Allen-Bradley ControlLogix 1756-ENBT User manual

ControlLogix
Ethernet Bridge
Module
1756-ENBT
User Manual
AB Parts

Important User Information
Because of the variety of uses for the products described in this
publication, those responsible for the application and use of these
products 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. In no event will Allen-Bradley be responsible or
liable for indirect or consequential damage resulting from the use or
application of these products.
Any illustrations, charts, sample programs, and layout examples
shown in this publication 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 publication, notes may be used to make you aware of
safety considerations. The following annotations and their
accompanying statements help you to identify a potential hazard,
avoid a potential hazard, and recognize the consequences of a
potential hazard:
WARNING
!
Identifies information about practices or
circumstances that can cause an explosion in a
hazardous environment, which may lead to personal
injury or death, property damage, or economic loss.
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.

Rockwell Automation
Support
Before you contact Rockwell Automation for technical assistance, we
suggest you please review the troubleshooting information contained
in this publication first.
If the problem persists, call your local Rockwell Automation
representative or contact Rockwell Automation in one of the
following ways:
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1Publication 1756-UM050A-EN-P - December 2001
Preface
About This User Manual
What this Preface Contains
This preface describes how to use this manual. The following table
describes what this preface contains and where to find specific
information.
Who Should Use
This Manual
This manual is intended for control engineers and technicians who are
installing, programming, and maintaining a control system that
communicates on an EtherNet/IP network through a 1756-ENBT
Bridge.
We assume you have a good understanding of Ethernet and the
(TCP/IP) protocol. This user manual contains a brief description of
Ethernet and TCP/IP in Chapter 3.
For information about See page
Who Should Use This Manual P-1
Common Techniques Used in This Manual P-2
How To Use This Manual P-2
About the Example Applications P-3
System Components P-4
Where to Find More Information P-5
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P-2 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.
How To Use This Manual
This manual provides an overview of the 1756-ENBT module, as well
as general information about Ethernet. It describes how to install and
configure the module, and provides four example applications
showing how to use the module to communicate over EtherNet/IP.
The example applications are intended as building blocks to help you
get your own network up and running. We recommend that you set
up and run the example applications and use them as a guide for
setting up your own system.
TIP This symbol identifies helpful tips.
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.

Publication 1756-UM050A-EN-P - December 2001
About This User Manual P-3
About the Example Applications
The example applications presented in this manual are as follows:
•Using Rack Optimized I/O (chapter 5)
•Using Analog I/O with Direct Connection (chapter 6)
•Using Produced and Consumed tags (chapter 7)
•Communicating with FLEX I/O (chapter 8)
Here’s an example of the type of system you’ll be creating:
Data
Slot 0 1 Slot 0 1 2 3
Switch
Programming
130.130.130.1
Terminal
Local
Chassis Remote
Chassis
Logix5550
Controller 1756-ENBT
130.130.130.2 1756-ENBT
130.130.130.3
1756-IB16I
Digital Input
1756-OB16I
Digital Output
1756-OF8
Analog Output
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P-4 About This User Manual
System Components
We used the following components for the example applications:
Quantity Product Name Catalog Number
Hardware
2 ControlLogix Chassis 1756-A4, (or -A7, -A13, -A13, -A17)
2 ControlLogix Power Supply 1756-PA72, (or -PB72)
2 ControlLogix EtherNet/IP Bridge Module 1756-ENBT
2 Logix5550 Controller 1756-L1
1 ControlLogix Analog Output Module 1756-OF8
1 ControlLogix Digital Input Module 1756-IB16I
1 ControlLogix Digital Output Module 1756-0B16I
1 FLEX I/O EtherNet/IP Adapter 1794-AENT
1 FLEX I/O Digital Input Module 1794-IB16
1 FLEX I/O Digital Output Module 1794-OB16
1 Personal computer that supports RSLogix
5000 software Any appropriate model running Windows NT 4.0, Service Pack 5 or
higher
1 Ethernet switch Refer to manufacturer’s
specifications
Associated media and connectorsas needed
Software
1 RSLinx V2.30 9355-WAB, -WABOEM, -WABC
1 RSLogix 5000 programming software V8.1 9324-RLD300ENE

