Rockwell Automation DAG6.5.8 User Manual

SCADA System

Application Guide

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 http://www.ab.com/manuals/gi) 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 we use notes to make you aware of safety considerations.

sales office or online at

WARNING

IMPORTANT

ATTENTION

SHOCK HAZARD

BURN HAZARD

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.

Identifies information that is critical for successful application and understanding of the product.

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

• recognize the consequence

Labels may be located on or inside the drive to alert people that dangerous voltage may be present.

Labels may be located on or inside the drive to alert people that surfaces may be dangerous temperatures.

Summary of Changes

The information below summarizes the changes to this manual since the last printing.

To help you find new and updated information in this release of the manual, we have included change bars as shown to the right of this paragraph.

For information on See

Removing Configuring Classic PLC-5 Processors with 1785-KE Modules chapter

Add in additional publications Preface Designing communication for DF1 Radio Modem 1-17 through 1-19 Modbus RTU 3-46 through 3-57 Data Logging 3-58 through 3-69 Conditions that will erase the data retrieval file 3-69 DF1 Radio Modem 4-7 through 4-8 Configuring a Radio Modem station 4-27 through 4-32 Rockwell Automation modems 8-3 through 8-4 Configuring modems for PLC-5, SLC, and Logix processors 10-3 Configuring modems for MicroLogix 1100/1200/1500

controllers Communicating over the telephone line 10-4 through 10-8 Remotely programming Allen-Bradley processors over a

telemetry network DF1 Radio Modem B-7 Third party suppliers Appendix C

10-4

Chapter 11

1 Publication AG-UM008C-EN-P - February 2005

2 Summary of Changes

Publication AG-UM008C-EN-P - February 2005

Designing Communication

Preface

What SCADA Information Is Available?. . . . . . . . . . . . . . . . 1-1

Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Contents of this Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Terms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Address Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Chapter 1

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Choosing a Polling Mode for DF1 Half-Duplex Master . . . . 1-2

Message-Based Polling Mode . . . . . . . . . . . . . . . . . . . . 1-2

Standard Polling Mode . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

About Polled Report-by-Exception . . . . . . . . . . . . . . . . 1-4

About Slave-to-Slave Messaging . . . . . . . . . . . . . . . . . . 1-5

Addressing Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

Communication Scheme Design Using Standard-Mode . . . . 1-8

Designing a Polling Scheme . . . . . . . . . . . . . . . . . . . . 1-11

Planning for Timing Issues . . . . . . . . . . . . . . . . . . . . . 1-13

Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . 1-13

Communication Scheme Design Using

Message-Based Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

Designing Communication

for DF1 Full-Duplex Protocol. . . . . . . . . . . . . . . . . . . . . . . 1-16

Designing Communication for DF1 Radio Modem Protocol. 1-17

Determining When to Use DF1 Radio Modem Protocol . 1-17

What to Do Next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19

Chapter 2

Configuring Enhanced PLC-5 Processors

1 Publication AG-UM008C-EN-P - February 2005

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Installing the Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Configuring a DF1 Half-Duplex Standard Mode

Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Define the Communication Driver Characteristics . . . . . 2-5

Displaying System (Master) Channel Status . . . . . . . . . . 2-7

Create Station Lists. . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Monitor Active Stations . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Configuring a DF1 Half-Duplex Message-based

Mode Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

Configuring the Processor as a Slave Station. . . . . . . . . . . . 2-15

Displaying Slave System Channel Status . . . . . . . . . . . . 2-18

2 Table of Contents

Configuring MicroLogix 1100/1200/1500 Controllers

Configuring the Processor as a Station on a

Point-to-Point Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20

Displaying Point-to-Point System Channel Status . . . . . . 2-22

Messaging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23

Master Station to Slave Station . . . . . . . . . . . . . . . . . . . 2-23

Polled Report-by-Exception . . . . . . . . . . . . . . . . . . . . . 2-23

Processor-to-Processor . . . . . . . . . . . . . . . . . . . . . . . . . 2-24

Considerations When Configuring MSG Control Blocks . 2-25

Example MSG Control Blocks. . . . . . . . . . . . . . . . . . . . 2-26

Chapter 3

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Installing the Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

