Ethernet POWERLINK
Dynamic Node Allocation
EPSG DS 302-E V1.2.1

EPSG Draft Standard 302-E

Ethernet POWERLINKPart E: Dynamic Node Allocation

Version 1.2.1©

B&R(B&R Industrial Automation GmbH)
2023

EPSG DS 302-E V1.2.1-2-

B&R Industrial Automation GmbH

POWERLINK-Office
B&R Straße 15142 Eggelsberg
Austria

powerlink.office@br-automation.com
www.br-automation.com/en/technologies/powerlink/

The EPSG Draft Standard 302-E “Ethernet Powerlink, Part E: Dynamic Node Allocation” has been
provided by Ethernet POWERLINK Standardisation Group (hereinafter referred to as “EPSG”). As aconsequence of the EPSG being dissolved from March 31st, 2023, B&R Industrial Automation GmbHwill – as the formal successor of EPSG regarding the rights and content – make the Ethernet Powerlink
Part E: Dynamic Node Allocation available as open source on it’s own website subject to the conditions
mentioned in the disclaimer under clause Pre. 1 of this document. B&R Industrial Automation GmbHespecially disclaims liability for any personal injury, property or other damage, of any nature whatsoever,whether special, indirect, consequential, or compensatory, directly or indirectly resulting from thepublication, use of, or reliance upon this, or any other EPSG Standard document.

EPSG DS 302-E V1.2.1

Pre. 1-3-Disclaimer

Use of this EPSG Standard is wholly voluntary. The EPSG disclaims liability for any personal injury,
property or other damage, of any nature whatsoever, whether special, indirect, consequential, orcompensatory, directly or indirectly resulting from the publication, use of, or reliance upon this, or any
other EPSG Standard document.
The EPSG does not warrant or represent the accuracy or content of the material contained herein, andexpressly disclaims any express or implied warranty, including any implied warranty of merchantability
or fitness for a specific purpose, or that the use of the material contained herein is free from patent
infringement. EPSG Standards documents are supplied “AS IS”.
The existence of an EPSG Standard does not imply that there are no other ways to produce, test,
measure, purchase, market, or provide other goods and services related to the scope of the EPSG
Standard. Furthermore, the viewpoint expressed at the time a standard is approved and issued is subject
to change brought about through developments in the state of the art and comments received fromusers of the standard. Users are cautioned to check to determine that they have the latest edition of any
EPSG Standard.
In publishing and making this document available, the EPSG is not suggesting or rendering professionalor other services for, or on behalf of, any person or entity. Nor is the EPSG undertaking to perform any
duty owed by any other person or entity to another. Any person utilizing this, and any other EPSG
Standards document, should rely upon the advice of a competent professional in determining theexercise of reasonable care in any given circumstances.
Interpretations: Occasionally questions may arise regarding the meaning of portions of standards as
they relate to specific applications. When the need for interpretations is brought to the attention of the
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a consensus of concerned interests, it is important to ensure that any interpretation has also received
the concurrence of a balance of interests. For this reason, the EPSG and its members are not able toprovide an instant response to interpretation requests except in those cases where the matter has
previously received formal consideration.
Comments for revision of EPSG Standards are welcome from any interested party, regardless ofmembership affiliation with the EPSG. Suggestions for changes in documents should be in the form ofa proposed change of text, together with appropriate supporting comments. Comments on standards
and requests for interpretations should be sent to the address given on the page before .

Pre. 1.1

Patent noticeAttention is called to the possibility that implementation of this standard may require use of subject
matter covered by patent rights. By publication of this standard, no position is taken with respect to theexistence or validity of any patent rights in connection therewith. B&R shall not be responsible for
identifying patents for which a license may be required by an EPSG standard or for conducting inquiries
into the legal validity or scope of those patents that are brought to its attention.