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About This User Manual P-5
Where to Find More
Information Refer to the following Rockwell publications as needed for additional
help when setting up and using your network.
For information about See this publication Publication number
Using Ethernet for industrial control EtherNet/IP Performance and Application Guide ENET-AP001
EtherNet/IP media EtherNet/IP Media Planningand Installation Guide ENET-IN001
1756-ENBT module ControlLogix EtherNet/IP Bridge Module Installation Instructions 1756-IN019
ControlLogix chassis ControlLogix Chassis Installation instructions 1756-IN080
ControlLogix power supplies ControlLogix Power Supplies Installation Instructions 1756-5.67 (PA72/PB72)
1756-5.78 (PA75/PB75)
Logix5550 programmable controllers Logix5550 Controller User Manual 1756-UM012
ControlLogix analog I/O modules ControlLogix Analog I/O Users Manual 1756-6.5.9
ControlLogix digital I/O modules ControlLogix Digital I/O Users Manual 1756-UM058
FLEX I/O EtherNet/IP adapter FLEX I/O EtherNet/IP Adapter Installation Instructions 1794-IN082
FLEX I/O EtherNet/IP Adapter User Manual 1794-UM006
FLEX I/O input and output modules FLEX I/O and FLEX Integra Technical Data Manual 1794-2.1
RSLogix 5000 programming software(1) Getting Results with RSLogix5000 LG5000-GR001
RSLinx communications software(1) RSLinx Lite User’s Guide 9399-UM007
(1) See also the tutorials and Help menusprovided with this software.
TIP Many of the above publications are available online
from the Automation Bookstore:
http://www.theautomationbookstore.com.
TIP Rockwell Software products are provided with
extensive tutorials and online Help. We recommend
that you use the tutorials and Help menus to learn
about these products.
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
Notes:

iPublication 1756-UM050A-EN-P - December 2001
Table of Contents
Chapter 1
About the 1756-ENBT Module
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Module Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Hardware/Software Compatibility . . . . . . . . . . . . . . . . . . . . . . 1-2
What the Module Does. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Support of Rack Optimized and Direct Connections. . . . . . . . . 1-2
Mixing Rack Optimized and Direct Connections. . . . . . . . . 1-3
Use of the Control and Information Protocol (CIP) . . . . . . . . . 1-4
Understanding the Producer/Consumer Model. . . . . . . . . . . . . 1-4
Specifying the Requested Packet Interval (RPI) . . . . . . . . . . . . 1-5
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Chapter 2
Installing the 1756-ENBT Module
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Identifying Module Components. . . . . . . . . . . . . . . . . . . . . . . 2-2
Preparing the Chassis for Module Installation . . . . . . . . . . . . . 2-2
Determining Module Slot Location . . . . . . . . . . . . . . . . . . . . . 2-3
Installing the Module in the Chassis . . . . . . . . . . . . . . . . . . . . 2-4
Removing or Replacing the Module (when applicable) . . . . . . 2-5
Installing or Removing the Module Under Power. . . . . . . . . . . 2-6
Wiring the RJ45 Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Connecting the Module to the Network. . . . . . . . . . . . . . . . . . 2-7
Applying Chassis Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Checking Power Supply and Module Status. . . . . . . . . . . . . . . 2-8
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Chapter 3
Before You Configure Your
Module
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Ethernet Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Transmission Control Protocol/Internet Protocol (TCP/IP) . 3-1
User Datagram Protocol (UDP) . . . . . . . . . . . . . . . . . . . . . 3-2
EtherNet/IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Simple Network Management Protocol (SNMP) . . . . . . . . . 3-2
Configuration Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
IP Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Gateways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Subnet Mask. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
For More Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Chapter 4
Configuring the 1756-ENBT
Module
What This Chapter Contains . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Using the Rockwell BootP Utility . . . . . . . . . . . . . . . . . . . . . . 4-2
Using Force IP Renew To Reconfigure a Device. . . . . . . . . 4-4
Saving the Relation List . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
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Using RSLinx Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Using a Third Party BootP Server . . . . . . . . . . . . . . . . . . . . . 4-10
Using DHCP Software to Configure Your Module . . . . . . . . . 4-12
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12
Chapter 5
Using Rack Optimized I/O
About the Example Application . . . . . . . . . . . . . . . . . . . . . . . 5-1
Set Up the Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Create the Example Application . . . . . . . . . . . . . . . . . . . . . . . 5-3
Add the Local Ethernet Bridge to the I/O Configuration . . . 5-4
Add the Remote Ethernet Bridge to the I/O Configuration . 5-6
Add the Remote I/O Modules to the I/O Configuration . . . 5-8
Add the Remote Digital Input Module . . . . . . . . . . . . . 5-8
Add the Remote Digital Output Module . . . . . . . . . . . 5-10
Edit the Controller Tags . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Create the Ladder Program . . . . . . . . . . . . . . . . . . . . . . . 5-14
Download the Program to the Controller . . . . . . . . . . . . . 5-15
Test the Example Application . . . . . . . . . . . . . . . . . . . . . . . . 5-16
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-17
Chapter 6
Using Analog I/O with Direct
Connection
About the Example Application . . . . . . . . . . . . . . . . . . . . . . . 6-1
Set Up the Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Create the Example Application . . . . . . . . . . . . . . . . . . . . . . . 6-3
Add the Remote Analog I/O Module
to the I/O Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Edit the Controller Tags . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Modify the Ladder Program. . . . . . . . . . . . . . . . . . . . . . . 6-10
Download the Program. . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Test the Example Application . . . . . . . . . . . . . . . . . . . . . . . . 6-12
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Chapter 7
Using Produced
and Consumed Tags
About the Example Application . . . . . . . . . . . . . . . . . . . . . . . 7-1
Set Up the Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Create the Producer Application . . . . . . . . . . . . . . . . . . . . . . . 7-3
Create the Producer Tags . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Create the Producer Ladder Program . . . . . . . . . . . . . . . . . 7-6
Download the Producer Application . . . . . . . . . . . . . . . . . 7-7
Create the Consumer Application . . . . . . . . . . . . . . . . . . . . . . 7-8
Create the Consumer Controller. . . . . . . . . . . . . . . . . . . . . 7-8
Add the Producer to the Consumer’s I/O Configuration . . . 7-9
Add the Local Ethernet Bridge to the I/O Configuration 7-9
Add the Remote Ethernet Bridge
to the I/O Configuration . . . . . . . . . . . . . . . . . . . . . . 7-11
Add the Remote (Producer) Controller
to the I/O Configuration . . . . . . . . . . . . . . . . . . . . . . 7-13