MicroLogix 1200/1500 Channel 0 Cable Pinouts - User

Supplied Optical Isolator . . . . . . . . . . . . . . . . . . . . . . . 3-3

MicroLogix 1200/1500 Channel 0 Cable Pinouts -

Allen-Bradley Supplied Optical Isolator. . . . . . . . . . . . . 3-4

MicroLogix 1500 LRP Channel 1 Cable Pinouts . . . . . . . 3-5

Using Modems that Support DF1 Communication Protocols 3-6

Dial-up Phone Modems . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Leased-Line Modems . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Radio Modems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Line Drivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

Modem Control Line Operation . . . . . . . . . . . . . . . . . . . . . 3-8

DF1 Full-Duplex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

DF1 Half-Duplex Slave. . . . . . . . . . . . . . . . . . . . . . . . . 3-8

DF1 Half Duplex Master. . . . . . . . . . . . . . . . . . . . . . . . 3-9

DF1 Radio Modem. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Configuring DF1 Half-Duplex Channel 0 Parameters. . . . . . 3-11

RTS Send Delay and RTS Off Delay . . . . . . . . . . . . . . . 3-11

Configuring a Standard-Mode DF1 Half-Duplex

Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12

Minimum DF1 Half-Duplex Master Channel 0

ACK Timeout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

Determining Minimum Master ACK Timeout . . . . . . . . . 3-15

DF1 Half-Duplex Master Channel Status . . . . . . . . . . . . 3-17

Monitor Active Stations. . . . . . . . . . . . . . . . . . . . . . . . . 3-18

Configuring a Message-based Mode DF1

Half-Duplex Master Station . . . . . . . . . . . . . . . . . . . . . . . . 3-19

Configuring a Slave Station . . . . . . . . . . . . . . . . . . . . . . . . 3-22

Configuring Poll Timeout . . . . . . . . . . . . . . . . . . . . . . . . . 3-25

DF1 Half-Duplex Slave Channel Status . . . . . . . . . . . . . 3-25

Configuring a Radio Modem Station. . . . . . . . . . . . . . . . . . 3-27

DF1 Radio Modem Channel Status . . . . . . . . . . . . . . . . 3-30

Configuring the Store & Forward Table. . . . . . . . . . . . . 3-31

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Table of Contents 3

Configuring a Station on a Point-to-Point Link . . . . . . . . . . 3-33

DF1 Full-Duplex Channel Status . . . . . . . . . . . . . . . . . . 3-35

DF1 Messaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-36

Master Station to Slave Station . . . . . . . . . . . . . . . . . . . 3-36

Polled Report-by-Exception . . . . . . . . . . . . . . . . . . . . . 3-36

Processor-to-Processor . . . . . . . . . . . . . . . . . . . . . . . . . 3-37

Considerations When Configuring MSG

Control Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-37

Example MSG Control Blocks . . . . . . . . . . . . . . . . . . . . . . 3-42

Modbus RTU Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-46

Modbus RTU Master. . . . . . . . . . . . . . . . . . . . . . . . . . . 3-46

Modbus RTU Slave. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-47

Modbus RTU Master Configuration . . . . . . . . . . . . . . . . 3-48

Modbus RTU Master Configuration . . . . . . . . . . . . . . . . 3-49

Modbus RTU Slave Configuration . . . . . . . . . . . . . . . . . 3-50

Modbus Slave Memory Map . . . . . . . . . . . . . . . . . . . . . 3-51

Modbus Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-53

Modbus Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54

Configuring a Modbus Message . . . . . . . . . . . . . . . . . . 3-56

Data Logging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-58

Queues and Records . . . . . . . . . . . . . . . . . . . . . . . . . . 3-58

Example Queue 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59

Example Queue 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

Configuring Data Log Queues . . . . . . . . . . . . . . . . . . . 3-62

DLG - Data Log Instruction. . . . . . . . . . . . . . . . . . . . . . 3-64

Data Log Status File . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-64

Retrieving (Reading) Records . . . . . . . . . . . . . . . . . . . . 3-66

Accessing the Retrieval File . . . . . . . . . . . . . . . . . . . . . 3-67

Retrieval Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-67

Information for Creating Your Own Application . . . . . . 3-68

Conditions that Will Erase the Data Retrieval File . . . . . . . . 3-69

Configuring SLC 5/03, 5/04, and 5/05 Processors

Chapter 4

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Installing the Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Using Modems that Support DF1 Communication Protocols 4-3

