ID 210C: Introduction to CAN/LIN Solutions Renesas Electronics America Inc. Sridhar Lingam Product Marketing Manager 12 October 2010 Version 10
Dec 24, 2015
ID 210C: Introduction to CAN/LIN Solutions
Renesas Electronics America Inc.
Sridhar Lingam
Product Marketing Manager
12 October 2010
Version 10
2
Sridhar Lingam
Product Marketing Manager Renesas MCU CAN Solutions M16C/R32C, H8S/H8SX Product Families TFT-LCD solution for H8S and H8SX
Education MSEE from the Clemson University, Clemson, SC
Work Experience 16 years experience with semiconductor Industry with focus on
Industrial applications Varied experience as Product Engineer, FAE and Product
Marketing Responsible for definition and Marketing of Memory & MCU
product families Previously worked at National Semiconductor,
STMicroelectronics & Atmel
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Renesas Technology and Solution Portfolio
Microcontrollers& Microprocessors
#1 Market shareworldwide *
Analog andPower Devices#1 Market share
in low-voltageMOSFET**
Solutionsfor
Innovation
Solutionsfor
InnovationASIC, ASSP& Memory
Advanced and proven technologies
* MCU: 31% revenue basis from Gartner "Semiconductor Applications Worldwide Annual Market Share: Database" 25 March 2010
** Power MOSFET: 17.1% on unit basis from Marketing Eye 2009 (17.1% on unit basis).
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Renesas Technology and Solution Portfolio
Microcontrollers& Microprocessors
#1 Market shareworldwide *
Analog andPower Devices#1 Market share
in low-voltageMOSFET**
ASIC, ASSP& Memory
Advanced and proven technologies
* MCU: 31% revenue basis from Gartner "Semiconductor Applications Worldwide Annual Market Share: Database" 25 March 2010
** Power MOSFET: 17.1% on unit basis from Marketing Eye 2009 (17.1% on unit basis).
Solutionsfor
Innovation
Solutionsfor
Innovation
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Microcontroller and Microprocessor Line-up
Superscalar, MMU, Multimedia Up to 1200 DMIPS, 45, 65 & 90nm process Video and audio processing on Linux Server, Industrial & Automotive
Up to 500 DMIPS, 150 & 90nm process 600uA/MHz, 1.5 uA standby Medical, Automotive & Industrial
Legacy Cores Next-generation migration to RX
High Performance CPU, FPU, DSC
Embedded Security
Up to 10 DMIPS, 130nm process350 uA/MHz, 1uA standbyCapacitive touch
Up to 25 DMIPS, 150nm process190 uA/MHz, 0.3uA standbyApplication-specific integration
Up to 25 DMIPS, 180, 90nm process 1mA/MHz, 100uA standby Crypto engine, Hardware security
Up to 165 DMIPS, 90nm process 500uA/MHz, 2.5 uA standby Ethernet, CAN, USB, Motor Control, TFT Display
High Performance CPU, Low Power
Ultra Low PowerGeneral Purpose
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Microcontroller and Microprocessor Line-up
Superscalar, MMU, Multimedia Up to 1200 DMIPS, 45, 65 & 90nm process Video and audio processing on Linux Server, Industrial & Automotive
Up to 500 DMIPS, 150 & 90nm process 600uA/MHz, 1.5 uA standby Medical, Automotive & Industrial
Legacy Cores Next-generation migration to RX
High Performance CPU, FPU, DSC
Embedded Security
Up to 10 DMIPS, 130nm process350 uA/MHz, 1uA standbyCapacitive touch
Up to 25 DMIPS, 150nm process190 uA/MHz, 0.3uA standbyApplication-specific integration
Up to 25 DMIPS, 180, 90nm process 1mA/MHz, 100uA standby Crypto engine, Hardware security
Up to 165 DMIPS, 90nm process 500uA/MHz, 2.5 uA standby Ethernet, CAN, USB, Motor Control, TFT Display
High Performance CPU, Low Power
Ultra Low PowerGeneral Purpose
CAN MCU Solutions
R8C/R32C/SH/RX
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Innovation
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Our CAN/LIN Solution
Renesas’ easy to design MCU CAN/LIN solutions provide highly reliable, expandable, and noise immune
interfaces for industrial applications using chip to chip communications.
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Agenda
CAN in Embedded Networks
What is CAN & it’s benefits?
Can Basics
What is LIN and it’s benefits?
