Rockwell Automation Allen-Bradley ControlLogix DeviceNet... User manual

ControlLogix
DeviceNet
Interface Module
1756-DNB
User Manual

Important User Information
Because of the variety of uses for the products described in this
publication, those responsible for the application and use of this
control equipment must satisfy themselves that all necessary steps
have been taken to assure that each application and use meets all
performance and safety requirements, including any applicable laws,
regulations, codes and standards.
The illustrations, charts, sample programs and layout examples shown
in this guide are intended solely for purposes of example. Since there
are many variables and requirements associated with any particular
installation, Allen-Bradley does not assume responsibility or liability
(to include intellectual property liability) for actual use based upon
the examples shown in this publication.
Allen-Bradley publication SGI-1.1, Safety Guidelines for the
Application, Installation and Maintenance of Solid-State Control
(available from your local Allen-Bradley office), describes some
important differences between solid-state equipment and
electromechanical devices that should be taken into consideration
when applying products such as those described in this publication.
Reproduction of the contents of this copyrighted publication, in whole
or part, without written permission of Rockwell Automation, is
prohibited.
Throughout this manual we use notes to make you aware of safety
considerations:
Attention statements help you to:
•identify a hazard
•avoid a hazard
•recognize the consequences
Allen-Bradley, ControlLogix, and Data Highway Plus are trademarks of Rockwell Automation.
ControlNet is a trademark of ControlNet International, Ltd.
DeviceNet is a trademark of Open DeviceNet Vendor Association, Inc.
Ethernet is a trademark of Digital Equipment Corporation, Intel, and Xerox Corporation.
RSLinx, RSLogix 5000, and RSNetWorx are trademarks of Rockwell Software.
Windows 95/98 and Windows NT are trademarks of Microsoft Corporation.
ATTENTION
!
Identifies information about practices or
circumstances that can lead to personal injury or
death, property damage or economic loss.
IMPORTANT Identifies information that is critical for successful
application and understanding of the product.

European Communities (EC)
Directive Compliance
If this product has the CE mark it is approved for installation within
the European Union and EEA regions. It has been designed and tested
to meet the following directives.
EMC Directive
This product is tested to meet the Council Directive 89/336/EC
Electromagnetic Compatibility (EMC) by applying the following
standards, in whole or in part, documented in a technical construction
file:
•EN 50081-2 EMC — Generic Emission Standard, Part 2 —
Industrial Environment
•EN 50082-2 EMC — Generic Immunity Standard, Part 2 —
Industrial Environment
This product is intended for use in an industrial environment.
Low Voltage Directive
This product is tested to meet Council Directive 73/23/EEC Low
Voltage, by applying the safety requirements of EN 61131-2
Programmable Controllers, Part 2 - Equipment Requirements and
Tests. For specific information required by EN 61131-2, see the
appropriate sections in this publication, as well as the Allen-Bradley
publication Industrial Automation Wiring and Grounding Guidelines
For Noise Immunity, publication 1770-4.1.
This equipment is classified as open equipment and must be mounted
in an enclosure during operation to provide safety protection.

1Publication 1756-6.5.19 - May 2000
Preface
About This User Manual
Introduction
This user manual is designed to provide you enough information to
get a small example application up and running. Use this manual if
you are knowledgeable about DeviceNetand ControlLogix
products, but may not have used the products in conjunction. The
information provided is a base; modify or expand the examples to suit
your particular needs.
The manual contains instructions on configuring a DeviceNet network
using RSLinx and RSNetWorx for DeviceNet software over various
networks:
•directly over the DeviceNet network
•from a ControlNet network
•from an Ethernet network
•from a Data Highway Plus network
The example application demonstrates how to perform control on a
DeviceNet network using a Logix5550 controller and the 1756-DNB
module. You use RSLogix 5000 programming software to create a
ladder logic program to control a photoeye and a RediSTATION.
IMPORTANT This User Manual should be used in conjunction with
the 1756-DNB DeviceNet Scanner Module
Installation Instructions, publication 1756-5.66. The
Installation Instructions contain important
information on configuring your scanner.