EPSG DS 302-E V1.2.1-4-Pre. 2

History

Vers.
0.0.1
0.0.2
0.0.3
0.1.0
1.0.0

Date
2010-01-14
2010-10-29
2013-01-08
2013-03-29
2013-12-18

AuthorStephan Kirchmayer
Stephan Kirchmayer
Stephan Kirchmayer
Stephan Kirchmayer
Stephan Kirchmayer

B&R
B&R
B&R
B&R
B&R

1.0.1

2015-12-20

Stephan Kirchmayer

B&R

1.1.0
1.1.1
1.1.2

2016-03-14
2018-10-17
2019-01-08

Stephan Kirchmayer
Stephan Kirchmayer
Stephan Kirchmayer

B&R
B&R
B&R

1.2.0
1.2.1

2019-04-08
2023-05-23

Stephan Kirchmayer
Stephan Kirchmayer

B&R
B&R

short description
createdANlocal, Anglobal flags added
1F98h si0 value range corrected
Minor layout changes, status changed to DSP
Minor layout changes, bit offset change in 1F82h,
D_NMT_DNA_BOOL added
Status changed to DS
Changes from TWG meeting 6/14 and 12/15
Status change to DSPStatus change to DS
Proposed changes
Changes from TWG meeting 10/18
Status change to DSPStatus change to DS© B&R due to dissolution onf the EPSGEPSG DS 302-E V1.2.1

Pre. 3Pre. 1Pre. 1.1
Pre. 2Pre. 3Pre. 4Pre. 5Pre. 6Pre. 6.1
Pre. 6.2
Pre. 7
1
2
2.1
2.2
2.3
2.4
2.5
2.6
3
3.1
3.2
4
5
5.1
5.2
5.3
6
6.1.1
6.1.2
6.1.3
6.1.4
6.1.5
6.1.6
7

-5-

Content
Disclaimer
Patent noticeHistory
Content
TablesFiguresDefinitions and Abbreviations
Definitions
Abbreviations
References
Introduction
BasicsGeneralTopology
Head-of-line node
Loss of communication, lease time
Compatibility
Features
Extensions of the communication profile specification
AN flags inside the SoC and SoA frames
NMT Command DNA
Controlled Node operation
Managing Node operation
GeneralLoss of a node
Ring redundancy
Additional Object Description
Object 1030h .. 1039 h: NMT_InterfaceGroup_Xh_REC
Object 1F81h: NMT_NodeAssignment_AU32
Object 1F82h: NMT_FeatureFlags_U32
Object 1F98h: NMT_CycleTiming_REC
Object 1FA0h: NMT_PredecessorNodeNumberList_AU32
Object 1FA1h: NMT_PredecessorHubPortList_AU32
Additional Device Description Entry (normative)

3
3
4
5
6
7
8
8
8
9
10
11
11
11
11
12
12
12
13
13
14
17
18
18
18
18
19
19
19
20
20
21
21
23

EPSG DS 302-E V1.2.1

Pre. 4
Tab. 1
Tab. 2
Tab. 3
Tab. 4
Tab. 5
Tab. 6
Tab. 7-6-

Tables
SoC frame structure
SoA frame structure
Additional SoC and SoA frame data fields
NMT Command DNA
NMT Command DNA data fields
NMT_NodeAssignment_AU32 additional bit interpretation
NMT_FeatureFlags_U32 additional bit interpretation

13
14
14
15
16
20
20

EPSG DS 302-E V1.2.1

Pre. 5
Fig. 1.
Fig. 2.
Fig. 3.

-7-

FiguresLine topology
Star topology with internal hub
Star topology with external hub

11
11
11

EPSG DS 302-E V1.2.1-8-Pre. 6

Definitions and Abbreviations

Pre. 6.1

Definitions

Pre. 6.2

Abbreviations

ASnd

Asynchronous Send (POWERLINK frame type)

CN

Controlled Node

CRC

Cyclic Redundancy CheckDNA

Dynamic Node Allocation

ID

Indentifier

MAC

Media Access Control

MN

Managing Node

NN

Node Number

PReq

Poll Request (POWERLINK frame type)

PRes

Poll Response (POWERLINK frame type)

