61158-4-8-2007 Réseaux de communication industriels – Spécifications de bus de terrain – Partie 4-8: Spécification du protocole de couche liaison de données – ?léments de Type 8 (Edition 1.0)
Industrial communication networks – Fieldbus specifications – Part 4-8: Data-link layer protocol specification – Type 8 elements (Edition 1.0)
Réseaux de communication industriels – Spécifications de bus de terrain – Partie 4-8: Spécification du protocole de couche liaison de données – ?léments de Type 8 (Edition 1.0) 是非强制性国家标准，您可以免费下载前三页
General The data-link layer provides basic time-critical messaging communications between devices in an automation environment. This protocol provides a highly-optimized means of interchanging fixed-length input/output data and variable-length segmented messages between a single master device and a set of slave devices interconnected in a loop (ring) topology. The exchange of input/output data is totally synchronous by configuration@ and is unaffected by the messaging traffic. Devices are addressed implicitly by their position on the loop. The determination of the number@ identity and characteristics of each device can be configured@ or can be detected automatically at start-up.