IEC 61158-6-2:2010

IEC 61158-6-2 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –
Part 6-2: Application layer protocol specification – Type 2 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 6-2: Spécification de protocole de la couche application – Eléments de
Type 2
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IEC 61158-6-2 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 6-2: Application layer protocol specification – Type 2 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 6-2: Spécification de protocole de la couche application – Eléments de

Type 2
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XH
CODE PRIX
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-83220-125-1

– 2 – 61158-6-2  IEC:2010
CONTENTS
FOREWORD . 12
INTRODUCTION . 14
1 Scope . 15
1.1 General . 15
1.2 Specifications . 15
1.3 Conformance . 16
2 Normative references . 16
3 Terms, definitions, symbols, abbreviations and conventions . 17
3.1 Terms and definitions from other ISO/IEC standards . 17
3.2 Terms and definitions from IEC 61158-5-2. 18
3.3 Additional terms and definitions . 18
3.4 Abbreviations and symbols . 24
3.5 Conventions . 24
3.6 Conventions used in state machines . 29
4 Abstract syntax . 30
4.1 FAL PDU abstract syntax . 30
4.2 Data abstract syntax specification . 120
4.3 Encapsulation abstract syntax . 124
5 Transfer syntax . 138
5.1 Compact encoding . 138
5.2 Data type reporting . 145
6 Structure of FAL protocol state machines . 150
7 AP-Context state machine . 150
7.1 Overview . 150
7.2 Connection object state machine . 150
8 FAL service protocol machine (FSPM) . 160
8.1 General . 160
8.2 Primitive definitions . 160
8.3 Parameters of primitives . 164
8.4 FSPM state machines . 165
9 Application relationship protocol machines (ARPMs) . 166
9.1 General . 166
9.2 Connection-less ARPM (UCMM) . 166
9.3 Connection-oriented ARPMs (transports) . 176
10 DLL mapping protocol machine 1 (DMPM 1) . 247
10.1 General . 247
10.2 Link producer . 247
10.3 Link consumer . 248
10.4 Primitive definitions . 248
10.5 DMPM state machine . 250
10.6 Data-link Layer service selection . 251
11 DLL mapping protocol machine 2 (DMPM 2) . 251
11.1 General . 251
11.2 Mapping of UCMM PDUs . 252
11.3 Mapping of transport class 0 and class 1 PDUs . 257

61158-6-2  IEC:2010 – 3 –
11.4 Mapping of transport class 2 and class 3 PDU’s . 258
11.5 Mapping of transport classes 4 to 6 . 258
11.6 IGMP Usage . 258
11.7 Quality of Service (QoS) for CP 2/2 messages . 259
11.8 Management of an encapsulation session . 262
12 DLL mapping protocol machine 3 (DMPM 3) . 263
Bibliography . 264

Figure 1 – Attribute table format and terms . 25
Figure 2 – Service request/response parameter . 25
Figure 3 – Example of an STD . 29
Figure 4 – Network connection parameters . 49
Figure 5 – Time tick . 51
Figure 6 – Connection establishment time-out . 53
Figure 7 – Transport Class Trigger attribute . 86
Figure 8 – CP2/3_initial_comm_characteristics attribute format . 89
Figure 9 – Segment type . 97
Figure 10 – Port segment . 98
Figure 11 – Logical segment encoding . 100
Figure 12 – Extended network segment . 104
Figure 13 – Encapsulation message . 124
Figure 14 – FixedLengthBitString compact encoding bit placement rules . 142
Figure 15 – Example compact encoding of a SWORD FixedLengthBitString . 142
Figure 16 – Example compact encoding of a WORD FixedLengthBitString . 142
Figure 17 – Example compact encoding of a DWORD FixedLengthBitString . 143
Figure 18 – Example compact encoding of a LWORD FixedLengthBitString . 143
Figure 19 – Example 2 of formal encoding of a structure type specification . 147
Figure 20 – Example of abbreviated encoding of a structure type specification . 148
Figure 21 – Example 1 of formal encoding of an array type specification . 148
Figure 22 – Example 2 of formal encoding of an array type specification . 149
Figure 23 – Example 1 of abbreviated encoding of an array type specification . 149
Figure 24 – Example 2 of abbreviated encoding of an array type specification . 150
Figure 25 – I/O Connection object state transition diagram . 151
Figure 26 –Bridged Connection object state transition diagram . 155
Figure 27 – Explicit Messaging Connection object state transition diagram . 157
Figure 28 – State transition diagram of UCMM client . 169
Figure 29 – State transition diagram of high–end UCMM server . 170
Figure 30 – State transition diagram of low–end UCMM server . 172
Figure 31 – Sequence diagram for a UCMM with one outstanding message . 174
Figure 32 – Sequence diagram for a UCMM with multiple outstanding messages . 175
Figure 33 – TPDU buffer . 176
Figure 34 – Data flow diagram using a client transport class 0 and server transport
class 0 . 179
Figure 35 – Sequence diagram of data transfer using transport class 0. 179

