IEC 61158-6-4:2023

IEC 61158-6-4 ®
Edition 4.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-4: Application layer protocol specification – Type 4 elements

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IEC 61158-6-4 ®
Edition 4.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –

Part 6-4: Application layer protocol specification – Type 4 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-6632-8

– 2 – IEC 61158-6-4:2023 © IEC 2023
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
1.1 General . 8
1.2 Specifications . 8
1.3 Conformance . 9
2 Normative references . 9
3 Terms, definitions, symbols, abbreviated terms and conventions . 10
3.1 Referenced terms and definitions . 10
3.1.1 ISO/IEC 7498-1 terms . 10
3.1.2 ISO/IEC 8822 terms . 10
3.1.3 ISO/IEC 9545 terms . 10
3.1.4 ISO/IEC 8824-1 terms . 10
3.1.5 Fieldbus data-link layer terms . 11
3.2 Abbreviations and symbols . 11
3.3 Conventions . 12
3.3.1 General concept . 12
3.3.2 Conventions for state machines for Type 4 . 12
4 FAL syntax description . 13
4.1 FAL-AR PDU abstract syntax . 13
4.1.1 General . 13
4.1.2 Abstract syntax of APDU header . 13
4.1.3 Abstract syntax of APDU body . 15
4.2 Data types . 16
5 Transfer syntaxes . 16
5.1 APDU encoding . 16
5.1.1 APDU Header encoding . 16
5.1.2 APDU body encoding . 18
5.2 Variable object encoding and packing . 20
5.2.1 Encoding of simple variables . 20
5.2.2 Encoding of constructed variables . 21
5.2.3 Alignment . 22
5.2.4 Variable object attributes . 24
5.3 Error codes . 25
6 FAL protocol state machines . 26
7 AP-context state machine . 27
8 FAL service protocol machine (FSPM) . 27
8.1 Primitives exchanged between FAL User and FSPM . 27
8.2 FSPM states . 27
8.2.1 General . 27
8.2.2 FSPM proxy object states . 27
8.2.3 FSPM real object state machine description . 32
9 Application relationship protocol machine (ARPM) . 34
9.1 Primitives exchanged between ARPM and FSPM . 34
9.2 ARPM States . 35
9.2.1 General . 35

9.2.2 Sender state transitions . 35
9.2.3 Receiver state transitions . 36
10 DLL mapping protocol machine (DMPM) . 37
10.1 Data-link Layer service selection. 37
10.1.1 General . 37
10.1.2 DL-UNITDATA request . 37
10.1.3 DL-UNITDATA indication . 37
10.1.4 DL-UNITDATA response . 37
10.1.5 DLM-Set primitive and parameters . 37
10.1.6 DLM-Get primitive and parameters . 37
10.2 Primitives exchanged between ARPM and DLPM . 37
10.3 Primitives exchanged between DLPM and data-link layer . 38
10.4 DLPM states . 38
10.4.1 States . 38
10.4.2 Sender state transitions . 38
10.4.3 Receiver state transitions . 39
11 Protocol options. 40
Bibliography . 41

Figure 1 – State transition diagram . 12
Figure 2 – APDU header structure . 16
Figure 3 – Subfields of ControlStatus for Request . 17
Figure 4 – Subfields of ControlStatus for Response with error . 17
Figure 5 – Subfields of ControlStatus for Response with no error . 18
Figure 6 – DataFieldFormat encoding . 18
Figure 7 – Structure of request APDU body . 19
Figure 8 – Structure of response APDU body . 19
Figure 9 – Variable identifier . 19
Figure 10 – Code subfield of variable identifier . 19
Figure 11 – Sequence of data in the APDU body subfield . 21
Figure 12 – MSG consists of APDU header and APDU body . 22
Figure 13 – Summary of FAL architecture . 26
Figure 14 – FSPM proxy object state machine . 28
Figure 15 – FSPM real object state machine . 33
Figure 16 – ARPM state machine . 35
Figure 17 – DLPM state machine . 38

Table 1 – State machine description elements . 12
Table 2 – APDU header . 13
Table 3 – APDU body . 15
Table 4 – Transfer syntax for Array . 23
Table 5 – Transfer syntax for Structure . 23
Table 6 – Common variable object attributes . 24
Table 7 – Variable type identifiers . 24
Table 8 – FIFO variable object attributes . 25

– 4 – IEC 61158-6-4:2023 © IEC 2023
Table 9 – Error codes . 25
Table 10 – Primitives exchanged between FAL-User and FSPM . 27
Table 11 – REQUEST.req FSPM constraints . 28
Table 12 – REQUEST.req FSPM actions . 29
Table 13 – RESPONSE.cnf FSPM constraints . 31
Table 14 – RESPONSE.cnf FSPM actions .
...