IEC TR 62453-52-150:2017

IEC TR 62453-52-150 ®
Edition 1.0 2017-06
TECHNICAL
REPORT
colour
inside
Field device tool (FDT) interface specification –
Part 52-150: Communication implementation for common language
infrastructure – IEC 61784 CPF 15

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IEC TR 62453-52-150 ®
Edition 1.0 2017-06
TECHNICAL
REPORT
colour
inside
Field device tool (FDT) interface specification –

Part 52-150: Communication implementation for common language

infrastructure – IEC 61784 CPF 15

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.05; 35.110 ISBN 978-2-8322-4336-7

– 2 – IEC TR 62453-52-150:2017 © IEC 2017
CONTENTS
FOREWORD . 8
INTRODUCTION . 10
1 Scope . 11
2 Normative references . 11
3 Terms, definitions, symbols, abbreviated terms and conventions . 12
3.1 Terms and definitions . 12
3.2 Symbols and abbreviated terms . 12
3.3 Conventions . 12
3.3.1 Datatype names and references to datatypes . 12
3.3.2 Vocabulary for requirements . 12
3.3.3 Use of UML . 12
4 Bus category . 12
5 Access to instance and device data . 12
5.1 General . 12
5.2 IO signals provided by DTM . 13
5.3 Data interfaces . 13
5.3.1 Common data set . 13
5.3.2 Mapping of Modbus datatypes to FDT datatypes . 13
5.3.3 SemanticInfo . 13
6 Protocol specific behaviour . 14
6.1 Modbus data and addressing model . 14
6.2 Modbus-related information of a Device DTM . 15
6.3 Broadcasting . 15
6.4 Unconfirmed private Modbus request . 16
7 Protocol specific usage of general datatypes . 16
8 Protocol specific common datatype: ModbusDeviceAddress . 17
9 Network management datatypes . 18
9.1 General . 18
9.2 Configuration . 19
9.3 Process Data Items . 19
9.4 Parameterization . 19
10 Communication datatypes . 19
10.1 General . 19
10.2 ModbusConnectRequest . 19
10.3 ModbusConnectResponse . 20
10.4 ModbusDisconnectRequest . 20
10.5 ModbusDisconnectResponse . 21
10.6 ModbusAbortMessage. 21
10.7 ModbusReadCoilsRequest . 22
10.8 ModbusReadCoilsResponse . 23
10.9 ModbusReadDiscreteInputsRequest . 24
10.10 ModbusReadDiscreteInputsResponse . 24
10.11 ModbusReadHoldingRegistersRequest . 25
10.12 ModbusReadHoldingRegistersResponse . 26
10.13 ModbusReadInputRegistersRequest . 27
10.14 ModbusReadInputRegistersResponse . 28

10.15 ModbusWriteSingleCoilRequest . 29
10.16 ModbusWriteSingleCoilResponse . 30
10.17 ModbusWriteSingleRegisterRequest . 30
10.18 ModbusWriteSingleRegisterResponse. 31
10.19 ModbusReadExceptionStatusRequest . 32
10.20 ModbusReadExceptionStatusResponse . 32
10.21 ModbusDiagnosticsRequest . 33
10.22 ModbusDiagnosticsResponse . 34
10.23 ModbusGetCommEventCounterRequest . 35
10.24 ModbusGetCommEventCounterResponse . 35
10.25 ModbusGetCommEventLogRequest . 36
10.26 ModbusGetCommEventLogResponse . 37
10.27 lModbusWriteMultipleCoilsRequest . 38
10.28 ModbusWriteMultipleCoilsResponse . 39
10.29 ModbusWriteMultipleRegistersRequest . 39
10.30 ModbusWriteMultipleRegistersResponse . 40
10.31 ModbusReportSlaveIDRequest . 41
10.32 ModbusReportSlaveIDResponse . 41
10.33 ModbusReadFileRecordRequest . 42
10.34 ModbusReadFileSubRequest . 43
10.35 ModbusReadFileRecordResponse . 44
10.36 ModbusReadFileSubResponse . 45
10.37 ModbusWriteFileRecordRequest . 45
10.38 ModbusWriteFileSubRequest . 46
10.39 ModbusWriteFileRecordResponse . 47
10.40 ModbusMaskWriteRegisterRequest . 47
10.41 ModbusMaskWriteRegisterResponse . 48
10.42 ModbusReadWriteRegistersRequest . 49
10.43 ModbusReadWriteRegistersResponse . 50
10.44 ModbusReadFiFoQueueRequest. 51
10.45 ModbusReadFiFoQueueResponse . 52
10.46 ModbusEncapsulatedInterfaceTransportRequest . 53
10.47 ModbusEncapsulatedInterfaceTransportResponse . 53
10.48 ModbusReadDeviceIdentificationRequest . 54
10.49 ModbusReadDeviceIdentificationResponse . 55
10.50 ModbusPrivateRequest . 58
10.51 ModbusPrivateResponse . 58
10.52 ModbusUnconfirmedPrivateRequest . 59
10.53 ModbusUnconfirmedPrivateResponse . 60
10.54 ModbusExceptionResponse . 61
11 Datatypes for process data information . 62
11.1 General . 62
11.2 ModbusIOSignalInfo . 62
11.3 Mapping of Modbus datatypes to FDT datatypes . 63
12 Device identification . 63
12.1 General . 63
12.2 ModbusDeviceScanInfo datatype . 63
12.3 ModbusDeviceIdentInfo datatype . 64
12.4 Mapping of Information Source . 66