– 4 – 61158-6-2  IEC:2010
Figure 36 – Class 0 client STD . 180
Figure 37 – Class 0 server STD . 181
Figure 38 – Data flow diagram using client transport class 1 and server transport
class 1 . 182
Figure 39 – Sequence diagram of data transfer using client transport class 1 and
server transport class 1 . 183
Figure 40 – Class 1 client STD . 185
Figure 41 – Class 1 server STD . 186
Figure 42 – Data flow diagram using client transport class 2 and server transport
class 2 . 188
Figure 43 – Diagram of data transfer using client transport class 2 and server transport
class 2 without returned data . 189
Figure 44 – Sequence diagram of data transfer using client transport class 2 and
server transport class 2 with returned data . 190
Figure 45 – Class 2 client STD . 191
Figure 46 – Class 2 server STD . 193
Figure 47 – Data flow diagram using client transport class 3 and server transport
class 3 . 196
Figure 48 – Sequence diagram of data transfer using client transport class 3 and
server transport class 3 without returned data . 197
Figure 49 – Sequence diagram of data transfer using client transport class 3 and
server transport class 3 with returned data . 198
Figure 50 – Class 3 client STD . 200
Figure 51 – Class 3 server STD . 203
Figure 52 – Data flow diagram using transport classes 4 and 5 . 205
Figure 53 – Sequence diagram of message exchange using transport classes 4 and 5 . 206
Figure 54 – Sequence diagram of messages overwriting each other . 207
Figure 55 – Sequence diagram of queued message exchange using transport classes
4 and 5 . 208
Figure 56 – Sequence diagram of retries using transport classes 4 and 5 . 208
Figure 57 – Sequence diagram of idle traffic using transport classes 4 and 5 . 209
Figure 58 – Classes 4 and 5 basic structure . 210
Figure 59 – Class 6 basic structure . 211
Figure 60 – Classes 4 to 6 general STD . 212
Figure 61 – Class 4 sender STD . 214
Figure 62 – Class 4 receiver STD . 217
Figure 63 – Sequence diagram of three fragments using transport class 5 . 220
Figure 64 – Sequence diagram of fragmentation with retries using transport class 5 . 221
Figure 65 – Sequence diagram of two fragments using transport class 5 . 221
Figure 66 – Sequence diagram of aborted message using transport class 5 . 222
Figure 67 – Class 5 sender STD . 223
Figure 68 – Class 5 receiver STD . 226
Figure 69 – Data flow diagram for transport class 6 . 231
Figure 70 – Sequence diagram of message exchange using transport class 6 . 233
Figure 71 – Sequence diagram of retries using transport class 6 . 233
Figure 72 – Sequence diagram of idle traffic using transport class 6 . 234

61158-6-2  IEC:2010 – 5 –
Figure 73 – Sequence diagram of request overwriting null . 235
Figure 74 – Sequence diagram of response overwriting ACK of null . 235
Figure 75 – Sequence diagram of three fragments using transport class 6 . 236
Figure 76 – Sequence diagram of fragmentation with retries using transport class 6 . 237
Figure 77 – Sequence diagram of two fragments using transport class 6 . 237
Figure 78 – Sequence diagram of aborted fragmented sequence using transport
class 6 . 238
Figure 79 – Class 6 client STD . 239
Figure 80 – Class 6 server STD . 242
Figure 81 – Data flow diagram for a link producer and consumer . 247
Figure 82 – State transition diagram for a link producer . 250
Figure 83 – State transition diagram for a link consumer . 251
Figure 84 – DS field in the IP header . 261
Figure 85 – IEEE 802.1Q tagged frame . 261

Table 1 – Get_Attribute_All response service rules . 26
Table 2 – Example class level object/service specific response data of
Get_Attribute_All . 26
Table 3 – Example Get_Attribute_All data array method . 27
Table 4 – Set_Attribute_All request service rules . 28
Table 5 – Example Set_Attribute_All attribute ordering method . 28
Table 6 – Example Set_Attribute_All data array method . 28
Table 7 – State event matrix format . 30
Table 8 – Example state event matrix . 30
Table 9 – UCMM_PDU header format . 33
Table 10 – UCMM command codes . 33
Table 11 – Transport class 0 header . 34
Table 12 – Transport class 1 header . 35
Table 13 – Transport class 2 header . 35
Table 14 – Transport class 3 header . 35
Table 15 – Classes 4 to 6 header format . 35
Table 16 – Real-time data header – exclusive owner . 36
Table 17 – Real-time data header– redundant owner . 37
Table 18 – Forward_Open request format . 39
Table 19 – Forward_Open_Good response format . 40
Table 20 – Forward_Open_Bad response format . 40
Table 21 – Large_Forward_Open request format . 41
Table 22 – Large_Forward_Open_Good response format . 42
Table 23 – Large_Forward_Open_Bad response format . 42
Table 24 – Forward_Close request format . 43
Table 25 – Forward_Close_Good response format . 43
Table 26 – Forward_Close_Bad response format . 44
Table 27 – Unconnected_Send request format . 45
Table 28 – Unconnected_Send_Good response format . 45