PResMN

PRes frame of the Managing Node

SoA

Start of Asynchronous (POWERLINK frame type)

SoC

Start of Cyclic (POWERLINK frame type)EPSG DS 302-E V1.2.1

Pre. 7-9-

References[1]
EPSG Draft Standard 301 (EPSG DS 301), Ethernet POWERLINK, Communication Profile
Specification[2]
EPSG Draft Standard 302-A (EPSG 302-A), Ethernet POWERLINK, High Availability Extension

EPSG DS 302-E V1.2.1

1

-10-

Introduction

Setting the node number of POWERLINK devices turned out to be a significant source of error duringcommissioning. The node switches are tiny and often hard to recognize on the devices mounted in theelectrical cabinet.
If a wrong node number is assigned to a device the managing node is not able to identify it. Even worse,
if the same node number is set on two ore more devices usually all of them cannot be identified andadditionally collisions will occure on the network.
To overcome these troubles it would be much easier if there is no need to set any node number switch.
The node number should be assigned to the devices by the managing node instead.
This specification defines how to assign node numbers by the managing node depending on the
topology of the network.

EPSG DS 302-E V1.2.1

2

Basics2.1

General-11-

The node switch of all nodes that obtain their node number by DNA shall be set to 0.
The MN sends IdentRequest frames to the NN 0 to identify such nodes. When a node replies with an
IdentResponse the MN sends the NMT Command DNA to assign the node number.
To prevent all nodes with node switch 0 to reply to such an IdentRequest every node shall deactivate
sending on all its Ethernet ports in case node switch is 0 or the MN has set the AN flags inside the SoC
and SoA frames. Due to this the IdentRequest frame will only reach one node with no node number
configured. After assigning a node number the MN enables an Ethernet port of this node and sends
further IdentRequests.
The MN knows the network topology and with the NMT Command DNA it is able to switch on or off the
Ethernet ports of the CNs. So the MN is able to parse through the network, search for the nodes andassign the node numbers one by one.

2.2

Topology

DNA does not limit the topology of the network. However it might not be possible that every node gets
its node number from DNA service.
A line topolology can be built with DNA nodes easily. Therefore DNA capable nodes shall be equippedwith an onboard hub. This hub shall be able to switch on and off each hub port individually.
MN – 1 – 2 – 3 – 4
Fig. 1.

Line topology

A star topology may be implemented with nodes including a multi-port onboard hub. Each port of thishub shall be controllable by the node itself resp. by NMT command from the MN.
+–5–6–7|
MN – 1 – 2 – 3 – 4|+ – 8 – 9 – 10
Fig. 2.

Star topology with internal hub

Otherwise conventional hubs may be used. In this case DNA is not possible for the nodes connected tothe hub directly. These nodes are so called head-of-line nodes (marked with a * in the figure below). For
the nodes behind head-of-line nodes DNA is possible again.
+ – 1* – 2 – 3 – 4|
MN – Hub – 5* – 6 – 7|+ – 8* – 9 – 10
Fig. 3.

Star topology with external hub

Nodes not supporting DNA shall be placed at the end of a line or in separate segments. There is noneed to switch on or off ports of an hub. Anyway it is not allowed to place DNA devices behind devices
not supporting DNA.

2.3

Head-of-line node

The node number of a head-of-line node is derived from the node switch only and cannot not be
configured by NMT Command DNA.

EPSG DS 302-E V1.2.1-12-

A head-of-line node usually is the first node of a line of nodes. However every node with node switch
not equal 0 is called a head-of-line node.
Head-of-line nodes are used when connecting more than one node to an external hub. Because the hub
cannot be addressed with the NMT Command DNA for switching on and off its ports an IdentRequest
to NN0 will be received by all nodes directly connected to the hub. So all of them would reply to the
IdentRequest at the same time. This leads to a collision of the various IdentResponse frames.