– 4 – IEC TR 62453-52-150:2017 © IEC 2017
Bibliography . 68

Figure 1 – Part 52-150 of the IEC 62453 series . 10
Figure 2 – Modbus data and addressing model . 15
Figure 3 – ModbusDeviceAddress . 17
Figure 4 – ModbusNetworkData . 18
Figure 5 – ModbusConnectRequest . 19
Figure 6 – ModbusConnectResponse . 20
Figure 7 – ModbusDisconnectRequest . 21
Figure 8 – ModbusDisconnectResponse . 21
Figure 9 – ModbusAbortMessage . 22
Figure 10 – ModbusReadCoilsRequest . 22
Figure 11 – ModbusReadCoilsResponse . 23
Figure 12 – ModbusReadDiscreteInputsRequest . 24
Figure 13 – ModbusReadDiscreteInputsResponse . 25
Figure 14 – ModbusReadHoldingRegistersRequest. 26
Figure 15 – ModbusReadHoldingRegistersResponse . 27
Figure 16 – ModbusReadInputRegistersRequest. 28
Figure 17 – ModbusReadInputRegistersResponse . 28
Figure 18 – ModbusWriteSingleCoilRequest . 29
Figure 19 – ModbusWriteSingleCoilResponse . 30
Figure 20 – ModbusWriteSingleRegisterRequest . 31
Figure 21 – ModbusWriteSingleRegisterResponse . 31
Figure 22 – ModbusReadExceptionStatusRequest . 32
Figure 23 – ModbusReadExceptionStatusResponse . 33
Figure 24 – ModbusDiagnosticsRequest . 34
Figure 25 – ModbusDiagnosticsResponse . 34
Figure 26 – ModbusGetCommEventCounterRequest . 35
Figure 27 – ModbusGetCommEventCounterResponse . 36
Figure 28 – ModbusGetCommEventLogRequest . 37
Figure 29 – ModbusGetCommEventLogResponse . 37
Figure 30 – ModbusWriteMultipleCoilsRequest . 38
Figure 31 – ModbusWriteMultipleCoilsResponse . 39
Figure 32 – ModbusWriteMultipleRegistersRequest . 40
Figure 33 – ModbusWriteMultipleRegistersResponse . 40
Figure 34 – ModbusReportSlaveIDRequest . 41
Figure 35 – ModbusReportSlaveIDResponse . 42
Figure 36 – ModbusReadFileRecordRequest . 43
Figure 37 – ModbusReadFileSubRequest . 43
Figure 38 – ModbusReadFileRecordResponse . 44
Figure 39 – ModbusReadFileSubResponse . 45
Figure 40 – ModbusWriteFileRecordRequest . 46
Figure 41 – ModbusWriteFileSubRequest . 46

