A Time-predictable TTEthenet Node

Distributed real-time systems need time-predictable computation and communication to facilitate static analysis of timing requirements and deadlines. This paper presents the implementation of a deterministic network protocol, TTEthernet, on the time-predictable Patmos processor. The implementation uses the existing Ethernet controller on the processor and we tested it with a TTEthernet system provided by TTTech Inc. Further testing showed that the controller could send time-triggered messages with bounded latency and a small jitter of approximately 4.5 us. We also provide worst-case execution time analysis of the network code, which demonstrates a time-predictable end-to-end solution. This work enables Patmos to communicate with other nodes in a deterministic way. Thus, extending the possible uses of Patmos.