2.4

Loss of communication, lease time

The node number set by the MN is only valid as long any POWERLINK communication takes place.
After the reception of the last POWERLINK frame the node number is still valid for the lease time. Whenthe lease time expires the node number is the number set by the node switch again.
The lease time is set by MN within the NMT Command DNA.
If no lease time is configured the new node number is valid until power down. In this case the node will
not respond to IdentRequests to NN0 until a power cycle is executed.

2.5

Compatibility

Conventional POWERLINK devices may be used in DNA networks without any restriction except
network topology.
Because it is not possible to switch on and off the Ethernet ports of conventional devices they shallalways be placed at the end of a line or in separate network segments. Anyway it is not allowed to place
DNA devices behind conventional devices.
For DNA configuration conventional devices are treated like head-of-line nodes.

2.6

Features•

No setting of the node number by node switch on the devices necessary•

Knowledge about the network topology necessary•

Increased network boot-up time (due to assigning the node number one by one)•Use of conventional devices and DNA devices in the same network possible•

DNA Nodes require a special onboard hub.

EPSG DS 302-E V1.2.1

-13-

3

Extensions of the communication profile
specification

3.1

AN flags inside the SoC and SoA frames

The MN sets the ANglobal flag in all SoC and SoA frames to indicate that DNA is active.
As a result CNs with an integrated hub shall not forward frames and send response frames on thereceive port only unless they receive a dedicated IdentRequest with the ANlocal flag reset or a specific
hub port has been activated by the NMT Command DNA.
Note:
The ANlocal flag is necessary in case a CN not supporting DNA is replaced by a CN supporting DNA
and the configuration on the MN has not been changed.
Otherwise the new CN supporting DNA would keep all its ports switched off because it interprets the
ANglobal flag and does not get a NMT Command DNA to switch on its ports.

Octet Offset 1

7

0
1
2
3
4

res

5
6 .. 13
14 .. 21
22

6

MC

PS

res

res

res

res

23 .. 25
26 .. 45
Tab. 1

5

4

Bit Offset
3

2

1

MessageType
Destination
Sourcereserved
res
res
AN
res
res
globalres
res
NetTime / reserved
RelativeTime / reserved
SoCFeatureFlags
res
res
res
res
res
SoCFeatureFlags (reserved)
reserved

0

res

DNA

SoC frame structure

1 Octet Offset refers to the start of the POWERLINK frame. Offset to the start of the Ethernet frame is

14 Octets.

EPSG DS 302-E V1.2.1

Octet Offset 2
0
1
2
3
4
5
6
7
8
9 .. 45
Tab. 2

-14-

7
res

6

res
res

res
res

Bit Offset
4
3
2
MessageType
Destination
SourceNMTStatus
AN
AN
res
local
global EA/res
res
RequestedServiceID
RequestedServiceTarget
EPLVersion
Reserved
5

1

0

ER/resres

res

SoA frame structure

Field
Abbr
Automatic Node AN
Numbering
globalglobal flag
Automatic Node AN
Numbering
local
specific flag
DNA feature flag DNA
in SoC

Tab. 3

Description
Value
Flag: Shall be set if DNA is active. On detection of this flag a CN
shall not forward frames and send response frames on thereceive port only unless a specific hub port has been activatedby a separate command.
Flag in IdentRequest only: Shall be set if DNA is active for a
dedicated CN. On detection of this flag reset a CN shall forward
frames and send response frames on all port, i.e. the CNs
behaves like a node not supporting DNA.
Flag: Shall be set if the MN is supporting DNA (and especiallysignalling of AN global flag in SoC).

Additional SoC and SoA frame data fields

See [1] for a detailed description of the SoC and SoA frame structure.

NMT Command DNA

3.2

This new NMT command shall be used to•

set the node number,•enable and disable ports of the onboard hub of CNs and• set the lease time of the node number.
Furthermore the MAC ID and current node number may be used additionally to make sure that the rightnode is addressed.

