Communication Protocol Stacks


Communication is the most important component in Automotive ECUs. The Automotive communication standards are standardizing the inter communication between different types of ECUs, sensors and actuators in a vehicle.

There are specific protocol standards for type of vehicle E.g. CAN communication standards.

The vehicle tracking systems sends important vehicle information and alerts to cloud, this information can be used for fleet management, asset tracking, driver behavior monitoring and vehicle usage monitoring. The OEMs can use the information for warranty checks.

Following are the key features of Vehicle tracking system


  • ISO 15765 ‒ CAN Communication standard for ECUs in cars
  • J1939 ‒ CAN Communication standard for ECUs in heavy duty vehicles
  • J1939 ‒ CAN Communication standard for ECUs in heavy duty vehicles
Communication Stacks

J1939 ‒ CAN Communication standard for ECUs in heavy duty vehicles

Accord CAN protocol stacks developed to AUTOSAR COMSTACK standard (ver 4.4 ).

Signal layer: Signal layer provides abstraction to entire CAN stack. Application components can read and write CAN signals without knowing full details about underling CAN protocol.

COM: COM receives CAN signals from PDU Router and provides it to Signal layer, and it reads CAN transmit signal from Signal layer and sends to PDU Router.

DCM: Diagnostic Communication Manager receives diagnostic service requests (e.g. Program Loading, Uploading, Read Diagnostic data, Clear Diagnostic data, Start and Stop communication transmission, Reset processor, Read/write data by identifier and address etc.. ) from Tester via PDU Router and performs diagnostics and sends response accordingly.

Protocol

PDU Router: PDU Router receives data from CAN Interface (single frame) and CAN Transport layer (multi frame) and routes the data to either COM or DCM according to the configured routing table. Similarly, it receives data from COM and DCM and sends to CAN Interface or CAN Transport layer.

CAN SM: CAN state manager allows communication to be in one of the three communication modes (NO COMMUNICAITON i.e. No Tx and Rx, SILENT COMMUNICTION i.e. Only Rx and FULL COMMUNICATION i.e. both Tx and Rx), it gets request from Communication manager to enter into one of the communication state, and it sends request to CAN IF for controlling CAN Controller accordingly.

CAN NM: The CAN Network manager coordinates network sleep/shutdown operation with other nodes in the same network.

Communication Protocol


Accord AUTOSAR COMSTACK supports the following CAN protocol stacks


  •   CAN communication protocol (ISO 15765)
  •   UDS - CAN based diagnostic protocol stack (ISO 14229)
  •   UDS based boot loader software

Other CAN protocol stacks


  •   CanOpen

The main advantage with our protocol stacks


  •   Configurable CAN matrix
  •   Small memory footprint
  •   Optimized for less stack usage
  •   Optimized for less CPU cycles usage
  •   Easy to integrate with application
  •   Pre verified
  •   Easily portable to new hardware
  •   Remote and on-site support in integration

Accord provides the following services in communication stacks


  •   CAN drivers
  •   ISO 15765, ISO 14229(UDS) and CanOpen stacks
  •   Design and develop proprietary communication protocols according to customer requirements
  •   Integrate communication stacks into Application
  •   Design and development of UDS based boot loader software.
Functional Safety