Dial-up Phone Modems . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Leased-Line Modems . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Radio Modems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Line Drivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Modem Control Line Operation . . . . . . . . . . . . . . . . . . . . . 4-5

DF1 Full-Duplex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

DF1 Half-Duplex Slave. . . . . . . . . . . . . . . . . . . . . . . . . 4-6

DF1 Half Duplex Master. . . . . . . . . . . . . . . . . . . . . . . . 4-6

DF1 Radio Modem. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7

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4 Table of Contents

Configuring DF1 Half-Duplex Channel 0 Parameters. . . . . . 4-8

RTS Send Delay and RTS Off Delay . . . . . . . . . . . . . . . 4-8

Configuring a Standard-Mode DF1 Half-Duplex

Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10

Minimum DF1 Half-Duplex Master Channel 0

ACK Timeout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13

Determining Minimum Master ACK Timeout . . . . . . . . . 4-14

DF1 Half-Duplex Master Channel Status . . . . . . . . . . . . 4-16

Monitor Active Stations. . . . . . . . . . . . . . . . . . . . . . . . . 4-17

Configuring a Message-based Mode DF1 Half-Duplex

Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18

Configuring a Slave Station . . . . . . . . . . . . . . . . . . . . . . . . 4-22

Configuring Channel 0 Poll Timeout . . . . . . . . . . . . . . . . . 4-25

DF1 Half-Duplex Slave Channel Status . . . . . . . . . . . . . 4-25

Configuring a Radio Modem Station. . . . . . . . . . . . . . . . . . 4-27

DF1 Radio Modem Channel Status . . . . . . . . . . . . . . . . 4-30

Configuring the Store & Forward Table. . . . . . . . . . . . . 4-31

Configuring a Station on a Point-to-Point Link . . . . . . . . . . 4-33

DF1 Full-Duplex Channel Status . . . . . . . . . . . . . . . . . . 4-35

Messaging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-37

Master Station to Slave Station . . . . . . . . . . . . . . . . . . . 4-37

Polled Report-by-Exception . . . . . . . . . . . . . . . . . . . . . 4-37

Processor-to-Processor . . . . . . . . . . . . . . . . . . . . . . . . . 4-38

Considerations When Configuring MSG

Control Blocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-38

Example MSG Control Blocks . . . . . . . . . . . . . . . . . . . . . . 4-43

Configuring SLC 500 Processors with 1747-KE Interface Modules

Publication AG-UM008C-EN-P - February 2005

Chapter 5

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Installing the Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Installing the 1747-KE

Interface Module. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Configuring the Processor . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

Configuring the 1747-KE

Interface Module. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4

Prepare to Configure the Driver . . . . . . . . . . . . . . . . . . 5-4

Configure the DF1 Protocol Driver . . . . . . . . . . . . . . . . 5-7

Save the Configuration. . . . . . . . . . . . . . . . . . . . . . . . . 5-10

Messaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11

Polled Report-by-Exception . . . . . . . . . . . . . . . . . . . . . 5-11

Processor-to-Processor . . . . . . . . . . . . . . . . . . . . . . . . . 5-12

Considerations When Configuring MSG Control Blocks . 5-12

Example MSG Control Blocks. . . . . . . . . . . . . . . . . . . . 5-13

Configuring MicroLogix 1000 Controllers

Table of Contents 5

Chapter 6

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Installing the Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

Isolated Connections . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

Automatic Protocol Switching . . . . . . . . . . . . . . . . . . . . . . 6-4

Using Modems that Support DF1 Communication Protocols 6-5

Dial-up Phone Modems . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Leased-Line Modems . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Radio Modems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