Figure 42 – ModbusWriteFileRecordResponse . 47
Figure 43 – ModbusMaskWriteRegisterRequest . 48
Figure 44 – ModbusMaskWriteRegisterResponse . 49
Figure 45 – ModbusReadWriteRegistersRequest . 50
Figure 46 – ModbusReadWriteRegistersResponse . 51
Figure 47 – ModbusReadFiFoQueueRequest . 52
Figure 48 – ModbusReadFiFoQueueResponse . 52
Figure 49 – ModbusEncapsulatedInterfaceTransportRequest . 53
Figure 50 – ModbusEncapsulatedInterfaceTransportResponse . 54
Figure 51 – ModbusReadDeviceIdentificationRequest . 55
Figure 52 – ModbusReadDeviceIdentificationResponse . 56
Figure 53 – ModbusIdentificationObject . 56
Figure 54 – ModbusPrivateRequest . 58
Figure 55 – ModbusPrivateResponse . 59
Figure 56 – ModbusUnconfirmedPrivateRequest . 60
Figure 57 – ModbusUnconfirmedPrivateResponse . 60
Figure 58 – ModbusExceptionResponse . 61
Figure 59 – ModbusIOSignalInfo . 62
Figure 60 – ModbusDeviceScanInfo . 64
Figure 61 – ModbusDeviceIdentInfo . 65

Table 1 – Mapping of datatypes . 13
Table 2 – Usage of general datatypes . 14
Table 3 – Usage of broadcasts in transaction requests . 16
Table 4 – Protocol specific usage of general datatypes . 17
Table 5 – ModbusDeviceAddress . 18
Table 6 – ModbusDeviceSerialAddress . 18
Table 7 – ModbusDeviceTcpAddress . 18
Table 8 – Modbus Network Data . 19
Table 9 – ModbusConnectRequest datatype . 20
Table 10 – ModbusConnectResponse datatype . 20
Table 11 – ModbusDisconnectRequest datatype . 21
Table 12 – ModbusDisconnectResponse datatype . 21
Table 13 – ModbusAbortMessage datatype . 22
Table 14 – ModbusReadCoilsRequest datatype . 23
Table 15 – ModbusReadCoilsResponse datatype . 23
Table 16 – ModbusReadDiscreteInputsRequest datatype . 24
Table 17 – ModbusReadDiscreteInputsResponse datatype . 25
Table 18 – ModbusReadHoldingRegistersRequest datatype . 26
Table 19 – ModbusReadHoldingRegistersResponse datatype . 27
Table 20 – ModbusReadInputRegistersRequest datatype . 28
Table 21 – ModbusReadInputRegistersResponse datatype . 29
Table 22 – ModbusWriteSingleCoilRequest datatype . 29

– 6 – IEC TR 62453-52-150:2017 © IEC 2017
Table 23 – ModbusWriteSingleCoilResponse datatype . 30
Table 24 – ModbusWriteSingleRegisterRequest datatype . 31
Table 25 – ModbusWriteSingleRegisterResponse datatype . 32
Table 26 – ModbusReadExceptionStatusRequest datatype . 32
Table 27 – ModbusReadExceptionStatusResponse datatype . 33
Table 28 – ModbusDiagnosticsRequest datatype . 34
Table 29 – ModbusDiagnosticsResponse datatype . 35
Table 30 – ModbusGetCommEventCounterRequest datatype . 35
Table 31 – ModbusGetCommEventCounterResponsedatatype . 36
Table 32 – ModbusGetCommEventLogRequest datatype . 37
Table 33 – ModbusGetCommEventLogResponse datatype . 38
Table 34 – ModbusWriteMultipleCoilsRequest datatype . 39
Table 35 – ModbusWriteMultipleCoilsResponse datatype . 39
Table 36 – ModbusWriteMultipleRegistersRequest datatype . 40
Table 37 – ModbusWriteMultipleRegistersResponse . 41
Table 38 – ModbusReportSlaveIDRequest datatype . 41
Table 39 – ModbusReportSlaveIDResponse . 42
Table 40 – ModbusReadFileRecordRequest datatype . 43
Table 41 – ModbusReadFileSubRequest datatype . 44
Table 42 – ModbusReadFileRecordResponse . 45
Table 43 – ModbusReadFileSubResponse . 45
Table 44 – ModbusWriteFileRecordRequest datatype . 46
Table 45 – ModbusWriteFileSubRequest datatype . 47
Table 46 – ModbusWriteFileRecordResponse . 47
Table 47 – ModbusMaskWriteRegisterRequest datatype . 48
Table 48 – ModbusMaskWriteRegisterResponse . 49
Table 49 – ModbusReadWriteRegistersRequest datatype . 50
Table 50 – ModbusReadWriteRegistersResponse . 51
Table 51 – ModbusReadFiFoQueueRequest datatype . 52
Table 52 – ModbusReadFiFoQueueResponse . 53
Table 53 – ModbusEncapsulatedInterfaceTransportRequest datatype . 53
Table 54 – ModbusEncapsulatedInterfaceTransportResponse . 54
Table 55 – ModbusReadDeviceIdentificationRequest datatype . 55
Table 56 – ModbusReadDeviceIdentificationResponse . 57
Table 57 – ModbusIdentificationObject . 58
Table 58 – ModbusPrivateRequest datatype . 58
Table 59 – ModbusPrivateResponse . 59
Table 60 – ModbusUnconfirmedPrivateRequest datatype . 60
Table 61 – ModbusUnconfirmedPrivateResponse . 61
Table 62 – ModbusExceptionResponse. 62
Table 63 – ModbusIOSignalInfo datatype . 63
Table 64 – ModbusDeviceScanInfo datatype . 64
Table 65 – ModbusDeviceIdentInfo datatype . 65