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P-2 About This User Manual
Contents
This user manual contains the following chapters:
Audience
This manual is intended for control engineers and technicians who are
installing, programming, and maintaining a control system that
includes a Logix5550 controller communicating on a DeviceNet
network through a 1756-DNB module.
We assume that you:
•are developing a DeviceNet network using a ControlLogix
chassis in conjunction with a 1756–DNB interface module
•know each of your device’s I/O parameters and requirements
•are experienced with the Microsoft®Windowsenvironment
•are familiar with RSNetWorx for DeviceNet software
2
1
3
Planning Your
Configuration
go to Chapter 2
4Configuring the
DeviceNet Network
go to Chapter 4
Configuring DeviceNet
From Another Network
go to Chapter 5
5
Before You Begin
go to Chapter 1
Setting Up the
Hardware
go to Chapter 3
Creating and Running
the Application Program
go to Chapter 6
6
7Troubleshooting
go to Chapter 7

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About This User Manual P-3
The Example Application
This manual describes how to set up an example application. The
manual provides examples of each step of the setup, with references
to other manuals for more details.
System Components
We used the following devices and software for the example
application. For your own application, substitute your own devices to
fit your needs. The recommended configurations in this user manual
will help you set up the test system and get it working. Your eventual
configuration will depend on your application.
Note: If you use different software or fimware versions of these
products some of your screens may appear slightly different from
those shown in the example.
Product Name Catalog Number Series Revision
Qty Hardware
1 ControlLogix chassis 1756-A4, -A7, -A10 - -
1 Logix5550 controller 1756-L1 A 5.12
1 ControlLogix DeviceNet Interface module 1756-DNB A 3.003
1 DeviceNet Quad-Tap 1492-DN3TW - -
1 RediSTATION operator interface module 2705-T3DN1A42A - -
1 Series 9000 Photoeye 42GNP-9000 or equivalent - -
1 DeviceNet PC serial communication module 1770-KFD A 1.04
1 RS-232 cable 1787-RSCABL/A (PC to 1770-KFD) - -
1 24V Power Supply Regulated 24VDC, 8A - -
1 PC IBM-compatible
Windows NT 4.0
--
DeviceNet dropline or trunkline
cables, as needed
1787-PCABL, -TCABL, -MCABL - -
1(1) ControlLogix ControlNet Interface module 1756-CNB B 2.24
1(2) ControlLogix Data Highway Plus Interface
module
1756-DHRIO B 2.17
1(3) ControlLogix Ethernet Interface module 1756-ENET A 1.18
Software
RSLogix 5000 9324-RL5300END - 2.51
RSNetWorx for DeviceNet 9357-DNETL3, - 2.11
RSLinx 9355-WAB - 2.10
(1) Required if interfacing the DeviceNet network and a ControlNet network. See chapters 5 and 6.
(2) Required if interfacing the DeviceNet network and a Data Highway Plus network. See chapters 5 and 6.
(3) Required if interfacing the DeviceNet network and an Ethernet network. See chapters 5 and 6.

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P-4 About This User Manual
Common Techniques
Used in This Manual
The following conventions are used throughout this manual:
•Bulleted lists provide information, not procedural steps.
•Numbered lists provide sequential steps.
•Information in bold contained within text identifies menu
windows, or screen options, screen names and areas of the
screen, such as dialog boxes, status bars, radio buttons and
parameters.
TIP This symbol identifies helpful tips.
A definition box defines terms that may be unfamiliar to you.
Screen captures are pictures of the software’s actual screens. The
names of screen buttons and fields are often in bold in the text of
a procedure. Pictures of keys represent the actual keys you press.
The “MORE” icon is placed beside any paragraph that references
sources of additional information outside of this document.
This is a definition
box. When a word is
bold within the text
of a paragraph, a
definition box will
appear in the left
margin to further
define the text.
More