Line Drivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7

Modem Control Line Operation . . . . . . . . . . . . . . . . . . . . . 6-7

DF1 Full-Duplex Operation . . . . . . . . . . . . . . . . . . . . . 6-7

DF1 Half-Duplex Slave Operation. . . . . . . . . . . . . . . . . 6-7

DF1 Slave on a Multi-drop Link . . . . . . . . . . . . . . . . . . 6-8

Ownership Timeout. . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9

Configuring a Slave Station . . . . . . . . . . . . . . . . . . . . . . . . 6-10

Configuring RTS Send Delay and RTS Off Delay. . . . . . . . . 6-11

Configuring Poll Timeout . . . . . . . . . . . . . . . . . . . . . . . . . 6-12

Configuring a Point-to-Point Station . . . . . . . . . . . . . . . . . . 6-13

Messaging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14

Polled Report-by-Exception . . . . . . . . . . . . . . . . . . . . . 6-15

Processor-to-Processor . . . . . . . . . . . . . . . . . . . . . . . . . 6-15

Considerations When Configuring MSG Control Blocks . 6-16

Configuring MSG Block Message Timeout. . . . . . . . . . . 6-17

Example MSG Control Blocks. . . . . . . . . . . . . . . . . . . . 6-18

Configuring Logix Controllers

Chapter 7

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2

Installing the Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3

Using Modems that Support DF1 Communication Protocols 7-3

Dial-up Phone Modems . . . . . . . . . . . . . . . . . . . . . . . . 7-4

Leased-Line Modems . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4

Radio Modems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4

Line Drivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5

Configuring the Controller to Use the Serial Port . . . . . . . . 7-5

Modem Control Line Operation . . . . . . . . . . . . . . . . . . . . . 7-7

No Handshake Selected . . . . . . . . . . . . . . . . . . . . . . . . 7-7

Full-Duplex Selected . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7

Half-Duplex Selected with Continuous Checked . . . . . . 7-7

Half-Duplex Selected with Continuous Carrier

Unchecked . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7

Configuration Considerations for RTS Send and Off Delays. 7-8

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6 Table of Contents

Configuring a Standard-Mode DF1 Half-Duplex

Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8

Configuring a Master Station for Standard Polling Mode . . . 7-9

Minimum DF1 Half-Duplex Master ACK Timeout . . . . . 7-11

Determining Minimum Master Serial Port ACK Timeout . 7-12

DF1 Half-Duplex Master Diagnostic Counter . . . . . . . . . . . 7-13

Create Polling List(s) . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15

Monitor Active Stations. . . . . . . . . . . . . . . . . . . . . . . . . 7-16

Configuring a Message-Based Mode DF1 Half-Duplex

Master Station . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16

Configuring a Master Station for Message-based

Polling Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-17

Configuring the Controller as a Slave Station . . . . . . . . . . . 7-19

Configuring Slave Poll Timeout . . . . . . . . . . . . . . . . . . . . . 7-20

DF1 Half-Duplex Slave Diagnostic Counters. . . . . . . . . . . . 7-20

Configuring the Controller as a Station on a

Point-to-Point Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-22

DF1 Point-to-Point Diagnostic Counters . . . . . . . . . . . . . . . 7-24

Accessing DF1 Diagnostic Counters . . . . . . . . . . . . . . . . . . 7-25

Messaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-28

Master Station to Slave Station . . . . . . . . . . . . . . . . . . . 7-28

Polled Report-by-Exception . . . . . . . . . . . . . . . . . . . . . 7-28

Controller-to-Controller . . . . . . . . . . . . . . . . . . . . . . . . 7-29

Considerations When Configuring MSG Control Blocks . 7-30

Example MSG Control Blocks . . . . . . . . . . . . . . . . . . . . . . 7-31

Logix Controller Error Codes for PLC and SLC Messages . . . 7-38

Configuring Modems

Publication AG-UM008C-EN-P - February 2005

Chapter 8

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1

Installing a Modem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1

Configuration Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2

Telephone Modem Configurations . . . . . . . . . . . . . . . . . . . 8-2

Rockwell Automation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

DATA-LINC Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5

DLM4300. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5

LLM1000-2 and LLM1000-4 . . . . . . . . . . . . . . . . . . . . . . 8-6

DLM4000. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9

DLM4100-SLC and DLM4100-PLC . . . . . . . . . . . . . . . . . 8-10

Miille Applied Research Company, Inc. (MARC) . . . . . . . . . 8-11

MARC Model 166-101. . . . . . . . . . . . . . . . . . . . . . . . . . 8-12