2 Octet Offset refers to the start of the POWERLINK frame. Offset to the start of the Ethernet frame is

14 Octets.

EPSG DS 302-E V1.2.1-15-

Bit Offset
Octet
Offset
03
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Tab. 4

7

6

5

res

res

res

res

4

3

2

1

MessageType
Destination
SourceService ID = 4
NMT Command ID = 0x2D (DNA)
LTV
HPM
NNN
MAC

0

CNN

Current MAC ID (48 Bit)

Hub-Port-Enable-Mask (64 Bit)

Current Node Number (32 Bit)

New NodeNumber (32 Bit)

Lease Time [µsec] (32 Bit)

NMT Command DNA

3 Octet Offset refers to the start of the POWERLINK frame. Offset to the start of the Ethernet frame is

14 Octets.

EPSG DS 302-E V1.2.1

-16-

Field
Lease time valid

Abbr Description
Value
LTV Flag: Shall be set if the field “Lease Time” is valid. The lease time shall be
adopted immediately.
Hub port enable HPM Flag: Shall be set if the field “Hub port enable mask” is valid. The dedicatedmask valid
hub ports shall be enabled immediately.
Set new node NNN Flag: Shall be set if the field “New node number” is valid. The new node
numbershallbeadoptedwithinthetimespecifiedinnumber
D_NMT_CNSetNodeNumberTime_U32.
Compare current MAC Flag: If set the CN shall compare the field “Current MAC ID” with its own
MAC ID
MAC ID before processing this NMT command.
Compare current CNN Flag: If set the CN shall compare the field “current node number” with its own
node number
node number before processing this NMT command.
Current MAC ID
Hub port enablemask

Current MAC ID of the CN addressed by this command.
Enable mask for the Ethernet ports of the onboard hub.

Current
node
numberNew
nodenumberLease Time

Current node number of the CN addressed by this command.

Tab. 5

New node number to be set.
Specifies how long the new node number set by this command is valid after
a Loss of communication occured. [µs]

NMT Command DNA data fields

Bit
value
0…disable
1…enableEPSG DS 302-E V1.2.1-17-

Controlled Node operation

4

If the node switch is set to 0 the node number is assigned to the CN by the NMT Command DNA. Aftera Loss of communication the new node number is valid until the lease time expires. Then the node
number is 0 again.
As long as no node number has been assigned the CN shall reply to an IdentRequest with
RequestedServiceTarget = 0.
On CNs with more than one Ethernet port, sending on these ports shall be deactivated by default if thenode switch is 0 or the CN receives an SoA with the ANglobal flag equal to 1.
The CN may only send response frames (Ident, Status, PReq) on a deactivated port if a request frame
has exactly been received on this port. No other frames may be sent on deactived ports.
A port is activated only if•

the device is in Basic Ethernet Mode or•

the CN receives a dedicated IdentRequest with the ANlocal flag reset or• the CN receives the dedicated NMT command.
If the AN flags inside the SoC and SoA frames are reset DNA is not used in the network then. Hence all
ports are active and act as usual.

Whatever topology is used one port of the CN is always connected towards the MN. The cable towards
the MN shall be connected to port no. 1. All other ports of the CN shall be used to connect further partsof the network.
In case of ring redundancy [2] port no. 2 shall be used as second port if the device has more than two
ports.

EPSG DS 302-E V1.2.1

-18-

5

Managing Node operation

5.1

GeneralSo far and without DNA the POWERLINK protocol is independent of the network topology. The MN does
not have any knowledge about the topology. The MN only knows about some timeouts due to runtimes
on the wire.
Now with DNA the MN must know the topology of the network to be able to parse through and search
for the CNs. This can be achieved with three parameters per node. These parameters are:•Predecessor node number
see Object 1FA0h: NMT_PredecessorNodeNumberList_AU32•

Hub port on predecessor.
See the chapter on Controlled Node operation for a detailed use of the different ports and Object
1FA1h: NMT_PredecessorHubPortList_AU32.

