 * 5 ns/m) = 6 m; Ldi < 1500 ns /(10 * 5 ns/m) = 30 m i=1

Cable Drop Length

CA

N

© CiA

Bit rate

Bus length (1)

Nominal

bit time

tb

Number of

time quanta

per bit

Length of

time

quantum tq

Location of

sample

point

BTR 0

at 16 MHz

(82C200)

BTR 1

at 16 MHz

(82C200)

1 Mbit/s

25 m

1 µs 8 125 ns 6 tq

(750 ns)

00h 14h

800 kbit/s

50 m

1.25 µs 10 125 ns 8 tq

(1 µs)

00h 16h

500 kbit/s

100 m

2 µs 16 125 ns 14 tq

(1.75 µs)

00h 1Ch

250 kbit/s

250 m (2)

4 µs 16 250 ns 14 tq

(3.5 µs)

01h 1Ch

125 kbit/s

500 m (2)

8 µs 16 500 ns 14 tq

(7 µs)

03h 1Ch

50 kbit/s

1000 m (3)

20 µs 16 1.25 µs 14 tq

(17.5 µs)

09h 1Ch

20 kbit/s

2500 m (3)

50 µs 16 3.125 µs 14 tq

(43.75 µs)

18h 1Ch

10 kbit/s

5000 m (3)

100 µs 16 6.25 µs 14 tq

(87.5 µs)

31h 1Ch

CiA DS-102 Baudrate

CA

N

© CiA

Pin Signal Description 1 - Reserved 2 CAN_L CAN_L bus line dominant low 3 CAN_GND CAN Ground 4 - Reserved 5 (CAN_SHLD) Optional CAN Shield 6 GND Optional Ground 7 CAN_H CAN_H bus line dominant high 8 - Reserved 9 (CAN_V+) Optional CAN external supply

9-pin D-Sub: DIN 41652

CiA DS-102 Pin Assignment

CA

N

© CiA

31

203

273

355

120

2003

1998

2002

2000

2001

57 1999

40,502,60

18,77 102,10

120,82

14,45

37,07

59,20

10,10

57,77

10,70

25,70

141,50

45,47

15,20

203,27

71,95

171,80

92,48

15,30

273,82

15,70

355,58

75,6045,0732-bit µC

16-bit µC

stand-alone

8-bit µC

total in million units

2000 sales by regions:Europe: 85%America: 9%Asia: 6%

Application

CAN node sales figures

0

50

100

150

200

250

300

350

400 32-bit µC

16-bit µC

8-bit µC

stand-alone

1999 2000 2001 2002 2003

CA

N

© CiA

CAN-based ProfilesCAN-based Profiles

CAN-based Application LayerCAN-based Application Layer

Layers Implementation

Transceiver

CAN ControllerCAN Data Link LayerCAN Data Link Layer

CAN Physical LayerCAN Physical Layer

Software

Software

CAN Reference Model

CA

N

© CiA

CAN standardization

ISO 11898-1(11-bit ID)

ISO 11898-2

Data LinkLayer

PhysicalLayer

CAN 2.0A

RS-485

ISO 11898-1(11-bit ID)

ISO 11898-1(11-bit and29-bit ID)

ISO 11898-2

ApplicationLayer

SDSEN 50325-3

DeviceNetEN 50325-2

CANopenEN 50325-4

DeviceProfile

ODVADeviceProfiles

CiADeviceProfiles

ApplicationProfile

CiAApplication

Profiles

ISO 11898-2

ISO 11898-1(29-bit ID)

SAE J1939-based

ApplicationProfiles

CA

N

© CiA

CAN History Milestones

• 1982: Start of the Bosch-internal CAN development• 1986: First public presentation of CAN in Detroit at SAE conference• 1987: First CAN controller chip from Intel• 1990: Introduction of CAN Kingdom protocols• 1992: Foundation of CiA international users and manufacturers group• 1993: Publishing of ISO 11898 (CAN standard)• 1993: Introduction of CAN Application Layer (CAL)• 1993: Introduction of SAE J1939 application profile• 1994: 1st international CAN Conference in Mainz• 1994: Introduction of DeviceNet• 1994: Smart Distributed System (SDS)• 1994: Introduction of CANopen profile family• 1995: Foundation of ODVA• 2000: Foundation of CAN Kingdom International• 2001: Introduction of Time-triggered CAN (TTCAN) protocol• 2002: DeviceNet, SDS, and CANopen become European standards (EN50235)• 2003: ISO 11898-1 and ISO 11898-2 are published

CA

N

© CiA

CiA Operations Structure

Business Committee Managing Director Technical Committee

GENERAL ASSEMBLY

elects

CANopen

CANopen

USA

Russia

Benelux

CAL

approves and manages approves and manages

approves and manages

Inte

res

t G

rou

ps

Ma

rke

tin

g G

rou

ps

*

Progr.Devices

Safety Maritime MedicalTruck

Gateway

WeavingMachine

LiftControl

ElectronicDoor

PassengerInfo

IEC61131-3

GenericI/O

DriveVirtual

TerminalClosed-

Loop

EncoderASAM

Railways

Off-roadVehicles

Hydraulics

CA

No

pe

n S

pe

cia

l In

tere

st

Gro

up

s

* temporarily inactive

*

****

***

Municipalvehicles

TF BatteryTF Extruder

down-stream

TF Roadconstruct-

ion

CA

N

© CiA

CiA Members 1992-2003

1642

84

142

193250

284320 347

372 393 413

0

50

100

150

200

250

300

350

400

450

March'92

Jan'94

Jan'96

Jan'98

Jan'00

Jan'02

CA

N

© CiA

CiA Services• CANschool (technical training for newcomers) • CANopen seminar (technical training)• In-house seminars ( customer-specific training)• CANopen product guide (free-of-charge)• Quarterly CAN Newsletter (free-of-charge)• Review of proprietary CANopen profiles• CANopen device certification• CAN literature and specification sales