Renesas MCU CAN Solutions
Q&A
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Key Takeaways
Reasons for using CAN and LIN
Benefits of CAN and LIN
Basics of CAN and LIN
General differences between CAN and LIN
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What is CAN ?
Controller – Area – Network
Developed in 1983 by Robert Bosch
To solve the networking issues in automotive
Main Benefits
Economical
Reliable
Real Time response
Scalable
Standards
CAN 2.0A (ISO11519)
Can 2.0B(ISO11898)
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CAN-Leading Choice for Embedded Networking
The main Reasons are Economical
– Low Wiring Cost
– Low Hardware Cost
Reliability
– Error Free Communication
– Immune to EMI/EMS
Availability
– Several 8/16/32 bit MCU available in the market
– Standard development tools
Scalability
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Question
Please give 3 reasons for the growing popularity of
CAN in embedded applications
Reliability (works well in noisy environment)
Economical ( Have low wiring costs)
Scalability
Availability
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Features and Benefits of CAN
Multiple Master Hierarchy
1 Mbps of Data transfer rate
0-8 Bytes of User Data
Unique mail box Identifiers
Acceptance Filtering by nodes
Provides Error Detection
Fault Confinement measures
Auto re-transmit if corrupted
Redundant Intelligent Systems
Real Time Response
Simplifies design requirements
Flexibility in System Design
Arbitration & Prioritization
Ensures high Reliability
Keeps the traffic undisturbed
Accurate communication link
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CAN and the 7-layer model
1. Physical Layer
2. Data Link Layer
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer
Standard CAN implementation
Partially implemented by higher-level CAN protocols (CANOpen)
ISA/OSI Reference Model
Managed in Hardware.
Dramatic Real-time advantage to
System Design
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Data Flow in CAN
Transmitting Node
MCU Firmware
Identifier [id_n]
Data [values_x]
CAN Peripheral
Tx Mail Box [id_n]
Data [values_x]
Rx Mail Box [id_c]
Rx Mail Box [id_b]
CAN Transceiver
Node Configured to
receive identifier
MCU Firmware
Identifier [id_n]
Data [values_x]
CAN Peripheral
Data [values_x]
CAN Transceiver
Rx Mail Box [id_c]
Rx Mail Box [id_b]
Rx Mail Box [id_n]
Node not Configured to
receive identifier
MCU Firmware
CAN Peripheral
CAN Transceiver
Rx Mail Box [id_d]
Rx Mail Box [id_b]
Rx Mail Box [id_c]
Rx Mail Box [id_a]
Data Frame is broadcast to the bus ][value ]id n_[ x_
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Start of Frame – 1-bit
Arbitration Field – 11-bits/29-bits
Control Field – 6 bits (2 reserved, 4 representing number of Data Field bytes)
Data Field – 0 to 8 BYTES
CRC – 15-bits
ACK Field – 1-bit/variable
End of Frame – 7-bits (recessive)
Data Frame
SOF
1
Identifier
11/29
ID exten
d 1
Rem
Req
1
EOF
7+
Data(Bytes)
0-8 bytes
CRC
15
ACK
1
Control
4
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Question
Why do most CAN applications use CAN 2.0A (11-bit
identifiers) and not CAN 2.0B (29-bit identifiers)?
Overall data bandwidth decreases
Decrease in reliability
Increase in worse case delay
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CAN Bus Characteristics
Dominant bits (0’s) override recessive bits (1’s) on the CAN bus.
