Real-time FlexRay, CAN/CAN-FD and LIN

Automotive technologies have made giant leaps in the past few years. Software especially, has become an increasingly integral part for vehicle safety, comfort and driving assistance. This is accompanied by the rising advances in computer technology and standardized bus systems for the networking of individual vehicle systems. Three of the most important bus systems are FlexRay, CAN/CAN-FD and LIN.

Kithara RealTime Suite is a modular real-time extension that provides several mechanisms to optimally perform tasks in real-time automotive networking. These are the core features:


FlexRay

The automotive field bus FlexRay is mainly used for sophisticated functions in modern automobiles. Due to its high transfer rate of 10 Mbit/s, FlexRay can be applied optimally for high-end features such as driver assistant and chassis control systems. Using dual-channel wiring the data rate can either be doubled or the second communication channel can provide redundant data transfer, which makes it possible for FlexRay to be implemented for safety-critical functions.

Real-Time capabilities for FlexRay enable automotive and test system manufacturers to efficiently test the above-mentioned car functions. For example, by employing guaranteed fast reaction times highly precise measurement data can be generated, thus achieving extremely accurate test results.


FlexRay Module

FlexRay communication in real-time

  • Common
  • Features
  • Hardware-support

As part of the Kithara real-time extension, the FlexRay Module represents an essential link between test software and physical test system, which allows for the application of real-time capabilities with accurate cycles for high-precision operations.

With the FlexRay Module, a Windows PC can be utilized as an actual FlexRay node. This includes the assignment as leading or following node, as active or passive point of communication within the network. Both FlexRay channels can be configured independently from each other while it is possible to flexibly adjust their baud rate (2,5/5/10 Mbit/s).

  • Real-time FlexRay communication
  • Independent configuration of FlexRay channels
  • Windows PC used as FlexRay node
  • Assignment as leading or following node
  • Baud rate flexibly adjustible (2,5/5/10 Mbit/s)

The following FlexRay cards are supported:

  • FlexCard PMC II (Star Cooperation)

These specifications always refer to the latest version of our software.


CAN (Controller Area Network) and CAN-FD

CAN (Controller Area Network) is a serial bus system, which was originally developed for control systems in the automobile industry. However, it is qualified for networking of intelligent electronic devices as well as sensors and actuators in a machine or factory. CAN is a serial multi-master bus system, that implies that multiple CAN nodes can request an access simultaneously, but the order of the actual singular access of a node is determined during the access procedure. The ISO 11898 standardized bus system has real-time capability and uses two layers of the ISO/OSI reference model.

  • Low integration cost
  • Reliable even under strainful conditions
  • Very good real-time capabilitiest and easy usability

CAN communication in real time for Windows

CAN communication mostly requires a stable, time equidistant data exchange as well as a fast reaction to external events. However, most of the CAN boards cannot fulfil these requirements, because the basic Windows drivers, which are included in the delivery can only be used from an application context and therefore, are not real-time capable. The CAN Module closes this gap and enables CAN communication in real-time.

The CAN Module from Kithara RealTime Suite provides solutions for automated process that require real-time connections. The function library is especially suitable for developers and engineers that require time-critical processing of CAN messages.

IXXAT PCI

At transmission and receiving, the CAN messages are buffered through a simple and intuitive Application Programming Interface (API). It is possible to implement customized real-time message filters as well as error handling routines for predetermined bus events. A Listen-Only Mode is also possible. For straightforward monitoring, Kithara Kernel Tracer is can be used to trace the entire CAN data traffic within a microsecond resolution

For maximum flexibility regarding CAN hardware, a real-time driver for common CAN boards of different manufacturers is provided, enabling manufacturer-independent programming.

CAN-FD

CAN-FD (Flexible Data Rate) is an extension of the CAN protocol that expands the payload capacity from 8 bytes to 64 bytes, thus achieving increased data rates of up to 8 times higher than classic CAN, without raising integration costs. The protocol also benefits from advanced data safety due to improvements to the cyclic redundancy check.

This is why CAN-FD will have a set place in the future automotive development. For this the bus system requires a coherent high-performance real-time solution, which combines all interfaces involved in order to even allow for the implementation of many development and test processes.

CAN Module

CAN communication in real-time

  • Common
  • Features
  • Hardware-support

The CAN Module allows for real-time for the fieldbus CAN (CAN 2.0B compatible) and CAN-FD. The API is manufacturer-independent, thus an initial training has to be done once in order to program CAN(FD) hardware.