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About This User Manual P-5
Where to Find
More Information
Refer to the following publications as needed for additional help
when setting up and using your DeviceNet network:
More
For information about See this publication Publication Number
the ControlLogix DeviceNet interface module ControlLogix DeviceNet Scanner Module Installation Instructions 1756-5.66
the ControlLogix Chassis ControlLogix Chassis Installation Instructions 1756-5.2
ControlLogix power supplies ControlLogix Power Supplies Installation Instructions 1756-5.1
connecting the DeviceNet network DeviceNet Cable Planning and Installation Manual DN-6.7.2
the 1770-KFD communication module DeviceNet RS-232 Interface Module Installation Instructions 1770-5.6
the Logix5550 controller Logix5550 Controller User Manual 1756-6.5.12
the RediSTATION RediSTATION Operator Interface User Manual 2705-804
the ControlLogix ControlNet Interface module ControlLogix ControlNet Bridge Installation Instructions 1756-5.32
the ControlLogix DH+ Interface module ControlLogix DHRIO Module Installation Instructions 1756-5.4
the ControlLogix Ethernet Interface module ControlLogix Ethernet Module Installation Instructions 1756-5.3
RSLogix 5000 software Getting Results with RSLogix 5000 9399-RLD300GR
RSLinx software RSLinx Lite User Guide 9399-WAB32LUG
RSNetWorx for DeviceNet software See the software’s online Help N/A
terms and definitions Allen-Bradley Industrial Automation Glossary AG-7.1
TIP Many of the above publications are available
online from the Automation Bookstore:
http://www.theautomationbookstore.com.
TIP For more information about Rockwell Software
products, visit the Rockwell Software internet site:
http://www.software.rockwell.com.

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P-6 About This User Manual
Terminology
This term Means
Bridge The interface module’s support of explicit message transfer.
Change of State A type of I/O data communication. The interface module can send and
receive data with slave devices that have the change of state feature. Data
is sent whenever a data change occurs. Data is updated at the rate of the
heartbeat.
Communication
Module
The 1756-DNB interface module or the 1770-KFD module.
Cyclic A type of I/O data communication. The interface module can send and
receive data with slave devices that have the cyclic feature. Data is only
sent at a user-configurable rate.
EDS Electronic Data Sheet. A vendor-supplied template that specifies how
information is displayed as well as what is an appropriate entry (value).
Explicit
Messaging
A type of messaging used for lower priority tasks, such as configuration
and data monitoring.
Heartbeat Rate Devices that are configured for change of state data can also send a
“heartbeat” signal to indicate proper operation.
Host Platform The computer that hosts the 1756-DNB interface module.
I/O An abbreviation for “input and output”.
Implicit
Messaging
The type of messaging used for high priority I/O control data; e.g., change
of state, cyclic, polled, or strobed.
Input Data Data produced by a DeviceNet device and collected by the interface
module for a host platform to read.
MAC ID The network address of a DeviceNet node.
Network The DeviceNet network or the RSNetWorx for DeviceNet software
representation of the network.
Node Hardware that is assigned a single address on the network (also referred
to as device).
Offline When the PC communication interface is not communicating on the
network.
Online When the PC communication interface is configured and enabled to
communicate on the network.
Output Data Data produced by a host platform that is written to the interface module’s
memory. This data is sent by the interface module to DeviceNet devices.
PC Abbreviation for an IBM®compatible personal-computer.
Polled A type of input/output-data communication. A polled message solicits a
response from a single, specified device on the network (a point-to-point
transfer of data).
Record The node address and channel-specific memory assigned in the interface
module’s non-volatile storage for a node in the scanlist.
Rx An abbreviation for “receive”.
Scanlist The list of devices (nodes) with which the scanner is configured to
exchange I/O data.
Scanner The function of the 1756-DNB interface module to support the exchange of
I/O with slave modules.
Slave Mode The interface module is in slave mode when it is placed in another
interface module’s scanlist as a slave device.
Strobed A type of I/O data communication. A strobed message solicits a response
from each strobed device (a multicast transfer). It is a 64-bit message that
contains one bit for each device on the network.
Tx An abbreviation for “transmit”.

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About This User Manual P-7
Rockwell Automation
Support
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sales/support offices, 512 authorized distributors, and 260 authorized
systems integrators located throughout the United States alone, plus
Rockwell Automation representatives in every major country in the
world.
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Contact your local Rockwell Automation representative for:
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If you need to contact Rockwell Automation for technical assistance,
call your local Rockwell Automation representative, or call Rockwell
directly at: 1 440 646-6800.
For presales support, call 1 440 646-3NET.
You can obtain technical assistance online from the following
Rockwell Automation WEB sites:
•www.ab.com/mem/technotes/kbhome.html (knowledge base)
•www.ab.com/networks/eds (electronic data sheets)
Your Questions or Comments about This Manual
If you find a problem with this manual, please notify us of it on the
enclosed Publication Problem Report (at the back of this manual).
If you have any suggestions about how we can make this manual
more useful to you, please contact us at the following address:
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Control and Information Group
Technical Communication
1 Allen-Bradley Drive
Mayfield Heights, OH 44124-6118