Table 66 – Protocol specific mapping of scan information . 66
Table 67 – Profile specific mapping of identification information . 67

– 8 – IEC TR 62453-52-150:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIELD DEVICE TOOL (FDT) INTERFACE SPECIFICATION –

Part 52-150: Communication implementation
for common language infrastructure –
IEC 61784 CPF 15
FOREWORD
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 62453-52-150, which is a technical report, has been prepared by subcommittee 65E:
Devices and integration in enterprise systems, of IEC technical committee 65: Industrial-
process measurement, control and automation.
Each part of the IEC 62453-52-xy series is intended to be read in conjunction with its
corresponding part in the IEC 62453-3xy series. This document corresponds to
IEC 63453-315.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
65E/440/DTR 65E/514/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
The list of all parts of the IEC 62453 series, under the general title Field device tool (FDT)
interface specification, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 10 – IEC TR 62453-52-150:2017 © IEC 2017
INTRODUCTION
This part of IEC 62453 is an interface specification for developers of Field Device Tool (FDT)
components for function control and data access within a client/server architecture. The
specification is a result of an analysis and design process to develop standard interfaces to
facilitate the development of servers and clients by multiple vendors that need to interoperate
seamlessly.
With the integration of fieldbuses into control systems, there are a few other tasks which need
to be performed. In addition to fieldbus- and device-specific tools, there is a need to integrate
these tools into higher-level system-wide planning or engineering tools. In particular, for use
in extensive and heterogeneous control systems, typically in the area of the process industry,
the unambiguous definition of engineering interfaces that are easy to use for all those
involved is of great importance.
A device-specific software component, called Device Type Manager (DTM), is supplied by the
field device manufacturer with its device. The DTM is integrated into engineering tools via the
FDT interfaces defined in this specification. The approach to integration is in general open for
all kind of fieldbusses and thus meets the requirements for integrating different kinds of
devices into heterogeneous control systems.
Figure 1 shows how this part of the IEC 62453-52-xy series is aligned in the structure of the
IEC 62453 series.
Part 52-150
Communication
implementation for
common language
infrastructure –
IEC 61784 CPF 15
IEC
Figure 1 – Part 52-150 of the IEC 62453 series

FIELD DEVICE TOOL (FDT) INTERFACE SPECIFICATION –

Part 52-150: Communication implementation
for common language infrastructure –
IEC 61784 CPF 15
1 Scope
This part of the IEC 62453-52-xy series, which is a Technical Report, provides information for
technology into the CLI-based implementation of FDT interface
integrating the Modbus®
specification (IEC TR 62453-42).
This part of IEC 62453 specifies the implementation of communication and other services
based on IEC 62453-315.
This document neither contains the FDT specification nor modifies it.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 61131-3:2013, Programmable controllers – Part 3: Programming languages
IEC 61158-5-15:2010, Industrial communication networks – Fieldbus specifications –
Part 5-15: Application layer service definition – Type 15 elements
IEC 61784-1:2014, Industrial communication networks – Profiles – Part 1: Fieldbus profiles
IEC 62453-1:2016, Field device tool (FDT) interface specification – Part 1: Overview and
guidance
IEC 62453-2:2016, Field device tool (FDT) interface specification – Part 2: Concepts and
detailed description
IEC TR 62453-42:2016, Field device tool (FDT) interface specification – Part 42: Object model
integration profile – Common language infrastructure
IEC 62453-315:2009, Field device tool (FDT) interface specification – Part 315:
Communication profile integration – IEC 61784 CPF 15
IEC 62453-315:2009/AMD1:2016
___________
Modbus is the trademark of Schneider Automation Inc. It is registered in the United States of America. This
information is given for the convenience of users of this document and does not constitute an endorsement by
IEC of the trademark holder or any of its products. Compliance to this profile does not require use of the
trademark Modbus. Use of the trademark Modbus requires permission from Schneider Automation Inc.