– 6 – 61158-6-2  IEC:2010
Table 29 – Unconnected_Send_Bad response format . 46
Table 30 – Get_Connection_Data request format . 46
Table 31 – Get_Connection_Data response format . 47
Table 32 – Search_Connection_Data request format . 47
Table 33 – Get_Object_Owner request format . 48
Table 34 – Forward_Open_Good response format . 48
Table 35 – Time-out multiplier . 51
Table 36 – Time tick units . 51
Table 37 – Selection of connection ID . 55
Table 38 – Transport class, trigger and Is_Server format . 55
Table 39 – MR_Request_Header format . 56
Table 40 – MR_Response_Header format . 56
Table 41 – Structure of Get_Attribute_All_ResponsePDU body . 57
Table 42 – Structure of Set_Attribute_All_RequestPDU body . 57
Table 43 – Structure of Get_Attribute_List_RequestPDU body . 57
Table 44 – Structure of Get_Attribute_List_ResponsePDU body . 57
Table 45 – Structure of Set_Attribute_List_RequestPDU body . 57
Table 46 – Structure of Set_Attribute_List_ResponsePDU body . 58
Table 47 – Structure of Reset_RequestPDU body . 58
Table 48 – Structure of Reset_ResponsePDU body . 58
Table 49 – Structure of Start_RequestPDU body . 58
Table 50 – Structure of Start_ResponsePDU body . 58
Table 51 – Structure of Stop_RequestPDU body . 59
Table 52 – Structure of Stop_ResponsePDU body . 59
Table 53 – Structure of Create_RequestPDU body . 59
Table 54 – Structure of Create_ResponsePDU body . 59
Table 55 – Structure of Delete_RequestPDU body . 59
Table 56 – Structure of Delete_ResponsePDU body . 59
Table 57 – Structure of Get_Attribute_Single_ResponsePDU body . 60
Table 58 – Structure of Set_Attribute_Single_RequestPDU body . 60
Table 59 – Structure of Set_Attribute_Single_ResponsePDU body . 60
Table 60 – Structure of Find_Next_Object_Instance_RequestPDU body . 60
Table 61 – Structure of Find_Next_Object_Instance_ResponsePDU body . 60
Table 62 – Structure of Apply_Attributes_RequestPDU body . 61
Table 63 – Structure of Apply_Attributes_ResponsePDU body . 61
Table 64 – Structure of Save_RequestPDU body . 61
Table 65 – Structure of Save_ResponsePDU body . 61
Table 66 – Structure of Restore_RequestPDU body . 61
Table 67 – Structure of Restore_ResponsePDU body . 61
Table 68 – Structure of Group_Sync_RequestPDU body . 62
Table 69 – Structure of Group_Sync_ResponsePDU body . 62
Table 70 – Identity object class attributes . 62
Table 71 – Identity object instance attributes . 62

61158-6-2  IEC:2010 – 7 –
Table 72 – Identity object bit definitions for status instance attribute . 63
Table 73 – Bits 4 – 7 of status instance attribute . 64
Table 74 – Class level object/service specific response data of Get_Attribute_All . 64
Table 75 – Instance level object/service specific response data of Get_Attribute_All . 65
Table 76 – Modified instance level object/service specific response data of
Get_Attribute_All . 65
Table 77 – Object-specific parameter for Reset . 66
Table 78 – Message Router object class attributes . 66
Table 79 – Message Router object instance attributes . 66
Table 80 – Class level object/service specific response data of Get_Attribute_All . 67
Table 81 – Instance level object/service specific response data of Get_Attribute_All . 67
Table 82 – Assembly object class attributes . 67
Table 83 – Assembly object instance attributes . 67
Table 84 – Acknowledge Handler object class attributes . 68
Table 85 – Acknowledge Handler object instance attributes . 69
Table 86 – Structure of Add_AckData_Path_RequestPDU body . 69
Table 87 – Structure of Remove_AckData_Path_RequestPDU body . 69
Table 88 – Time Sync object instance attributes . 70
Table 89 – ClockIdentity encoding for different network implementations . 73
Table 90 – ClockClass values . 73
Table 91 – TimeAcuracy values . 74
Table 92 – TimePropertyFlags bit values . 74
Table 93 – TimeSource values . 75
Table 94 – Types of Clock . 75
Table 95 – Parameter object class attributes . 75
Table 96 – Parameter Class Descriptor bit values . 76
Table 97 – Parameter object instance attributes . 77
Table 98 – Semantics of Descriptor Instance attribute . 77
Table 99 – Minimum and Maximum Value semantics . 79
Table 100 – Scaling Formula attributes . 80
Table 101 – Scaling links . 80
Table 102 – Structure of Get_Enum_String_RequestPDU body . 81
Table 103 – Structure of Get_Enum_String_ResponsePDU body . 81
Table 104 – Enumerated strings Type versus Parameter data type . 81
Table 105 – Connection Manager object class attributes . 82
Table 106 – Connection Manager object instance attributes . 82
Table 107 – Connection object class attributes . 83
Table 108 – Connection object instance attributes . 84
Table 109 – Values assigned to the state attribute . 85
Table 110 – Values assigned to the instance_type attribute . 85
Table 111 – Possible values within Direction Bit . 86
Table 112 – Possible values within Production Trigger Bits . 86
Table 113 – Possible values within Transport Class Bits . 87