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Table of Contents iii
Create the Consumer Tags. . . . . . . . . . . . . . . . . . . . . . . . 7-15
Download the Configuration to the Consumer . . . . . . . . . 7-18
Test the Messaging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-19
What’s Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-19
Chapter 8
Interfacing with FLEX I/O
About the Example Application . . . . . . . . . . . . . . . . . . . . . . . 8-1
Set Up the Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Create the Example Application . . . . . . . . . . . . . . . . . . . . . . . 8-3
Configure the I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Add the Local EtherNet/IP Bridge to the I/O Configuration. 8-4
Add the FLEX I/O Adapter to the I/O Configuration. . . . . . 8-6
Add the FLEX I/O Modules to the I/O Configuration . . . . . 8-8
Add the Digital Input Module . . . . . . . . . . . . . . . . . . . 8-8
Add the Digital Output Module . . . . . . . . . . . . . . . . . 8-10
Edit the Controller Tags . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
Create the Ladder Program . . . . . . . . . . . . . . . . . . . . . . . . . . 8-13
Download the Program to the Controller . . . . . . . . . . . . . 8-14
Test the Example Application . . . . . . . . . . . . . . . . . . . . . . . . 8-15
Appendix A
Troubleshooting
Interpreting the Status Indicators. . . . . . . . . . . . . . . . . . . . . . . A-1
NET (Network) Status Indicator. . . . . . . . . . . . . . . . . . . . . A-1
Link Status Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
OK Status Indicator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Appendix B
1756-ENBT Module Web Pages
Web Page Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1
Module Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
TCP/IP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Diagnostic Information . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
Backplane and Connection Manager . . . . . . . . . . . . . . B-3
Network Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-4
Miscellaneous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-4
Chassis Who. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-5
Appendix C
Configuring the RSLinx Ethernet
Communication Driver
What This Appendix Contains. . . . . . . . . . . . . . . . . . . . . . . . . C-1
Installing the RSLinx Software. . . . . . . . . . . . . . . . . . . . . . . . . C-1
Configuring the AB_ETH Driver . . . . . . . . . . . . . . . . . . . . . . . C-2
Appendix D
Example Network Configurations
What This Appendix Contains. . . . . . . . . . . . . . . . . . . . . . . . D-1
Small System Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-2
Expanded System with FLEX I/O . . . . . . . . . . . . . . . . . . . . . D-3
Larger Control Networks. . . . . . . . . . . . . . . . . . . . . . . . . . . . D-4
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Table of Contents iv
Appendix E
Autonegotiation Requirements
Manual Configuration on an Ethernet Switch. . . . . . . . . . . . . . E-1
Changing Ports on an Ethernet Switch. . . . . . . . . . . . . . . . . . . E-1
Index