MARC Model 137-001. . . . . . . . . . . . . . . . . . . . . . . . . . 8-14

MARC Model 148-001. . . . . . . . . . . . . . . . . . . . . . . . . . 8-16

MARC Model 166-100. . . . . . . . . . . . . . . . . . . . . . . . . . 8-18

MARC Model 166-010. . . . . . . . . . . . . . . . . . . . . . . . . . 8-20

Radio Modem Configurations. . . . . . . . . . . . . . . . . . . . . . . 8-21

Configuring RSLinx Classic Software for DF1 Half-Duplex Communications

Table of Contents 7

DATA-LINC Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-23

SRM6000/6100/6200E. . . . . . . . . . . . . . . . . . . . . . . . . . 8-23

SRM6000/6100/6200E-SLC . . . . . . . . . . . . . . . . . . . . . . 8-25

SRM6000/6100/6200E-PLC . . . . . . . . . . . . . . . . . . . . . . 8-27

Electronic Systems

Technology (ESTeem) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-29

Microwave Data Systems (MDS). . . . . . . . . . . . . . . . . . . . . 8-35

MDS Model 2100 and 4100 Master Stations . . . . . . . . . . 8-36

MDS Model 2310 and 4310 Remote Stations . . . . . . . . . 8-37

MDS Model 9810 Spread Spectrum . . . . . . . . . . . . . . . . 8-38

Power Line Modem

Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-39

DATA-LINC Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-39

LCM100 Line Carrier Modem . . . . . . . . . . . . . . . . . . . . 8-39

Chapter 9

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1

Configuring RSLinx Classic Version 2.x as a Master Station . 9-1 Configuring RSLinx Classic Version 2.x as a Slave Station . . 9-10

Using Dial-up Telephone Communication

Remotely Program Allen-Bradley Processors Over a Telemetry Network

Chapter 10

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1

Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-2

Setting up the System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

Configure the Processor . . . . . . . . . . . . . . . . . . . . . . . . 10-3

Configure the Modems for the PLC-5, SLC, and Logix

Processors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3

Configure the Modems for MicroLogix 1100/1200/1500

Controllers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-4

Communicating Over the Telephone Line . . . . . . . . . . . . . 10-4

Initiate Modem Dialing. . . . . . . . . . . . . . . . . . . . . . . . . 10-5

Verify Connection to the Remote Modem . . . . . . . . . . . 10-6

Transfer Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7

Disconnect the Telephone Link . . . . . . . . . . . . . . . . . . 10-7

Peer-to-Peer Communication . . . . . . . . . . . . . . . . . . . . . . . 10-8

Report-by-Exception and/or

Master Station-Initiated Communication . . . . . . . . . . . . . . . 10-9

Chapter 11

Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1

Remote Programming via RSLinx® Gateway™ . . . . . . . . . . 11-2

Remote Programming via SLC 5/05 Ethernet to

DF1 Passthru . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-4

Remote Programming via Logix EtherNet/IP to DF1 Bridge. 11-7

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8 Table of Contents

Modem Cable Reference

Basic DF1 Protocol Troubleshooting

Appendix A

Appendix Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Enhanced PLC-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2

1747-KE Interface Module . . . . . . . . . . . . . . . . . . . . . . . . . A-3

ASCII Terminal to 1747-KE module . . . . . . . . . . . . . . . . . . A-4

SLC 5/03, 5/04, or 5/05, Logix, and MicroLogix 1500

Channel 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5

1785-KE Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-6

MicroLogix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-7

Appendix B

Appendix Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

General Tips. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Communication Troubleshooting . . . . . . . . . . . . . . . . . . . . B-1

DF1 Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3

DF1 Half-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . B-4

DF1 Full-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . B-6

DF1 Radio Modem Protocol. . . . . . . . . . . . . . . . . . . . . . . . B-7

Third-Party Supplier Contact Information

Worksheets

Appendix C

Appendix Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

Contact List. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

Appendix D

Appendix Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1

When You’re Finished. . . . . . . . . . . . . . . . . . . . . . . . . . . . D-2

How to Use the Worksheets . . . . . . . . . . . . . . . . . . . . . . . D-3

Worksheet 1.1 SCADA System Schematic . . . . . . . . . . . . . . D-4

Worksheet 2.1 Enhanced PLC-5 DF1 Half-Duplex Master

Station Configuration Using Standard Communication. . . . . D-5

Worksheet 2.2 Enhanced PLC-5 DF1 Half-Duplex Master Station Configuration Using Message-based Communication D-6 Worksheet 2.3 Enhanced PLC-5 DF1 Half-Duplex Slave

