PREEvision – LDF, DBC, FIBEX, and ARXML Ethernet Communication

Functions / Features

Signal Mapping

The communication of data elements over a bus is represented in AUTOSAR by the system signal. In order to trace the alignment of these two elements, it is necessary to define a mapping link from the data element (software layer) to a system signal (communication layer). This is called data mapping in AUTOSAR.

Signal Router

In the main network diagram, the signal paths defined by the signal router can be highlighted.

Another important aspect in this phase of the system description is the definition of routes of individual system signals. The signal router supports the completion of the communication matrix.

It calculates the best route for the signals with the data elements to be transferred. Many communication artifacts are generated automatically by the signal router. In addition to many routing options and routing via delta states, all routed signals can also be displayed graphically in networking diagrams.

CAN (FD), LIN, and FlexRay

PDU layout and frame layout for CAN and CAN FD communication.

In order to transmit system signals over the bus, additional details must be defined. Each bus segment is configured dependent on its technology here. One component of this configuration is the PDU layout and frame layout. In this phase, signals are arranged in PDUs, which are in turn assigned to frames.

Other communication attributes are also specified, such as the data type, send mode, initial value, scheduling, network management, transport protocol etc. A special editor is available for creating and editing frames, PDUs and signals. Protocol-specific editors for CAN, CAN FD, LIN, FlexRay, and Ethernet are also available. For integration with additional tools, PREEvision supports the LDF, DBC and FIBEX formats in addition to AUTOSAR.

Partial Networking

With partial networking, parts of architectures can switch off temporarily to conserve available resources. For this purpose, clusters that can switch off and on and be monitored via control and status ports are defined in PREEvision.

Ethernet

Ethernet is being adopted as a bus technology in vehicles. PREEvision supports AUTOSAR compliant service and communication design for Ethernet communication in vehicles. The signal router can define VLANs and also calculate the communication path for defined VLANs.

J1939

PREEvision also supports CAN network protocol SAE J1939 for commercial vehicles, including ISO 11783 (ISOBUS) for agricultural machines.

ISOBUS enables uniform and easy control of different add-on equipment from the cab of the tractor. The expanded CAN multiplexing required here is supported.

Secured Communication 

Due to safety-critical functions like autonomous driving, security for onboard communication is growing more and more important. PREEvision supports solutions like Secured Onboard Communication (SecOC) und Transport Layer Security (TLS). This allows the direct implementation of the safety goals in the model.