– 12 – IEC TR 62453-52-150:2017 © IEC 2017
3 Terms, definitions, symbols, abbreviated terms and conventions
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62453-1,
IEC 62453-2, IEC TR 62453-42 and IEC 62453-315 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.2 Symbols and abbreviated terms
For the purposes of this document, the symbols and abbreviations given in IEC 62453-1,
IEC 62453-2, IEC 62453-315, IEC TR 62453-42 and the following apply.
IO Input/Output
3.3 Conventions
3.3.1 Datatype names and references to datatypes
The conventions for naming and referencing of datatypes are explained in IEC 62453-2:2016,
Clause A.1.
3.3.2 Vocabulary for requirements
The following expressions are used when specifying requirements.
Usage of “shall” or “mandatory” No exceptions allowed.
Usage of “should” or “recommended” Strong recommendation. It may make sense
in special exceptional cases to differ from the
described behaviour.
Usage of “can” or “optional” Function or behaviour may be provided,
depending on defined conditions.
3.3.3 Use of UML
Figures in this document are using UML notation as defined in Annex A of IEC 62453-1:2016.
4 Bus category
IEC 61784 CPF 15 protocol is identified in the attribute busCategory of the BusCategory
element by the identifiers, as specified in IEC 62453-315.
5 Access to instance and device data
5.1 General
The minimum set of provided data shall be:
• All process values available for the device shall be modeled as ProcessData including the
ranges and scaling if applicable;
• All network configuration related parameters shall be exposed in NetworkData (see
Clause 9).
5.2 IO signals provided by DTM
A DTM shall provide IO signal information for the device using the IProcessData interface.
The IO signals describe datatype and address parameters of process data as detailed in 11.2.
5.3 Data interfaces
5.3.1 Common data set
For Modbus no minimum set of parameters or common data set is defined which shall be
provided by a DTM. Exposure of device parameters is at the vendor’s discretion. If a DTM
provides process values, the process variables shall be modelled as process data objects.
5.3.2 Mapping of Modbus datatypes to FDT datatypes
Modbus uses datatypes as specified in [2] for the transmission on the fieldbus. The FDT
interfaces IDeviceData and IInstanceData use .NET datatypes, while PLC applications use
datatypes defined in IEC 61131-3. This subclause defines the mapping of parameter
datatypes, whereas mapping of process datatypes is defined in 11.3.
The mapping of parameter datatypes is described in Table 1.
Table 1 – Mapping of datatypes
Modbus datatype FDT datatype IEC 61131 datatype
Discrete Inputs BitArray ARRAY [] OF BOOL
Coil bool BOOL
Coils BitArray ARRAY [] OF BOOL
Input Registers ushort[] ARRAY [] OF WORD
Holding Register ushort WORD
Holding Registers ushort[] ARRAY [] OF WORD

The FDT data types do not change any byte or bit order of the data. The data interpretation,
e.g. if a float value is transferred in a holding register, is under the responsibility of the DTM
respectively the user of the data. The user of the data shall know how the data is represented
by the hardware device.
5.3.3 SemanticInfo
The usage of the SemanticInfo datatype is shown in Table 2. The identifier in SemanticId shall
be unique and always reference the same element. This means the semantic information shall
be the same whenever the same data is referenced. By using this attribute e.g. a Frame
Application is able to get the information regarding the meaning and usage of a single data
structure.
___________
Figures in square backets refer to the Bibliography.

– 14 – IEC TR 62453-52-150:2017 © IEC 2017
Table 2 – Usage of general datatypes
Attribute Description for use in Modbus
SemanticInfo.ParameterReadAddress The value of ParameterReadAddress and ParameterWriteAdress is a
/ string conforming to a pattern as follows:
SemanticInfo.ParameterWriteAddress
FunctionCode.StartAddress.BitOffset.BitLength
where
FunctionCode = Modbus function code to access the data
StartAddress = starting address
BitOffset = start bit within the starting address
BitLength = length in bits
All values are unsigned integers.
SemanticInfo.ApplicationDomain The value of ApplicationDomain is as follows:
MODBUS
SemanticInfo.SemanticId The value of SemanticId is vendor specific.

6 Protocol specific behaviour
6.1 Modbus data and addressing model
The Modbus data model is very simple and described in [2]. Figure 2 shows an extract of the
data model description.
----
...