June, 2010 Automotive Networking Protocol Overview FTF-AUT-F0730 Peter Spindler Systems Engineer Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM Introduction ►This session (FTF-AUT-F0730) will cover FlexRay, a relatively new, deterministic, fault-tolerant and high-speed automotive network communications protocol under development by the FlexRay Consortium. It is designed to perform better and be faster and more reliable than CAN (Controller Area Network) and LIN (Local Interconnect Network). This session specifically covers: Overview of FlexRay • Version 3 of FlexRay • CAN & Ethernet – differences and extensions • ►Presenter: Peter Spindler, Systems Engineer ►Expertise: FlexRay, FlexRay Conformance Testing, Ethernet, Functional Safety ►This presentation is slated to last 1 hour. Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 2 Session Objectives ►After completion of this session, you will have a better understanding of: The basic concept of FlexRay • The new features of FlexRay V3.0 • The differentiation between FlexRay, CAN, and Ethernet • Some extensions of CAN and Ethernet • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 3 Agenda Outline: ►Part 1: Introduction to FlexRay ►Part 2: New features of FlexRay V3.0 ►Part 3: Other network protocols: CAN, Ethernet ►Summary Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 4 Part 1: Outline ►Part • • • • • 1: Introduction to FlexRay Overview Architecture Freescale Roadmap Access Scheme Time synchronization Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 5 FlexRay: Overview ►Communication system: physical layer + data link layer ►Developed by the FlexRay Consortium since 2000: Version 2.1: Publically available since 2005. • Version 3.0: Finalized. Publically available soon. • ►Time-triggered ►Main • • • • • communication protocol features: One or two communication channels Up to 10 Mbit/s per communication channel Deterministic behavior (i.e., predetermined message latency) Static and dynamic bandwidth allocation Fully configurable Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 6 Microcontroller ►CC: FlexRay Communication Controller: FlexRay: Architecture ►MCU: embedded (e) • standalone (s) • ►BD: FlexRay Bus Driver ►AS: FlexRay Active Star ►Cabling: twisted pair unshielded ►Two channels ►Topology: bus or star Node 1 Node 2 MCU MCU CC (e) CC (s) BD BD BD BD Bus Node x Node y AS AS Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. Node z Star TM 7 Application Performance / Integration FlexRay: Freescale Roadmap MPC567xF Single Core: z7, up to 264MHz Flash: 3M – 4M, RAM: up to 256K FlexRay Certificate MPC5567 130nm MPC5561 Advanced Driver Assistance & Safety Single core: z6, 80 – 132 MHz 130nm Flash: 512K – 1M, RAM: 98K – 192K MPC551XG Body Dual core: z0+z1, up to 80 MHz Flash: 512K – 1.5M, RAM: up to 80K 130nm Body, Powertrain, and Chassis Single Core: S12X, 50Mhz, XGATE Flash: 128K – 512K, RAM: 8K – 32K MFR4310 90nm Powertrain, Chassis Single core: z6, 80 – 132MHz Flash: 2M, RAM: 80K S12XF Powertrain, Chassis 0.18µ Body, Powertrain, and Chassis Standalone FlexRay Controller 0.25µ Gateways, Highly integrated body MPC5668G Dual Core: z0+z6, 116MHz 90nm Flash: 2M, RAM: 592K MPC564xL Chassis Dual Core: z4, 120MHz Flash: 512K – 1M, RAM: 64K – 128K MPC560xP Single Core: z0h, 64MHz Flash: 384K – 512K, RAM: 36K – 40K 90nm Chassis available 90nm planned now Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 8 FlexRay: Access Scheme Cycle i ... Static Dynamic Symbol NIT t Mini k Symbol NIT Mini 1 Mini 2 Mini 3 Mini 4 Mini 5 Mini 6 ... Dynamic Slot n Slot 3 Slot 2 Slot 1 Static Cycle i+1 Slot n+1 Slot n+2 Frame x Frame y ► Static Segment: Slots with fixed length. Fixed assignment between slots and nodes. Î Time division multiple access: TDMA ► Dynamic Segment: Minislots with fixed length. Minislots can be combined to contain frames with variable length. No fixed assigned between slots and nodes. ► Max. payload per frame (static and dynamic segment): 254 bytes ► Symbol Window: Used for wake-up symbols ► Network Idle Time (NIT): Clock correction Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 9 FlexRay: Clock