Publication 1756-6.5.19 - May 2000
P-8 About This User Manual

iPublication 1756-6.5.19 - May 2000
Table of Contents
Chapter 1
Before You Begin
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 1-1
What You Need to Know . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
What Your 1756-DNB Module Does. . . . . . . . . . . . . . . . . . 1-2
Communicating with Your Devices . . . . . . . . . . . . . . . . . . 1-4
What 1756-DNB Module Data Tables Are
and What They Do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
The Scanner Configuration Table (SCT) . . . . . . . . . . . . 1-5
The Scanlist Table (SLT). . . . . . . . . . . . . . . . . . . . . . . . 1-6
RSNetWorx Software as a Configuration Tool . . . . . . . . . . . 1-6
RSNetWorx for DeviceNet Configuration Screen Map. . . 1-7
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Chapter 2
Planning Your Configuration and
Data Mapping Your Devices
What You Need to Know . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Beginning the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
The Example Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
Example Network Devices . . . . . . . . . . . . . . . . . . . . . . 2-2
RediSTATION Operator Interface Data Mapping . . . . . . 2-4
RediSTATION Input Data Mapping Example . . . . . . . . . 2-5
RediSTATION Output Data Mapping Example. . . . . . . . 2-6
Photoeye Input Data Mapping . . . . . . . . . . . . . . . . . . . 2-7
Photoeye Input Data Mapping Example . . . . . . . . . . . . 2-8
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Chapter 3
Hardware Setup
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 3-1
Installing the 1770-KFD Communication Module . . . . . . . . 3-1
Installing the Logix5550 Controller. . . . . . . . . . . . . . . . . . . 3-2
Installing the 1756-DNB Interface Module . . . . . . . . . . . . . 3-2
Installing a ControlNet, Ethernet, or DH+ Interface Module. 3-3
Installing the RediSTATION Operator Interface. . . . . . . . . . 3-5
Installing the Series 9000 Photoeye . . . . . . . . . . . . . . . . . . 3-6
How Your Example System Will Look . . . . . . . . . . . . . . . . 3-7
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Chapter 4
Configuring the
DeviceNet Network
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 4-1
Installing the Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Using RSLinx to Configure the DeviceNet Driver . . . . . . . . 4-2
Using RSNetWorx to Configure
the 1756-DNB Module Scanlist. . . . . . . . . . . . . . . . . . . . . . 4-4
Setting Up an Online Connection . . . . . . . . . . . . . . . . . 4-4
Setting the 1756-DNB Node Address. . . . . . . . . . . . . . . 4-6
Configuring the Scanlist . . . . . . . . . . . . . . . . . . . . . . . . 4-9

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Table of Contents ii
Chapter 4 (continued)
Verifying the Photoeye Configuration . . . . . . . . . . . . . . . 4-12
Verifying the RediSTATION Configuration . . . . . . . . . . . 4-14
AutoMapping the Devices into the Scanlist . . . . . . . . . . . 4-15
Saving the DeviceNet Configuration . . . . . . . . . . . . . . . 4-18
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Chapter 5
Configuring DeviceNet
From Another Network
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 5-1
Where to Find More Information . . . . . . . . . . . . . . . . . . . . 5-2
Configuring DeviceNet from a ControlNet Network . . . . . . 5-2
Configuring DeviceNet from an Ethernet Network . . . . . . . 5-5
Configuring DeviceNet From a Data Highway Plus Network 5-8
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
Chapter 6
The Example
Application Program
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 6-1
Installing the Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Creating the Example Application . . . . . . . . . . . . . . . . . . . 6-2
Creating a New Controller . . . . . . . . . . . . . . . . . . . . . . 6-2
Creating the Controller Tags . . . . . . . . . . . . . . . . . . . . . 6-3
I/O Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Creating the Ladder Logic. . . . . . . . . . . . . . . . . . . . . . . 6-7
Downloading and Running the Example
Application Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Downloading and Running the Program
from a ControlNet Network . . . . . . . . . . . . . . . . . . . . . 6-9
Downloading and Running the Program
from an Ethernet Network . . . . . . . . . . . . . . . . . . . . . . 6-11
Downloading and Running the Program
from a DH+ Network . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Chapter 7
Troubleshooting
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . 7-1
Power-Up Cycle Diagnostics . . . . . . . . . . . . . . . . . . . . . . . 7-1
Node Address/Status Indicator. . . . . . . . . . . . . . . . . . . . . . 7-2
Interpreting the Three LED Status Indicators. . . . . . . . . . . . 7-4
MOD/NET Status Indicator . . . . . . . . . . . . . . . . . . . . . . 7-4
IO Status Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
OK Status Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Appendix A
1756-DNB Status Structure
Module Status Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Index