Station Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-7

Worksheet 2.4 Enhanced PLC-5 DF1 Full-Duplex

Point-to-Point Configuration . . . . . . . . . . . . . . . . . . . . . . . D-8

Worksheet 3.1 MicroLogix 1100/1200/1500 DF1 Half-Duplex Master Station Configuration Using Standard

Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-9

Worksheet 3.2 MicroLogix 1100/1200/1500 DF1 Half-Duplex Master Station Configuration Using Message-based

Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-10

Worksheet 3.3 MicroLogix 1100/1200/1500 DF1 Half-Duplex

Slave Station Configuration . . . . . . . . . . . . . . . . . . . . . . . D-11

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Table of Contents 9

Worksheet 3.4 MicroLogix 1100/1200/1500 DF1

Full-Duplex Point-to-Point Configuration . . . . . . . . . . . . . D-12

Worksheet 3.5 MicroLogix 1100/1200/1500 Radio Modem

Slave Station Configuration . . . . . . . . . . . . . . . . . . . . . . . D-13

Worksheet 4.1 SLC 5/03, 5/04, and 5/05 DF1 Half-Duplex Master Station Configuration Using Standard

Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-14

Worksheet 4.2 SLC 5/03, 5/04, and 5/05 DF1 Half-Duplex Master Station Configuration Using Message-based

Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-15

Worksheet 4.3 SLC 5/03, 5/04, and 5/05 DF1 Half-Duplex

Slave Station Configuration . . . . . . . . . . . . . . . . . . . . . . . D-16

Worksheet 4.4 SLC 5/03, 5/04, and 5/05 DF1 Full-Duplex

Point-to-Point Configuration . . . . . . . . . . . . . . . . . . . . . . D-17

Worksheet 4.5 SLC 5/03, 5/04, and 5/05 DF1 Radio

Modem Station Configuration . . . . . . . . . . . . . . . . . . . . . D-18

Worksheet 5.1 SLC 500 Processor with 1747-KE Module

DF1 Half-Duplex Slave Station Configuration . . . . . . . . . . D-19

Worksheet 5.2 SLC 500 Processor with 1747-KE Module

Point-to-Point Configuration . . . . . . . . . . . . . . . . . . . . . . D-20

Worksheet 6.1 MicroLogix 1000 DF1 Half-Duplex Slave

Station Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . D-21

Worksheet 7.1 Logix DF1 Half-Duplex Master Station

Configuration Using Standard Communication . . . . . . . . . D-22

Worksheet 7.2 Logix DF1 Half-Duplex Master Station

Configuration Using Message-based Communication . . . . D-23

Worksheet 7.3 Logix DF1 Half-Duplex Slave Station

Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-24

Worksheet 7.4 Logix DF1 Full-Duplex Point-to-Point

Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-25

Sample Ladder Logic

Appendix E

Appendix Objective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-1

SLC DF1 Half-Duplex Master Standard Mode,

Master-initiated MSG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-2

SLC DF1 Half-Duplex Master Message-based Mode and DF1

Radio Modem initiated MSG . . . . . . . . . . . . . . . . . . . . . . . E-4

SLC DF1 Half-Duplex Slave and DF1 Radio Modem

Report-by-Exception MSG . . . . . . . . . . . . . . . . . . . . . . . . . E-6

PLC-5 and MicroLogix 1100/1200/1500 DF1 Half-Duplex

Master Standard Mode, Master-initiated MSG . . . . . . . . . . . E-8

PLC-5 and MicroLogix 1100/1200/1500 DF1 Half-Duplex

Master Message-based, Master-initiated MSG . . . . . . . . . . E-10

PLC-5 and MicroLogix 1100/1200/1500 DF1 Half-Duplex

Slave Report-by-Exception MSG. . . . . . . . . . . . . . . . . . . . E-12

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10 Table of Contents

MicroLogix 1000 Analog DF1 Half-Duplex Slave

Report-by-Exception MSG . . . . . . . . . . . . . . . . . . . . . . . . E-14

Logix DF1 Half-Duplex Master Standard Mode,

Master-Initiated MSG . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-16

Logix DF1 Half-Duplex Master Message-based Mode,

Master-Initiated MSG . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-19

Logix DF1 Half-Duplex Slave Report-By-Exception MSG. . E-21

Glossary

Index

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Preface

What SCADA Information Is Available?

