A time-predictable open-source TTEthernet end-system

Cyber-physical systems deployed in areas like automotive, avionics, or industrial control are often distributed systems. The operation of such systems requires coordinated execution of the individual tasks with bounded communication network latency to guarantee quality-of-control. Both the time for computing and communication needs to be bounded and statically analyzable. To provide deterministic communication between end-systems, real-time networks can use a variety of industrial Ethernet standards typically based on time-division scheduling and enforced by real-time enabled network switches. For the computation, end-systems need time-predictable processors where the worst-case execution time of the application tasks can be analyzed statically. This paper presents a time-predictable end-system with support for deterministic communication using the open-source processor Patmos. The proposed architecture is deployed in a TTEthernet network, and the protocol software stack is implemented, and the worst-case execution time is statically analyzed. The developed end-system is evaluated in an experimental network setup composed of six TTEthernet nodes that exchange periodic frames over a TTEthernet switch.