1Publication 1756-UM050A-EN-P - December 2001
Chapter 1
About the 1756-ENBT Module
What This Chapter Contains
This chapter provides an overview of the ControlLogix 1756-ENBT
module, its primary features, what it does, and how to use it. You will
need to understand the concepts discussed in this chapter to configure
your EtherNet/IP Bridge module and use it in a control system. The
following table lists where to find specific information in this chapter.
.
Module Features
The 1756-ENBT module’s features include:
•use EtherNet/IP messages encapsulated within standard
TCP/UDP/IP protocol
•common application layer with ControlNet and DeviceNet
•interfacing via Category 5 twisted pair cable
•Half/Full Duplex 10 Mbit or 100 Mbit operation
•removal or insertion under power
•number of modules per chassis limited only by chassis size
•communication to and from other ControlLogix modules in the
same chassis
•communication supported by RSLinx software
•configurable via RSLinx or standard BootP tools
•no network scheduling required
•no routing tables required
For information about See page
Module Features 1-1
What the Module Does 1-2
Hardware/Software Compatibility 1-2
Support of Rack Optimized andDirect Connections 1-2
Mixing Rack Optimized and Direct Connections 1-3
Use of the Control andInformation Protocol (CIP) 1-4
Understanding the Producer/Consumer Model 1-4
Specifying the Requested Packet Interval (RPI) 1-5
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1-2 About the 1756-ENBT Module
Hardware/Software
Compatibility
The 1756-ENBT module is compatible with the following product’s
firmware versions and software releases. Contact Rockwell
Automation if you need software or firmware upgrades to use this
equipment.:
What the Module Does
The 1756-ENBT module performs two primary tasks:
1. Control of real time I/O data (also known as “implicit messaging”)
in conjunction with a Logix controller. The 1756-ENBT module may
serve as a bridge between I/O modules and the network, or as a
bridge between the controller and the network.
2. Support of messaging data for configuration and programming
information, operator interfaces, etc. (also known as “explicit
messaging.”).
Support of Rack Optimized
and Direct Connections
The 1756-ENBT module supports both Rack Optimized and Direct
Connections. A direct connection is a real-time data transfer link
between the controller and the device that occupies the slot that the
configuration data references. A rack optimized connection is a
grouping of data from more than one I/O module into a single block
of data sent over a single connection.
Product Firmware Version/
Software Release
1756-ENBT module 1.x or higher
1756-ENET/A/B 1.18 or higher
1794-AENT 1.x
Logix 5550 Controller 8.1 or higher
PanelView All Ethernet compatible models
RSLogix 5000 software 8.1 or higher
RSLinx software 2.3 or higher
I/O I/O
L
5
5
5
0
E
N
B
T
EtherNet/IP Network
E
N
B
T
I/O I/O
E
N
B
T
I/O I/O
E
N
B
T

