Allen-Bradley 1756-L5 Owner's manual

Programming Manual
Logix5000 Controllers Messages
Catalog Numbers 1756-L1, 1756-L55, 1756-L61, 1756-L62, 1756-L63, 1769-L31, 1769-L32C, 1769-L32E, 1769-L35CR, 1769-L35E,
1789-L60, 1794-L34, PowerFlex 700S/SE

Important User Information
Solid-state equipment has operational characteristics differing from those of electromechanical equipment. Safety
Guidelines for the Application, Installation and Maintenance of Solid State Controls (publication SGI-1.1 available from
your local Rockwell Automation sales office or online at http://www.rockwellautomation.com/literature/) describes some
important differences between solid-state equipment and hard-wired electromechanical devices. Because of this difference,
and also because of the wide variety of uses for solid-state equipment, all persons responsible for applying this equipment
must satisfy themselves that each intended application of this equipment is acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from
the use or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and
requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or
liability for actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or
software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation,
Inc., is prohibited.
Throughout this manual, when necessary, we use notes to make you aware of safety considerations.
Allen-Bradley, Rockwell Automation, Logix5000, RSLogix 5000, ControlLogix, GuardLogix, CompactLogix, PowerFlex, SoftLogix, Rockwell Software, PLC-2, PLC-3, PLC-5, SLC, SLC 500, and TechConnect are
trademarks of Rockwell Automation, Inc.
Trademarks not belonging to Rockwell Automation are property of their respective companies.
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. Attentions help you identify a hazard, avoid a hazard, and recognize the consequence
SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous voltage may be
present.
BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may reach
dangerous temperatures.
IMPORTANT Identifies information that is critical for successful application and understanding of the product.

Rockwell Automation Publication 1756-PM012D-EN-P - November 2011 3
Summary of Changes
This manual contains new and updated information. Changes throughout this
revision are marked by change bars, as shown to the right of this paragraph.
New and Updated Information
This table contains the changes made to this revision.
Topic Page
Added information on the Large Connection checkbox to second footnote under
table.
11
Added a new row to the table that discusses “If the MSG instructions are to” —
New row starts with “Same device and cached and large connection”.
12
Added additional information to the example given for Share a Connection. 12
Changed Destination to Destination Element to reflect changes to the UI. 14
Updated instructions on setting the path to a remote controller. 27
Updated the screen shot to reflect changes to the UI. 30
Changed Destination Tag to Destination Element and Source Tag to Source
Element to reflect changes to the UI.
30

4 Rockwell Automation Publication 1756-PM012D-EN-P - November 2011
Summary of Changes
Notes:

Rockwell Automation Publication 1756-PM012D-EN-P - November 2011 5
Table of Contents
Summary of Changes New and Updated Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Table of Contents
Preface
Purpose of This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 1
Controller Messages
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Supported Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Message Queue. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Cache List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Unconnected Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Get or Set the Number of Unconnected Buffers. . . . . . . . . . . . . . . . . . . . . 13
Get the Number of Unconnected Buffers . . . . . . . . . . . . . . . . . . . . . . . 14
Set the Number of Unconnected Buffers . . . . . . . . . . . . . . . . . . . . . . . 14
Convert Between INTs and DINTs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Chapter 2
Manage Multiple Messages
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Message Manager Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Initialize the Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Restart the Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Send the First Group of MSGs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Enable the Second Group of MSGs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Send the Second Group of MSGs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Enable the Next Group of MSGs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Send the Next Group of MSGs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Chapter 3
Send a Message to Multiple
Controllers
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Set Up the I/O Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Define Your Source and Destination Elements. . . . . . . . . . . . . . . . . . . . . . 24
Create the MESSAGE_ CONFIGURATION Data Type. . . . . . . . . . . 25
Create the Configuration Array . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Get the Size of the Local Array . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Load the Message Properties for a Controller . . . . . . . . . . . . . . . . . . . . . . . 29
Configure the Message. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Step to the Next Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Restart the Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Index

6 Rockwell Automation Publication 1756-PM012D-EN-P - November 2011
Table of Contents
Notes:

Rockwell Automation Publication 1756-PM012D-EN-P - November 2011 7
Preface
Purpose of This Manual
This manual shows how to program message (MSG) instructions to and from
Logix5000 controllers. This manual is one of a set of related manuals that show
common procedures for programming and operating Logix5000 controllers.
For a complete list of common procedures manuals, see the
Logix5000 Controllers Common Procedures Programming Manual, publication
1756-PM001.
The term Logix5000 controller refers to any controller that is based on the
Logix5000 operating system, such as:
•CompactLogix controllers.
•ControlLogix controllers.
•DriveLogix controllers.
•FlexLogix controllers.
•SoftLogix5800 controllers.
Additional Resources
These documents contain additional information concerning related products
from Rockwell Automation.
You can view or download publications at http://www.rockwellautomation.com/
literature/. To order paper copies of technical documentation, contact your local
Allen-Bradley distributor or Rockwell Automation sales representative.
Resource Description
Industrial Automation Wiring and Grounding Guidelines,
publication 1770-4.1
Provides general guidelines for installing a Rockwell
Automation industrial system.
Product Certifications website, http://www.ab.com Provides declarations of conformity, certificates, and
other certification details.

8 Rockwell Automation Publication 1756-PM012D-EN-P - November 2011
Preface
Notes:

Rockwell Automation Publication 1756-PM012D-EN-P - November 2011 9
Chapter 1
Controller Messages
Introduction This section describes how to transfer data between controllers (send or receive
data) by executing a message (MSG) instruction. Cache connections and buffers
are explained so you can correctly program the controller.
Supported Data Types
The following data types are supported when sending CIP messages:
•SINT
•INT
•DINT
•LINT
•REAL
In addition, any structure type that is predefined, module-defined, or user-
defined can be used for sending a message.
See page 16 for more information on INTs and DINTs.
For complete details on programming a message instruction, see the Logix5000
Controllers General Instruction Reference Manual,
publication 1756-RM003.
EXAMPLE Execute a Message (MSG) Instruction
If count_send = 1 and count_msg.EN = 0 (MSG instruction is not already enabled), then execute a MSG instruction that sends data to another controller.
count_send
/
count_msg.en
EN
DN
ER
Type - Unconfigured
Message Controlcount_msg ...
MSG

10 Rockwell Automation Publication 1756-PM012D-EN-P - November 2011
Chapter 1 Controller Messages
This diagram shows how the controller processes MSG instructions.
Message Queue
The message queue holds up to 48 MSG instructions, including those that you
configure as a block-transfer read or block-transfer write. When the queue is full,
an instruction tries to enter the queue on each subsequent scan of the instruction,
as shown below.
Description
The controller scans the MSG instruction and its rung-condition-in goes true. The message will pass to a throttle, which has 16 positions. If the throttle is full, the message
will stay enabled but is held until another controller scan.
The System-overhead time slice executes and the message is pulled from the throttle to the message queue.
If the MSG instruction Then the MSG instruction
Does not use a connection or the connection was not previously cached.
Uses a connection and the connection is cached
Uses an unconnected buffer to establish communication with the
destination device.
Does not use an unconnected buffer.
Communication occurs with the destination device.
Message Queue
Yes
Unconnected Outgoing
Buffers (10 to 40)
No
Destination Device
Cached?
48
total
1 2
4
3
Cache List
MSG
Throttle
16
1
2
3
4
Rung-condition-in false true false
.EN bit off on
.EW bit off on
1 2 3 4