1Publication 1756-6.5.19 - May 2000
Chapter 1
Before You Begin
What This Chapter Contains
This chapter provides an overview of communication between a
Logix5550 controller and DeviceNet devices via a 1756-DNB module.
The data tables and the RSNetWorx for DeviceNet screens and
windows used to configure data tables are also described.
The following table identifies what this chapter contains and where to
find specific information.
What You Need to Know
Before configuring your 1756-DNB module, you must understand:
•the data exchange between the controller and DeviceNet
devices through the 1756-DNB module
•user-configurable 1756-DNB module data tables
•the role of RSNetWorx for DeviceNet software
For information about See page
What You Need to Know 1-1
What Your 1756-DNB Module Does 1-2
Communicating with Your Devices 1-4
What 1756-DNB Module Data Tables Are and What They Do 1-5
The Scanner Configuration Table (SCT) 1-5
The Scanlist Table (SLT) 1-6
RSNetWorx Software as a Configuration Tool 1-6
RSNetWorx for DeviceNet Configuration Screen Map 1-7

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1-2 Before You Begin
What Your 1756-DNB
Module Does
In a typical configuration, the 1756-DNB module acts as an interface
between DeviceNet devices and the Logix5550 controller.
The 1756-DNB module communicates with DeviceNet devices over
the network to:
•read inputs from a device
•write outputs to a device
•download configuration data
•monitor a device’s operational status
The 1756-DNB module communicates with the controller in the form
of Input, Output, and Diagnostic Tables. Information exchanged
includes:
•device I/O data
•status information
•configuration data
ControlLogix
1770-KFD
Interface
Module
PC with RSNetWorx
for DeviceNet software
Series 9000
Photoeye RediSTATION
1305 Drive
FLEX I/O Rack
DeviceNet
Devices
Chassis
Logix5550
Controller
1756-DNB
Module
DeviceNet Network

Publication 1756-6.5.19 - May 2000
Before You Begin 1-3
A controller to I/O DeviceNet configuration is shown in the following
figure. See the referenced chapters for information on a particular
topic.
The 1756-DNB interface module can also be used to bridge a
DeviceNet network with another network. See the referenced chapters
for information on a particular topic.
PC running
RSNetWorx
for DeviceNet
Configure DNB module (Chapter 4)
Mapping Table (Chapters 2 and 4)
Input
Device
Output
Device
Input Data from
Device to DNB
(Chapter 2)
DeviceNet Network
Output Data to Devices
from DNB (Chapter 2)
Controller to I/O
Input Read by Controller (Chapter 2)
Output Write by
Controller (Chapter 2)
Configuring Devices and Data Collection on
Higher-Level Networks Via ControlLogix/DNB
Target Device to
be configured
Source Device to
collect data
DeviceNet Network
Industrial workstation
running RSView Laptop PC running
RSNetWorx for DeviceNet
ControlNet, DH+, or Ethernet Network
1756-CNB, -DHRIO. or
-ENET interface module
Collection of status or
alarm data (Chapter 6)
Configuration of devices
using RSNetWorx (Chapters 4 & 5)
1756-DNB Module
Configuration of Devicenet Network
via ControlNet, DH+, or Ethernet
(Chapter 5)
Logix 5550 Processor

