Future applications in the automotive domain such as distributed control functions need a highly dependable communication system. The current FlexRay standard already provides high transmission speeds and addresses deterministic data communication.
This paper shows how to enhance the safety properties for handling a new set of applications and speeding up the communication even more. The concept of Layered FlexRay is based on the FlexRay protocol and addresses the requirements of safety-relevant applications in a distributed communication network.
An implementation of this approach is depicted with a Safety Core hardware chip. It is designed to handle the communication between the FlexRay system beneath and the application on the host CPU above, providing highly efficient data management and execution of safety functions which otherwise would have to be executed in software on the host CPU. A set of new safety features and diagnosis functions is introduced into the communication system.
These extended services, a set of proven mechanisms [1], are combined with FlexRay to provide safety, flexibility, and cost effectiveness for the automotive industry standard.
In the future, this approach may go even further by combining classic FlexRay and the extended services to a single chip. This allows the development of a standardized time-triggered architecture for safety-relevant and fault-tolerant applications; such an architecture connects all control units in a car and leads to new domains of applications that have the possibility to interact with all control functions of a car to make driving more comfortable and safer.