BS EN 61158-4-4:2014
$189.07
Industrial communication networks. Fieldbus specifications – Data-link layer protocol specification. Type 4 elements
| Published By | Publication Date | Number of Pages |
| BSI | 2014 | 50 |
1.1 General
The data-link layer provides basic time-critical messaging communications between devices in an automation environment.
This protocol provides a means of connecting devices through a partial mesh network, such that most failures of an interconnection between two devices can be circumvented. In common practice the devices are interconnected in a non-redundant hierarchical manner reflecting application needs
1.2 Specifications
This standard specifies
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procedures for the timely transfer of data and control information from one data-link user entity to a peer user entity, and among the data-link entities forming the distributed data-link service provider;
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the structure of the fieldbus DLPDUs used for the transfer of data and control information by the protocol of this standard, and their representation as physical interface data units.
1.3 Procedures
The procedures are defined in terms of
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the interactions between peer DL-entities (DLEs) through the exchange of fieldbus DLPDUs;
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the interactions between a DL-service (DLS) provider and a DLS-user in the same system through the exchange of DLS primitives;
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the interactions between a DLS-provider and a Ph-service provider in the same system through the exchange of Ph-service primitives.
1.4 Applicability
These procedures are applicable to instances of communication between systems which support time-critical communications services within the data-link layer of the OSI or fieldbus reference models, and which require the ability to interconnect in an open systems interconnection environment.
Profiles provide a simple multi-attribute means of summarizing an implementation’s capabilities, and thus its applicability to various time-critical communications needs.
1.5 Conformance
This standard also specifies conformance requirements for systems implementing these procedures. This standard does not contain tests to demonstrate compliance with such requirements.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 6 | English CONTENTS |
| 8 | INTRODUCTION |
| 9 | 1 Scope 1.1 General 1.2 Specifications 1.3 Procedures 1.4 Applicability 1.5 Conformance |
| 10 | 2 Normative references 3 Terms, definitions, symbols and abbreviations 3.1 Reference model terms and definitions |
| 12 | 3.2 Service convention terms and definitions |
| 13 | 3.3 Terms and definitions |
| 16 | 3.4 Symbols and abbreviations 4 Data Link Protocol Definition 4.1 Overview of the DLprotocol |
| 17 | Figures Figure 1 – Relationship of PhE, DLE and DLS-user |
| 19 | Figure 2 – DLE state diagram for confirmed and unconfirmed, unacknowledged DLPDUs |
| 20 | Figure 3 – DLE state diagram for confirmed acknowledged DLPDUs |
| 21 | Figure 4 – DLE state diagram for unconfirmed acknowledged DLPDUs |
| 22 | Figure 5 – Full duplex DLE receive state diagram Figure 6 – Full duplex DLE transmit state diagram |
| 25 | Figure 7 – Link access example |
| 28 | 4.2 General structure and encoding of PhIDUs and DLPDUs, and related elements of procedure |
| 31 | Figure 8 – Simple Type 4-route format Figure 9 – Extended Type 4-route format |
| 32 | Figure 10 – Complex Type 4-route format Figure 11 – Immediate Type 4-route format |
| 33 | Figure 12 – IP Type 4-route format |
| 34 | Figure 13 – Control-status format Figure 14 – Data-field-format |
| 35 | 4.3 DLPDU-specific structure, encoding and elements of procedure Tables Table 1 – Summary structure of DLPDUs |
| 36 | Table 2 – Structure of confirmed DLPDUs |
| 37 | Table 3 – Structure of unconfirmed DLPDUs |
| 38 | Table 4 – Structure of acknowledge DLPDU Table 5 – Structure of immediate-reply DLPDU |
| 39 | 4.4 DLservice elements of procedure |
| 42 | 4.5 Route mechanism |
| 43 | Figure 15 – Source / destination designator Figure 16 – Simple Type 4-route generation Figure 17 – Extended Type 4-route generation |
| 44 | Figure 18 – Complex and IP Type 4-route generation Figure 19 – Simple DLroute generation |
| 45 | 4.6 Link-access system Figure 20 – Extended DLroute generation Figure 21 – Complex and IP DLroute generation |
| 46 | 4.7 Local variables, counters and queues |
| 48 | Bibliography |