The immediately reaction to receiving massages enables that CallBack functions can react immediately to failure situations. Even with high baud rates and bus loads messages do not get lost, because the transmit and reception buffer is big enough. Additionally, it is possible to create filter routines, which can be executed directly by receiving messages.

At analytical tasks the CAN(FD) interface has to be complete passive; a listen only mode is supported. Furthermore, by using a SJA1000 CAN controller the “Error Code Capture” register can be read, with the result that further information for failure analysis is provided.

  • CAN data exchange in real-time
  • Support for CAN FD (Flexible Data Rates)
  • Instantaneous transmission and immediate reaction
  • Transmission and reception at kernel level possible
  • Customized filter routines through CallBack functions possible
  • Reception of messages either through Callback interrupt context, at kernel level, or polling process
  • Transmit and receive routines directly form real-time context callable
  • Utilization of the kernel level supports C/C++ or Delphi (Win32 native)

At the moment the CAN Module supports PCI based cards with 1, 2, or 4 channels of Peak, Star Cooperation (Eberspächer), EMS Dr. Wünsche, ESD, Ixxat and Kvaser (see the listing below). We would gladly implement support for your preferred card. The following list always refers to the latest version of our software:

 

Peak System

Star Cooperation (Eberspächer)

  • FlexCard PMC-II
    • FlexTiny II CAN-HS (D_CAN), dual to octo-channel, optional opto-uncoupled
    • FlexTiny II CAN-FD (M_TTCAN), dual to octo-channel, optional opto-uncoupled

EMS Dr. Thomas Wünsche

  • CPC-PCI, CPC-PCIe (single-, dual-, four-channel) and CPC-104P with SJA1000

ESD—Electronic System Design CAN-PCI

  • CAN-PCI /200/266, opto-uncoupled, single and dual-channel
  • CAN-PCIe /200, opto-uncoupled, single and dual-channel
  • CAN-PCI-104 /200, opto-uncoupled, single and dual-channel
  • CPCI-CAN /200, opto-uncoupled, single and dual-channel
  • PMC-CAN /266, opto-uncoupled, single and dual-channel

Ixxat

Kvaser Advanced CAN Solutions

The correct functioning of the software in conjunction with specific components cannot be entirely guaranteed due to the large number of potential hardware variations. For questions regarding the com­pa­ti­bil­ity with individual hardware configurations, please contact us.

LIN (Local Interconnect Network)

LIN is commonly used to apply cost-efficient automotive applications since its single wire networking allows for significant cost and weight reductions.

As a popular serial network protocol commonly used in automotive engineering, LIN is deployed for increasingly complex automotive applications to be integrated cost-efficiently.

Due to the fact that LIN is primarily used in cars subsystems, it needs to be linked to a higher-level backbone network, which is why the LIN master node often represents the gateway to a real-time CAN bus system as well.

LIN Module

LIN communication in real-time

  • Common
  • Features
  • Hardware-support

By using the LIN Module of Kithara RealTime Suite it is possible to attain real-time with LIN. A master or slave node can be created easily using a common PC with a UART interface. Unlike the case of using a microcontroller, this allows for easier logging of existing LIN networks as well as more efficient debugging procedures. Sending nodes will automatically recheck their transmitted data on a bus, which enables the detection of collisions.

  • LIN data exchange in real-time
  • Easy implementation of a master or slave node using a common PC
  • Only a low cost LIN transceiver required (e. g. Freitag RS232-LIN)
  • Bus collisions detection
  • Automatic checksum validation (LIN version 1.x and 2.x)
  • Data rates up to 20 kbit/s
  • Guaranteed latency times
  • Receive LIN messages either using callbacks or polling
  • UART (the use of common RS232 interfaces requires a level converter, e. g. Freitag RS232-LIN
  • Peak PCAN-USB Pro (in development)
  • more on request

    These specifications always refers to the latest version of our software.

BroadR-Reach

BroadR-Reach is a pyhsical Ethernet transport layer specially for automotive networking. The benefits of Ethernet in automotive networking are extremely fast transmission rates, high scalability as well as cost efficiency regarding wiring and programming. This way, for instance, real-time Ethernet can be used as a central backbone network.

The implementation of BroadR-Reach closes the gap between the Kithara real-time Ethernet drivers and moderen automotive wiring. With guaranteed reaction times thanks to the Kithara real-time system, data can be accurately captured and embedded into sopisticated test processes via the Ethernet transport layer. This enables automotive developers to directly access and test physical Ethernet networks in vehicles.

Due to the fact that BroadR-Reach defines a physical Ethernet transport layer, it exists as an extension of the Network Module within the RealTime Suite.