– 8 – 61158-6-2  IEC:2010
Table 114 – Transport Class_Trigger attribute . 88
Table 115 – Values defined for the CP2/3_produced_connection_id attribute . 88
Table 116 – Values defined for the CP2/3_consumed_connection_id attribute . 89
Table 117 – Values for the Initial Production Characteristics nibble . 90
Table 118 – Values for the Initial Consumption Characteristics nibble . 91
Table 119 – Values for the watchdog_timeout_action. 94
Table 120 – Structure of Connection_Bind_RequestPDU body . 95
Table 121 – Object specific status for Connection_Bind service . 96
Table 122 – Structure of Producing_Application_Lookup_RequestPDU body . 96
Table 123 – Structure of Producing_Application_Lookup_ResponsePDU body . 96
Table 124 – Producing_Application_Lookup Service status codes . 96
Table 125 – Possible port segment examples . 98
Table 126 – TCP/IP link address examples . 99
Table 127 – Electronic key segment format . 101
Table 128 – Logical segments examples . 102
Table 129 – Network segments . 102
Table 130 – Extended subtype definitions . 104
Table 131 – Data segment . 104
Table 132 – ANSI_Extended_Symbol segment . 105
Table 133 – Addressing categories . 105
Table 134 – Class code ID ranges . 106
Table 135 – Attribute ID ranges . 106
Table 136 – Service code ranges . 106
Table 137 – Class codes . 107
Table 138 – Reserved class attributes for all object class definitions . 107
Table 139 – Common services list . 108
Table 140 – Acknowledge Handler object specific services list . 109
Table 141 – Parameter object specific services list . 109
Table 142 – Services specific to Connection Manager . 109
Table 143 – Services specific to Connection object . 109
Table 144 – Device type numbering . 110
Table 145 – Connection Manager service request error codes . 111
Table 146 – General status codes . 116
Table 147 – Identity object status codes . 118
Table 148 – Encapsulation header . 125
Table 149 – Encapsulation command codes . 125
Table 150 – Encapsulation status codes . 126
Table 151 – Options flags . 127
Table 152 – Nop request encapsulation header . 127
Table 153 – RegisterSession request encapsulation header . 127
Table 154 – RegisterSession request data portion . 128
Table 155 – Options flags . 128
Table 156 – RegisterSession reply encapsulation header . 128

61158-6-2  IEC:2010 – 9 –
Table 157 – RegisterSession reply data portion . 128
Table 158 – UnRegisterSession request encapsulation header . 129
Table 159 – ListServices request encapsulation header . 129
Table 160 – ListServices reply encapsulation header . 130
Table 161 – ListServices reply data portion. 130
Table 162 – Service type codes . 130
Table 163 – Communications capability flags . 130
Table 164 – ListIdentity request encapsulation header . 131
Table 165 – ListIdentity reply encapsulation header . 131
Table 166 – ListIdentity reply data portion . 132
Table 167 – ListInterfaces request encapsulation header . 132
Table 168 – ListInterfaces reply encapsulation header . 133
Table 169 – SendRRData request encapsulation header . 133
Table 170 – SendRRData request data portion . 133
Table 171 – SendRRData reply encapsulation header . 134
Table 172 – SendUnitData request encapsulation header . 134
Table 173 – SendUnitData request data portion . 135
Table 174 – Common packet format . 135
Table 175 – Address and data item structure . 135
Table 176 – Address type ID’s . 135
Table 177 – Data type ID’s . 136
Table 178 – Null address type . 136
Table 179 – Connected address type . 136
Table 180 – Sequenced address type . 137
Table 181 – UCMM data type .
...