•

Head-of-line node yes/nosee Object 1F81h: NMT_NodeAssignment_AU32

The MN identifies the DNA nodes one by one. Therefore it has to switch on the dedicated hub port ofthe predecessor node and send an IdentRequest to NN0. If the node does not reply with an
IdentResponse the hub port of the predecessor has to be switched off. Now the MN is ready to search
for the next DNA node in another branch of the topology tree. If the node replies with an IdentResponse
the MN sends the NMT Command DNA to assign the node number and set the lease time. If the DNA
node replies to an IdentRequest with the new node number in the IdentResponse the MN is ready tosearch for the next DNA node in this line or in another branch.
Head-of-line nodes are identified with an IdentRequest to the dedicated node number.

5.2

Loss of a node

If the managing node detects the loss of a node it shall switch off the dedicated hub port of thepredecessor node immediately.
This is to make sure only one device responds to the IdentRequest to NN0. After switching off the hub
port the managing node may continue the search for not identified nodes.

5.3

Ring redundancy

Ring redundancy as defined in [2] may be used together with DNA. However special attention must be
paid on switching on and off the hub ports.

EPSG DS 302-E V1.2.1

-19-

6

Additional Object Description

6.1.1

Object 1030h .. 1039 h:
NMT_InterfaceGroup_Xh_REC

The following objects are used to configure and retrieve parameters of the network interfaces (physicalor virtual) via SDO. Each interface has one entry. See [1] for more details.
Additional subindex 0A h used:
Index
Name
Data Type1030h .. 1039 h
NMT_InterfaceGroup_Xh_REC
NMT_InterfaceGroup_Xh_TYPE

Object TypeRECORD

Category

1030h:
M
1031h .. 1039h: O

To allow access by name “_Xh” is replaced with a name index. For example, the name index is“_0h” if the object index is 1030h. The name index is incremented up to “_9h” corresponding to
object index 1039h.
•

Sub-Index 00h: NumberOfEntries
Sub-Index
Name
Value Range
Default Value

00h
NumberOfEntries
9-10-

AccessPDO Mapping

const
No

Category
AccessPDO Mapping

O
ro
No

NumberOfEntries is implemetation specific.
•

Sub-Index 0Ah: PortEnableMask_U64
Sub-Index
Name
Data Type
Value Range
Default Value

0Ah
PortEnableMask_U64
UNSIGNED64
UNSIGNED64-

This value is set by the field Hub-Port-Enable-Mask of the NMT Command DNA frame and may
be read for diagnosis.
PortEnableMask_U64 specifies the enable mask for all ports of this interface, e.g. in case of an
Ethernet interface with an onboard hub is used.
Value interpretation: Every bit corresponds to a port. Bit enumeration starts with the LSB. Bit value= 0…port disabled, = 1…port enabled.

6.1.2

Object 1F81h: NMT_NodeAssignment_AU32

This object assigns nodes to the NMT Master (MN). On the CN the object is conditional. See [1] formore details.
Each sub-index in the array corresponds to the node with the node ID equal to the sub-index.
The object should be set by the system configuration.
Additional bit used:EPSG DS 302-E V1.2.1

Index
Name
Data Type
•

-20-

1F81h
NMT_NodeAssignment_AU32
UNSIGNED32

Object Code

ARRAY

Category

MN: M
CN: Cond

Category
AccessPDO MappingM
rw, valid on resetNo

Sub-Index 01h .. FEh: NodeAssignment
Sub-Index
Name-Value Range
Default Value

Octet
2

Bit
15

Value
0b
1b

Tab. 66.1.3

01h .. FEh
NodeAssignment-Bit field, see below
0

Description
Nodenumbernotassigned(head-of-line node)
Node number assigned by DNA

Property Evaluate
DNA CNMN

by

NMT_NodeAssignment_AU32 additional bit interpretation

Object 1F82h: NMT_FeatureFlags_U32

The Feature Flags indicate communication profile specific properties of the device given by its design.
The object shall be setup by the device firmware during system initialisation.
Additional bit used:
Octet Bit
2
20

