IEC 61158-6-2:2014 defines the protocol provided to define the wire-representation of the service primitives defined in IEC 61158-5-2, and define the externally visible behavior associated with their transfer. This standard specifies the protocol of the Type 2 fieldbus application layer, in conformance with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). This third edition cancels and replaces the second edition published in 2010 and constitutes a technical revision. The main changes are:
- Updates of definition used by the Time Sync object;
- Addition of "member" and object specific services in 4.1.2.1, 4.1.8, 4.1.10, 8.2;
- Removal of obsolete transport classes 4 to 6 in 4.1.4.6, and 9.3.9 to 9.3.12;
- Clarification of transport header formats in 4.1.4;
- Update of CM and MR PDUs in 4.1.5 to 4.1.7;
- Updates of Identity object PDUs in 4.1.8.2;
- Updates of Assembly object PDUs in 4.1.8.4;
- Updates of Time sync object PDUs in 4.1.8.6;
- Updates of Parameter object PDUs in 4.1.8.7;
- Updates of Connection Manager object PDUs in 4.1.8.8;
- Updates of message and connection paths in 4.1.9;
- Updates of object class codes in 4.1.10 and error codes in 4.1.11;
- Updates of data types in 4.2.4 and 5.2.3;
- Updates of the encapsulation abstract syntax in 4.3;
- Updates to the DLL mapping protocol machine 2 in Clause 11.