標準號：DIN EN 61158-4-8-2008
中文標準名稱：工業(yè)通訊網(wǎng)絡(luò).現(xiàn)場總線規(guī)范.第4-8部分:數(shù)據(jù)聯(lián)絡(luò)層協(xié)議規(guī)范.8型元件.僅為CD-ROM
英文標準名稱：Industrial communication networks - Fieldbus specifications - Part 4-8: Data-link layer protocol specification - Type 8 elements (IEC 61158-4-8:2007); English version EN 61158-4-8:2008, only on CD-ROM
標準類型：N18;P76
發(fā)布日期：1999/12/31 12:00:00
實施日期：2008/9/1 12:00:00
中國標準分類號：N18;P76
國際標準分類號：35.100.20;35.160;35.240.50
引用標準：IEC 61158-2;IEC 61158-3-8;ISO/IEC 7498-1;ISO/IEC 7498-3;ISO/IEC 10731
適用范圍：1.1 GeneralThe data-link layer provides basic time-critical messaging communications between devices in anautomation environment.This protocol provides a highly-optimized means of interchanging fixed-length input/output data andvariable-length segmented messages between a single master device and a set of slave devicesinterconnected in a loop (ring) topology. The exchange of input/output data is totally synchronousby 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 atstart-up.1.2 SpecificationsThis standard specifiesa) procedures for the timely transfer of data and control information from one data-link user entityto a peer user entity, and among the data-link entities forming the distributed data-link serviceprovider;b) the structure of the fieldbus DLPDUs used for the transfer of data and control information by theprotocol of this standard, and their representation as physical interface data units.1.3 ProceduresThe procedures are defined in terms ofa) the interactions between peer DL-entities (DLEs) through the exchange of fieldbus DLPDUs;b) the interactions between a DL-service (DLS) provider and a DLS-user in the same systemthrough the exchange of DLS primitives;c) the interactions between a DLS-provider and a Ph-service provider in the same system throughthe exchange of Ph-service primitives.1.4 ApplicabilityThese procedures are applicable to instances of communication between systems which supporttime-critical communications services within the data-link layer of the OSI or fieldbus referencemodels, and which require the ability to interconnect in an open systems interconnectionenvironment.Profiles provide a simple multi-attribute means of summarizing an implementation’s capabilities, andthus its applicability to various time-critical communications needs.1.5 ConformanceThis standard also specifies conformance requirements for systems implementing theseprocedures. This standard does not contain tests to demonstrate compliance with suchrequirements.