Publication 1756-6.5.19 - May 2000
1-4 Before You Begin
Communicating with
Your Devices
The 1756-DNB module communicates with a device via strobe, poll,
change of state,
and/or cyclic messages. It uses these messages to solicit
data from or deliver data to each device. Data received from the devices,
or input data, is organized by the 1756-DNB module and made available
to the controller. Data received from your Logix5550 controller, or output
data, is organized in the 1756-DNB module and sent on to your devices.
IMPORTANT
Throughout this document, input and output are defined
from the Logix5550 controller’s point of view. Output is
data sent from the Logix5550 controller
to a device. Input
is data collected by the Logix5550 controller
from a device.
All data sent and received on a DeviceNet network is in
byte lengths. A device may, for example, produce only two
bits of input information. Nevertheless, since the minimum
data size on a DeviceNet network is one byte, two bits of
information are included in the byte of data produced by
the device. In this example (only two bits of input
information), the upper six bits are insignificant.
A strobe message is a
multicast transfer of data
(which is 64 bits in length)
sent by the 1756-DNB
module that solicits a
response from each strobed
slave device. There is one bit
for each of the possible 64
node addresses. The devices
respond with their data,
which can be as much as 8
bytes.
A poll message is a
point-to-point transfer of
data (0-255 bytes) sent by
the 1756-DNB module that
solicits a response from a
single device. The device
responds with its input data
(0-255 bytes).
A change of state message
is a transfer of data sent
whenever a data change
occurs. A user-configurable
heartbeat rate can also be
set to allow devices to
indicate proper operation
during intervals between
data changes. This does not
solicit response data, but
may receive an acknowledge
message.
A cyclic message is sent only
at a user-configurable rate,
such as every 10 ms.
1756-DNB Module DeviceNet Devices
Input Data Storage
Input Data From
DeviceNet Devices
E
Y
X
Y
Y
Different portions of data from
a single device can be mapped
to separate 1756-DNB module
memory locations. For example,
“On/Off” values can be mapped
to one location, diagnostic
values to another, etc. This is
known as “map segmenting.”
This concept is illustrated by
byte A, stored separately as
segments A1 and A2.
Output Data Storage
Output Data To
DeviceNet Devices
Byte
,
0
1
2
3
4
5
6
Z
Y
Y
Y
output from
the Logix 5550
controller
B
A1
C
D
A2
E
E
input from the
devices to the
controller
B
C
D
X
Z
A1 A2

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Before You Begin 1-5
What 1756-DNB Module
Data Tables Are and What
They Do
To manage the flow of data between your controller and the network
devices, the 1756-DNB module uses the following data tables.
•1756-DNB Module Configuration Table
•Scanlist Table
•Device Input Data Table
•Device Output Data Table
•Device Idle Table
•Device Failure Table
You can configure two of these data tables through RSNetWorx
software. These two tables are stored in the 1756-DNB module’s
non-volatile memory and used to construct all other data tables:
•Scanner Configuration Table (SCT)
•Scanlist Table (SLT)
The Scanner Configuration Table (SCT)
The SCT controls basic information your 1756-DNB module needs to
function on your DeviceNet network. It tells your 1756-DNB module:
•if it can transmit and receive input and output data
•how long it waits after each scan before it scans the devices
again
•when to send out its poll messages

Publication 1756-6.5.19 - May 2000
1-6 Before You Begin
The Scanlist Table (SLT)
The SLT supports I/O updating for each of your devices on the
network. It also makes it possible for your 1756-DNB module to make
device data available to your controller. The SLT tells your 1756-DNB
module:
•which device node addresses to scan
•how to scan each device (strobe, poll, change of state, cyclic or
any valid combination)
•how often to scan your devices
•exactly where in each device’s total data to find the desired data
•the size of the input data/output data
•exactly where to map the input or output data for your
controller to read or write
RSNetWorx Software as a
Configuration Tool
RSNetWorx for DeviceNet software is used to configure the 1756-DNB
module’s data tables. This software tool connects to the 1756-DNB
module over the DeviceNet network via a 1770–KFD interface module
or PC Card (1784-PCID, -PCIDS, or -PCMCIA).
User-
configured
Tables
Data in this Table RSNetWorx Configuration
Screen
SCT • basic operation
• module parameters
• interscan delay
• background poll ratio
1756-DNB Module Configuration
SLT • device-specific
identification data
Scanlist Editor (SLE)
• data transfer method
• transmit/receive data size
Edit Device I/O Parameters
• input and output data
source and destination
locations
These values can be configured
automatically through the
AutoMap function or manually
through the Data Table Map.
Interscan delay is the time between
I/O scans (polled and strobed). It is
the time the 1756-DNB module will
wait between the last poll message
request and the start of the next scan
cycle.
Background poll ratio sets the
frequency of poll messages to a
device in relation to the number of
I/O scans. For example, if the ratio
is set at 10, that device will be
polled once every 10 scans.
TIP The 1756-DNB module can also be configured
remotely from a ControlNet, Ethernet, or Data
Highway Plus network. See chapter 5.