Publication 1756-UM050A-EN-P - December 2001
About the 1756-ENBT Module 1-3
Rack optimized connections reduce the total number of connections
needed to transfer data when using many I/O modules in a system.
The following example illustrates the benefit of rack optimized
connections.
Assume you have set up a system that contains 10 discrete I/O
modules in a remote ControlLogix chassis. If you use direct
connections to transfer data to each of the these I/O modules, you
need 10 connections to transfer all of the data, one to each of the ten
I/O modules. If you use a rack-optimized connection to transfer the
data, you only need a single connection –the connection to the
1756-ENBT module.
See the EtherNet/IP Performance and Application Guide, publication
number ENET-AP001, for more information on connections.
Mixing Rack Optimized and Direct Connections
You can mix communication formats for different I/O modules in the
same chassis. I/O modules set up to use Rack Optimization will
communicate at the rate of the RPI (requested packet interval)
configured for the 1756-ENBT module. I/O modules configured for
direct communication will communicate at their set RPI and ignore the
1756-ENBT module’s RPI.
IMPORTANT Although rack optimized connections offer an
efficient way to use resources, there are a few
limitations on their use:
•You can only use rack optimized connections to
send data to and from discrete digital I/O
modules. Analog I/O requires direct connections.
•Rack optimized connections can contain I/O data
and status information only. Additional module
information, such as diagnostics, is not available
through a rack-optimized connection.
•All data is sent at the same time at the RPI rate of
the 1756-ENBT module.
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1-4 About the 1756-ENBT Module
Use of the Control and
Information Protocol (CIP)
The 1756-ENBT module uses the Control and Information Protocol
(CIP). CIP is the application layer protocol specified for EtherNet/IP,
the Ethernet Industrial Protocol, as well as for ControlNet and
DeviceNet. It is a message-based protocol that implements a relative
path to send a message from the “producing”device in a system to the
“consuming”devices.
The producing device contains the path information that steers the
message along the proper route to reach its consumers. Since the
producing device holds this information, other devices along the path
simply pass this information; they do not need to store it. This has two
significant benefits:
•You do not need to configure routing tables in the bridging
module, which greatly simplifies maintenance and module
replacement.
•You maintain full control over the route taken by each message,
which enables you to select alternative paths for the same end
device.
Understanding the
Producer/Consumer Model
CIP uses the “producer/consumer”networking model, replacing the
old source/destination (master/slave) model. The producer/consumer
model reduces network traffic and increases speed of transmission. In
traditional I/O systems, controllers poll input modules to obtain their
input status. In the CIP system digital input modules are not polled by
a controller. Instead, they produce (“multicast”) their data either upon
a change of state (COS) or periodically. The frequency of update
depends upon the options chosen during configuration and where on
the network the input module resides. The input module, therefore, is
a producer of input data and the controller is a consumer of the data.
The controller can also produce data for other controllers to consume.
The produced and consumed data is accessible by multiple controllers
over the ControlLogix backplane and over the EtherNet/IP network.
This data exchange conforms to the producer/consumer model.

Publication 1756-UM050A-EN-P - December 2001
About the 1756-ENBT Module 1-5
You configure the producer and consumer by creating controller
scoped tags using RSLogix 5000 software (see chapter 7).
Specifying the Requested
Packet Interval (RPI)
The RPI is the update rate specified for a particular piece of data on
the network. The RPI can be specified for an entire rack (using a rack
optimized connection) or for a particular module (using direct
connection). When you add a module to the I/O configuration of a
controller, you must enter the RPI as a parameter. ‘This value specifies
how often to produce the data for that module. For example, if you
specify an RPI of 50ms, it means that every 50ms the I/O module
should send its data to the controller or that the controller should send
its data to the I/O module.
RPIs are only used for modules that produce data. For example a local
1756-ENBT module (i.e., an ENB module in the same chassis as the
controller) does not require an RPI because it is not a data-producing
member of the system; it is used only as a bridge to remote racks.
What’s Next?
The following chapter describes how to physically install the
EtherNet/IP Bridge module and connect it to the network.
Tag Type Description Specify Using RSLogix5000 Software
Produced(1) Tags that the controller produced for other
nodes to consume. Enabled for producing Number of consumers allowed
Consumed(1) Tagswhosevaluesareproducedbyanother
controller. Name ofcontroller that owns the tag the local controller wants to consume
Tag name or instance that the local controller wants to consume
Data type of the tag toconsume
Update interval of how often the local controller consumes the tag
data
(1) Produced and consumed tags must be controller-scoped tags of DINT or REAL data type, or in an arrayor structure.
AB Parts

Publication 1756-UM050A-EN-P - December 2001
1-6 About the 1756-ENBT Module