100
101
000
Node 1
Node 2
Node 3
000
Node 2 Backs Off
Node 1 Backs Off
LSB…MSB
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Maintaining Synchronization
‘Bit Stuffing’ is applied to keep the bus synchronized Five bits of consecutive dominant or recessive bits inserts a bit
of the opposite polarity Resulting signal edge is used to establish timing synchronization
at all nodes Stuffed bits are managed by hardware
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Bus Access and Arbitration
The CAN protocol handles bus accesses according to the concept of “Carrier Sense Multiple Access with Collision Detection”
For a collision, messages are NOT destroyed!No bandwidth is wasted on collisions! The message with the higher priority wins bus access
– NDA – “Non-destructive Arbitration”
Each message has an identifier that determines the priority Each node defined by unique identifier to avoid collisions
AMP – “Arbitration by Message Priority”
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CAN and EMI
CAN-Bus(Differential Serial Bus)
CAN_L
CAN_H
EMI
V
t
Node CNode A Node B
U diff
CAN_H
CAN_L
(dominant level)
+ - + -
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CAN Baud Rate vs. Bus Length
Bus lines assumed to be
an electrical medium
(e.g. twisted pair)
40 100 1000 10,000
CAN Bus Length [m]0 10 200
1000500
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Bit Rate
[kbps]20
50
200
100
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Error Detection in CAN
Error statistics depend up on the entire environment
Total number of nodes
Physical Layout
EMI Disturbance
CAN application example running at
2000 hours/year, 500 Kbps, 25% Bus load
Results in one undetected error in 1000 years
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Physical Layer
OpticalTransceiver
CAN_Txd
CAN_RxdOptical Fiber
CAN_Txd
CAN_RxdCA
NC
on
tro
ller
DifferentialTransceiver
CAN_Txd
CAN_Rxd
Physical CAN Bus(Differential, e.g Twisted Pair)
Physical CAN Bus(Differential, e.g Twisted Pair)
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Cables and Connectors
CAN does not specify the physical media
Common Wire Twisted pair Shielded twisted pair If optional power is needed: additional twisted pair
– A pair of “shielded twisted pair” Application specific
Common Connector 9-pin Dsub 5-pin mini style Terminal blocks Application specific (e.g. telephone jacks)
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What is LIN ?
Local Interconnect Network
A slower & low cost alternative to CAN
Developed by LIN Consortium in 2002
Developed as a sub-network of CAN to reduce the Bus Load
Applications
Automotive, White Goods, Medical – for sensors and actuators
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Features & Benefits of LIN
Complementary to CAN
Single Wire Implementation
Speed up to 20Kbps
Single Master/Multiple Slave
Based on common UART/SCI
Self Synchronization
Guaranteed latency times
Extends CAN to sub-nets
Reduce harness costs
Improves EMI response
No arbitration necessary
Reduces risk of availability
No external crystal
Deterministic & Predictable
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Typical LIN Network
ECU & Gateway
CAN
SCILIN phys IF
CANphys
IF
5V
Node A
SCI
Node B
XCVRSCI
XCVR
Node C
SCIXCVR
Node D
SCIXCVR
Simplex12V Operation
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LIN Message Frame
0 to 8 data fields checksum
message response
synch break 13 bit
synch field identifier
message header
Synchronization
Frame
Synchronization
Field
Identifier Byte Message
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LIN Physical Interface
VBAT8...18V
GND
recessivelogic ‘1’
dominantlogic ‘0’
60%
40%
Bus Voltage
Time
UARTRx
Tx
LIN Control Unit
master: 1kslave: 30k
Buscontrolled slope~2V/µs
Example capacitancesmaster: 2.2nFslave: 220pF
Usually managed by a
transceiver
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Taking account of Ground-Shift
Data timing
Sen
se v
olta
ge
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LIN Baud Rate Requirements
(1)The pre-synchronization accuracy in rev. 1.3 is ±15%, but this is
tightened to 14% in LIN 2.0
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Question
What are the reasons when LIN is preferred over CAN?
To save the bandwidth of another main bus
Size of Network is 16 nodes or less
When lower speed is acceptable
Economical
Single Master with multiple slaves
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LIN versus CAN
LIN versus CAN
Access Control Single Master Multiple Master
Max Bus Speed 20 Kbps 1 Mbps
Typical # nodes 2 to 16 4 to 20
Message Routing 6-bit Identifier 11/29-bit Identifier
Data byte/frame 2,4,8 bytes 0-8 bytes
Error detection 8-bit checksum 16-bit CRC
Physical Layer Single-wire Twisted-pair
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Renesas CAN/LIN Solutions
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Renesas MCU CAN Solutions
SH7216200MHz@3/5V
RX600100MHz@3V SH7264/62
144MHz@3V
New
SH7286100MHz@3/5V
R32C/117With FPU
64MHz@3/5V
R32C/118With FPU
64MHz@3/5V
R8C/2x20MHz@3/5V
M16C/2920MHz@3/5V
Single
CANMulti
CAN
Low End
Up to 128 KB Flash
1 CAN
48-64 pin
High End
Up to 1 MB Flash
1-2 CAN
176 pin
Mid End
Up to 1 MB Flash
1-2 CAN
100/144/176 pin
CAN API
Compatible
www.america.renesas.com/CAN
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Implementation of CAN in Renesas MCU
Common Control/Status
Registers
CAN 2.0A / CAN 2.0BProtocol Engine
CPUInterface
Message Buffer
AcceptanceFilter
Control Registers
16/32 Message Buffers
Up to 1Mbps data rate
INTs
Clock
Data
Control
RX
TX
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Renesas M16C LIN Roadmap
M16C/Tiny
M32C
R8C/3x
M16C
R32C
Common LIN API
Support for all
M16C ProductsUART LIN
Dedicated LIN
Hardware
M1
6C
Pla
tfo
rm
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CAN Development Kits for R8C & R32C– CAN-D Kit Two R8C/23 or R32C/118 Renesas Starter Boards Systec CAN protocol Analyzer included in the kit E8/E30a Debug Interface Up to 3 CAN interfaces with 32 mailboxes each Time-triggered CAN support All board specific APIs and drivers available in included CD Extensive third-party middleware support available Sample projects and
evaluation software– CAN API– LIN API
Renesas CAN Development Kit
RCDK8C (R8C), MSRP: $495
YRCDK32C (R32C), MSRP: $550
R32C CAN-D kit now available
Common API for all Renesas CAN MCU Solutions
www.america.renesas.com/CAN
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Innovation
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Questions?