Synchronization Node 1 Local clock CC 1 Node 3 CC 2 CC 3 ►Sync Static Slot 2 In each node • Offset and rate correction of local clock • Applied during Network Idle Time (NIT) • Cycle i Slot 1 frames (static segment) from configured sync nodes ►Based on the difference between expected and actual start time of each sync frame: Clock synchronization ►Clock synchronization: Node 2 s s Dynamic Symbol NIT … t Sync frame s t Real start time Expected start time Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 10 Part 2: Outline ►Part 2: New features of FlexRay V3.0 Various Enhancements • Dynamic Segment Robustness • New synchronization methods: TT-L, TT-E • Wake-up during operation • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 11 FlexRay V3.0: Enhancements (1/3) ►Slot • Multiplexing: Slot multiplexing: sharing of static communication slots between multiple nodes ►FIFO Buffer: At least one FIFO buffer is mandatory now. • Detailed FIFO filter criteria • ►Cycle Counter: Configurable cycle counter wraparound: any even number between 8 64 is possible • Extended cycle counter filtering: repetition values of 5, 10, 20, 40, and 50 • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 12 FlexRay V3.0: Enhancements (2/3) ►Timers • No relative timers anymore, but two absolute timers ►CHI • commands New CHI commands for “save shutdown” at the end of the communication cycle ►Individual • Reconfiguration of message buffers ►Network • management vector Network management vector is mandatory now ►Status • buffers data Number of received startup frames is provided to the host Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 13 FlexRay V3.0: Enhancements (3/3) ►Bit • rates Support for 2.5 Mbit/s, 5 Mbit/s, and 10 Mbit/s ►Dynamic Segment Ongoing transmission at the end of the dynamic segment no longer results in a fatal protocol error. • Automatic termination of a frame transmission in the dynamic segment if the dynamic segment ends before the frame transmission is complete (no fatal protocol error anymore). • Robustness against de-synchronization of slot counter introduced • ►Blind • Phase Network activity is ignored for a configurable period of time following a transmission to minimize effects caused by echoes/ringing ►New synchronization modes (TT-E, TT-L) ►Wake-up during operation Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 14 FlexRay V3.0: Dynamic Segment Robustness (1/2) ►Key • Requirement Improve behavior in case of noise on an undriven link in the dynamic segment (avoid de-synchronization of the slot counter in the cluster) ►Key Characteristics Classification of noise depending on duration of activity • Noise does not lead to a slot counter de-synchronization in case of: • short symmetric noise short asymmetric noise noise after a frame Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 15 FlexRay V3.0: Dynamic Segment Robustness (2/2) FlexRay channel Minislots: noise 11 12 13 14 15 Without noise 5 6 7 8 9 With noise, V2.1 5 6 7 8 With noise, V3.0 5 6 8 9 Slots: ► Activity transmission prohibited shorter than 80 bits is classified as noise. ► Slot counter is increased by two instead of one (i.e., a slot is skipped) to correct the effect of noise on the slot counter. ► Further de-synchronization is avoided by prohibiting transmission in the slot after the detection of noise. ► Efficiency is demonstrated by analytical investigations and statistical experiments. Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 16 FlexRay V3.0: TT-L (1/2) ►TT-L ►Key • (Time-Triggered Local Master Synchronization) Requirement Provide a simple means for cluster startup and synchronization controlled by a single node. ►Key Characteristics Downward compatible to V2.1 • Faster cluster startup • Better cluster precision • Applicable for single or dual channel system • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 17 FlexRay V3.0: TT-L (2/2) FlexRay V2.1 coldstart/ sync node 1 non-sync node ► Coldstart/sync FlexRay V3.0 coldstart/ sync node 2 non-sync node non-sync node TT-L coldstart/ sync node 1 non-sync node non-sync node non-sync node node: Dedicated node for startup of the FlexRay cluster + providing sync frames ► FlexRay V2.1: At least two coldstart nodes are required. ► FlexRay V3.0: Single special coldstart node is allowed (TT-L node). Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 18 FlexRay V3.0: TT-E (1/3) ►TT-E ►Key • (Time-Triggered External Synchronization) Requirement Provide a simple means for connecting FlexRay clusters such that all clusters are synchronized. ►Key Characteristics Alignment of schedules • Synchronization transparent to higher level/host MCU • Applicable to single and dual channel systems • Backward compatible, i.e., can be used to synchronize two FlexRay V2.1 clusters • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 19 FlexRay V3.0: TT-E (2/3) non-sync node non-sync node sync node Time source cluster Time gateway interface Gateway node Source Node FlexRay channel Data Sink Node TT-L node FlexRay channel Time sink cluster non-sync node sync node non-sync node non-sync node non-sync node ► Single gateway node connects both FlexRay clusters ► Gateway node: time gateway source node + time gateway sink node ► Time gateway interface: Clock synchronization ► Time gateway sink node: TT-L node, i.e., single node which drives synchronization in sink cluster Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 20 FlexRay V3.0: TT-E (3/3) Cycle i Static Dynamic Symbol NIT Time source cluster t fixed cycle offset Time sink cluster Static Dynamic Sym NIT Cycle i ► Same cycle length in both clusters ► Fixed cycle offset between clusters ► Clusters can have different schedules (i.e., different numbers of static slots, sizes of static slots, lengths of dynamic segment, lengths of minislots, or lengths of NIT.) Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 21 FlexRay V3.0: Wake-up (1/2) ►Wake-up ►Key • during communication Requirement Wake-up of node(s) during operation/communication ►Key Characteristics Low bandwidth consumption by new wake-up method • Applicable for all bit rates • Every node can initiate wake-up • Downward compatibility: FlexRay V2.1 nodes are not disturbed by the new wake-up method • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 22 FlexRay V3.0: Wake-up (2/2) Wake-up Startup Communication/Operation t Startup frames only Wake-up symbol Static Dynamic Symbol NIT 6 µs WUDOP: Wake-up during operation pattern 6 µs 6 µs 6 µs 6 µs 6 µs ►FlexRay V2.1: Wake-up before startup/communication only ►FlexRay V3.0: Wake-up also during operation possible: WUDOP Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 23 Part 3: Outline ►Part 3: Other network protocols Comparison between FlexRay, CAN, and Ethernet • Extensions of CAN: TTCAN (Time-Triggered Controller Area Network) • Extensions of Ethernet: • TTEthernet PTP (Precision Time Protocol) AVB (Audio Video Bridging) Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 24 Comparison: Overview CAN FlexRay (Fast) Ethernet Access Scheme CSMA/CR TDMA CSMA/CD Carrier sense multiple access/collision resolution Time division multiple access Carrier sense multiple access/collision detection Focus Event triggered, best for small payload Time triggered, deterministic behavior, best for medium payload Event triggered, best for high payload Automotive Application ECU-ECU, ECUSensors Distributed control systems, Backbone Backbone, Programming ECUs, Multimedia Cabling, Topology Twisted pair unshielded, bus Twisted pair unshielded, bus/star With special automotive bus driver: Twisted pair unshielded, star Redundancy No Built in: two separate channels (using 2 x Twisted pair) No (single channel) Deterministic behavior By extension: TTCAN Built in By extensions: TTEthernet, PTP, AVB ECU: Electronic Control Unit, PTP: Precision Time Protocol, TT: Time Triggered Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 25 Comparison: Frame Format ► Frame format: Header: Source, destination, payload length • Trailer: CRC (Cyclic Redundancy Check) • IFG: Intra frame gap • ► Physical Header Max. Payload 22 1500 Ethernet: FlexRay: 5 CAN: 2 254 8 3 Trailer IFG 4 12 3 11 0.4 (CAN: Approx in bytes) layer efficiency: Payload length / (Frame length + IFG) • Considers coding scheme. FlexRay: NRZ, (Fast) Ethernet: 4B5B • ► Hamming distance: Ability to detect corrupted data • Ethernet: Some ability to detect corrupted data, but FlexRay and CAN are better. • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 26 Comparison: Net Data Rate ► Net • data rate: Based on physical bit rate: • @125 MHz CAN: 1 MHz FlexRay: 10 MHz Fast Ethernet: 125 MHz @10 MHz @1 MHz Considers: Header/trailer Intra frame gap Collisions (in Ethernet) ► Collisions in Ethernet: Due to access scheme (CSMA/CD) • Experiments: ~20% losses in net data rate due to collisions [Boggs et. al., 1988] • Collisions can be reduced/avoided in switched Ethernets. Bus: Node 1 Node 2 Node 3 Node 4 • Collision Switch: Node 1 Switch Node 3 Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. Node 2 Node 4 TM 27 CAN Extension: TTCAN 1bit recessive 11bits 3bits 4bits 0...64bits ... dominant Start of frame Message ID Various flags Length Data t ► CAN: Standardized as ISO 11898 • CSMA/CR: Carrier Sense Multiple Access/Collision Resolution • Collision resolution: Bit-wise arbitration in Message ID: “0” dominates over “1” Æ higher IDs dominate over lower IDs • Latency of messages not deterministic if low ID and more than one sender • ► TTCAN: Standardized in Part 4 of ISO 11898 • Time triggered extension for CAN: Determinism for CAN • Special TTCAN nodes transmit sync frames Æ Schedule • Can be implemented in software • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 28 Ethernet Extension: TTEthernet TTEthernet Node Node TT Ethernet Switch TTEthernet Node Node ► Ethernet: Standardized in IEEE 802.3 • CSMA/CD: Carrier Senses Multiple Access/Collision Detection • Collision detection: Before sending: check for activity. If Activity: Retry after certain amount of time • Latency of messages not deterministic if more than one sender • ► TTEthernet: Time triggered extension for Ethernet: Determinism for Ethernet • Special TTEthernet nodes transmit sync frames Æ Schedule • TTEthernet switch required to guarantee transmission of sync frames • TTEthernet in nodes can be implemented in software • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 29 Ethernet Extension: PTP ► PTP: Precision Time Protocol (IEEE 1588) ► Time synchronization in a network ► Time stamping (TS) in nodes required ► Alternatives for time stamping: In software by microcontroller Æ lowest precision (~20µs) • In hardware by extended Ethernet module (MAC) • In hardware by extended physical bus driver (PHY) Æ best precision (~40ns) Node 1: Master Clock Node 2: Slave Clock Now, it's 9:05 ! OK, 9:05 ! PTP jitter • TS TS PTP UDP UDP IP IP MAC MAC PHY PHY jitter Network Ethernet PTP Packet Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 30 Ethernet Extension: AVB ► AVB: • • • • • Audio Video Bridging Extension to IEEE 802.1 (Network bridging) Target: 2 ms guaranteed latency through 7 Ethernet bridges/switches Time synchronization by PTP: IEEE 802.1AS Quality of service, stream reservation: IEEE 802.1Qat Forwarding and queuing: IEEE 802.1Qav Display Multimedia Server Ethernet Switch AVB AVB Speaker AVB AVB Display AVB Speaker Ethernet Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. AVB TM 31 Session Summary ►FlexRay: Built-in time triggered: deterministic communication • V3.0: downward compatible + interesting new features • Best for medium data rates (~10 Mbit/s) • ►CAN: Event triggered, not deterministic • Best for low data rates (~1 Mbit/s) • Extensions available • ►Ethernet: Event triggered, not deterministic • Best for high data rates (>10 Mbit/s) • Extensions available • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 32 For Further Information ►FlexRay: www.Freescale.com/Flexray • www.flexray.com • Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, C-Ware, mobileGT, PowerQUICC, StarCore, and Symphony are trademarks of Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. BeeKit, BeeStack, CoreNet, the Energy Efficient Solutions logo, Flexis, MXC, Platform in a Package, Processor Expert, QorIQ, QUICC Engine, SMARTMOS, TurboLink and VortiQa are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © 2010 Freescale Semiconductor, Inc. TM 33 TM