Tab. 7

6.1.4

Name
Dynamic Node Allocation

TRUE
Device supports DNA

FALSE
Device does not support DNA

NMT_FeatureFlags_U32 additional bit interpretation

Object 1F98h: NMT_CycleTiming_REC

NMT_CycleTiming_REC provides node specific timing parameters, that influence the POWERLINK
cycle timing.
Additional subindex 0Fh used on the CN only:EPSG DS 302-E V1.2.1

Index
Name
Data Type•

1F98h
NMT_CycleTiming_REC
NMT_CycleTiming_TYPE

Object CodeRECORD

CategoryM

AccessPDO Mapping

const
No

Category
AccessPDO Mapping

MN: no, CN: O
roNo

Sub-Index 00h: NumberOfEntries
Sub-Index
Name
Value Range
Default Value

•

-21-

00h
NumberOfEntries
9 .. 15-

Sub-Index 0Fh: LeaseTime_U32
Sub-Index
Name
Data Type
Value Range
Default Value

0Fh
LeaseTime_U32
UNSIGNED32
UNSIGNED32
0This value [µs] is set by the field Lease Time of the NMT Command DNA frame and may be readfor diagnosis.
LeaseTime_U32 specifies how long the new node number set by NMT Command DNA is valid
after a Loss of communication occurred.

6.1.5

Object 1FA0h:
NMT_PredecessorNodeNumberList_AU32

NMT_PredecessorNodeNumberList_AU32 holds a list of the predecessor node number of the nodes.
Index
Name
Data Type•ARRAY
MN: M, CN: no

Sub-Index 0h: NumberOfEntries
Sub-Index
Name
Value Range
Default Value

•

1FA0h
Object Code
NMT_ PredecessorNodeNumberList_AU32
UNSIGNED32
Category

00h
NumberOfEntries
1 .. 254
254

AccessPDO Mappingrw
No

Category
AccessPDO Mapping

M
rw
No

Sub-Index 01h .. FEh: PredecessorNodeNumber
Sub-Index
Name-Value Range
Default Value

01h .. FEh
PredecessorNodeNumber-UNSIGNED32
240

Each sub-index in the array corresponds to the CN with the Node ID equal to the sub-index. The
sub-index value is valid only if there is a CN assigned to the Node ID by index
NMT_NodeAssignment_AU32[sub-index] bits 0 and 1.
Each sub-index holds the node number of the predecessor node.

6.1.6

Object 1FA1h:
NMT_PredecessorHubPortList_AU32

NMT_PredecessorHubPortList_AU32 holds a list of the hub port number on the predecessor node.

EPSG DS 302-E V1.2.1

Index
Name
Data Type•

1FA1h
Object Code
NMT_ PredecessorHubPortList_AU32
UNSIGNED32
Category

ARRAY
MN: M, CN: no

Sub-Index 0h: NumberOfEntries
Sub-Index
Name
Value Range
Default Value

•

-22-

00h
NumberOfEntries
1 .. 254
254

AccessPDO Mappingrw
No

Category
AccessPDO Mapping

M
rw
No

Sub-Index 01h .. FEh: PredecessorHubPort
Sub-Index
Name-Value Range
Default Value

01h .. FEh
PredecessorHubPort-UNSIGNED32
0Each sub-index in the array corresponds to the CN with the Node ID equal to the sub-index. The
sub-index value is valid only if there is a CN assigned to the Node ID by index
NMT_NodeAssignment_AU32[sub-index] bits 0 and 1.
Each sub-index holds the hub port number on the predecessor node.
The value 0 indicates that it is not possible to switch the hub port of the predecessor node on or
off.

EPSG DS 302-E V1.2.1

7

-23-

Additional Device Description Entry (normative)

Name

Description

Type

D_NMT_CNDNA_BOOL
D_NMT_CNSetNodeNumberTime_U32

Ability of a Controlled Node to perform Dynmic Node Allocation
Maximum time the CN needs to set the new node number in[µs]
Ability of a Managing Node to perform Dynmic Node Allocation

D_NMT_MNDNA_BOOL

end-of-file

BOOL
UNSIGNED32

Category
MN
CN
M
M

MN
-

CN
N
0

BOOL

M

N

-

-

Default