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Feedback Form
Please fill out the feedback form! If you do not have one, please raise your hand
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Thank You!
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Appendix
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Serial Communications
CAN, LIN, RS-485, RS-232, SPI, I2C, etc. are all serial communications
Advantages No line-to-line timing skew Fewer wires lowering cable, connector, and design costs Saves on board space and power consumption per bit
Disadvantages Generally point-to-point Overhead above actual data payload that uses bandwidth Higher signal rates shorten transmission distances
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Transmission Topologies
Point-to-Point (Simplex) One transmitter and one receiver per line Transmission is possible only in one direction, i.e. unidirectional.
Multidrop (Distributed Simplex) point-to-point configuration with one transmitter and many
receivers Only unidirectional transfer is possible.
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Transmission Topologies
Multipoint (Multiplex) Many transmitters and many receivers per line. Transmission is possible in either direction, i.e. bidirectional.
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Number of CAN Nodes Built
0
100
200
300
400
500
600
700
800
Millions
1998 2000 2002 2004 2006 2008 2010
Year
CAN Nodes Built
Millions of Units
~Over 2 Billion Nodes Shipped YTD!!!*
Source: CiA (CAN-in-Automation): http://www.can-cia.org*; REA estimates
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A Typical 2-channel CAN Solution2-channel CAN MCU
CPU
CAN CAN
CAN Transceiver
CAN Transceiver
Lighting System
Motion Sensor
Temp Sensor
Motor Control
HVAC
Monitor
CAN Bus 1Low-Speed
CAN Bus 2High-Speed
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RS-485 vs. CAN
CAN equals RS-485? Similar costs Similar distances Similar electrical immunity Similar chip availability Similar connectors Same 32 nodes (loads) standard Duplex (4 wire) or Half-Duplex (2 wire) options available
RS-485 is used primarily due to Legacy.Remember 8051?
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2. Data Link Layer
RS-485 and the 7-layer model
1. Physical Layer
3. Network Layer
4. Transport Layer
5. Session Layer
6. Presentation Layer
7. Application Layer
Only Low Layer specification
Standard RS-485 implementation
Partially implemented by higher-level RS-485 protocols (i.e. MODBUS)
ISA/OSI Reference Model
Managed by CPU in Software
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CAN Protocol Versions
Two CAN protocol versions are available:
V2.0A (Standard) - 11 bit Message ID’s - 2048 ID’s available
V2.0B (Extended) - 29 bit Message ID’s - more than 536 Million ID’s available
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Termination Settings
High-Speed CAN (125Kbps+) For High-Speed CAN, both ends of the pair of signal wires (CAN_H and
CAN_L) must be terminated ISO 11898 requires a cable with a nominal impedance of 120 ohms
– 120 ohm resistors should be used for termination Only the devices on the ends of the cable need termination resistors
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Termination Settings
Low-Speed CAN (Up to 125Kbps) Each device on the network needs a termination resistor for each data
line: R(RTH) for CAN_H and R(RTL) for CAN_L Requires termination on the transceiver rather than on the cable The resistance of each resistor is calculated through several formulas
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An example of LIN Implementation
Renesas Electronics America Inc.