Audience

Two principle SCADA documents are available:

• SCADA System Application Guide Publication AG-UM008 (this

manual)

– Describes how to configure Allen-Bradley® products and

third-party modems

– Describes how to send messages – Provides application samples

• SCADA System Selection Guide (Publication AG-SG001)

– Presents Allen-Bradley capabilities for SCADA applications – Guides you through choosing SCADA system components

We designed this document for individuals who are configuring a SCADA system or are answering configuration questions. This document assumes you know how to:

• handle, install, and operate the products referenced in this

document

• install, navigate through, and use the software products

referenced in this document

• prepare cables, if necessary

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2 Preface

Contents of this Manual

Refer to the following listing for the contents of this user manual.

Chapter Title Contents

1 Designing

Communication

2 Configuring Enhanced

3 Configuring MicroLogix™

4 Configuring SLC™ 5/03,

5 Configuring SLC™ 500

6 Configuring MicroLogix

7 Configuring Logix

8 Configuring Modems Provides information on connecting

Processors

PLC-5

1100/1200/1500 Controllers

5/04, and 5/05 Processors

Processors with 1747-KE Interface Modules

1000 Controllers

Controllers

Design and configuration choices for getting information to and from slave stations.

Set up an enhanced PLC-5 processor as a master station, slave station, or a station on a point-to-point link.

Set up a MicroLogix 1100/1200/1500 controller as a master station, slave station, or a station on a point-to-point link.

Set up an SLC 5/03, 5/04, and 5/05 processor as a master station, slave station, or a station on a point-to-point link.

Set up an SLC 500 fixed or modular processor (SLC 5/01 or 5/02) with a 1747-KE as a remote station, or a station on a point-to-point link.

Set up a MicroLogix controller as a slave station, or a station on a point-to-point link.

Set up Logix controllers as a master station, slave station, or a station on a point-to-point link.

modems to Allen-Bradley devices.

10 Using Dial-up Telephone

11 Remotely Programming

A Modem Cable Reference Provides cable information. B Basic DF1 Protocol

C Third-Party Supplier

D Worksheets Provides worksheets to document your

E Sample Ladder Logic Provides information for developing your

Glossary

Configuring RSLinx® Classic Software for DF1 Half-Duplex Communications

Communication

Allen-Bradley Processors Over a Telemetry Network

Troubleshooting

Contact Information

Provides reference information needed while configuring RSLinx Classic communication server software as a DF1 half-duplex polling master station or as a DF1 half-duplex slave station.

Provides information on how to set up and initiate dial-up communication.

Provides information on how to set up and configure RSLogix programming terminals on Ethernet to program remote processors.

Provides information on how to troubleshoot communication errors.

Provides 3rd party vendor contact information.

serial channel configurations.

messaging logic.

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Preface 3

Terms

We use these terms frequently in this book:

Te rm Definition

Logix processor A collective name used to refer to ControlLogix™,

FlexLogix™, and CompactLogix™ processors.

Enhanced PLC-5 processor A collective name used to refer to PLC-5/11, -5/20,

-5/30, -5/40, -5/60, and PLC-5/80 processors.

Ethernet PLC-5 processor A collective name used to refer to PLC-5/20E,

-5/40E, and -5/80E processors.

master station A device (programmable controller with I/O modules

or a workstation) that sends data to and collects data from devices connected on a point-to-multipoint, half-duplex network.

slave station A device (programmable controller with I/O modules)

that is located in a remote site away from the master station and that controls I/O points at the remote site. A slave station accepts commands from and can send data (if capable) to a master station via a telemetry network.

See the Glossary for other definitions.

Address Conventions

Addresses

These values Are represented as

octal X decimal X

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4 Preface

Related Publications

The following documents contain additional information concerning Allen-Bradley programmable controller products. To obtain a copy, contact your local Allen-Bradley office or distributor:

Title Publication Number

Enhanced and Ethernet PLC-5 Programmable Controllers User Manual

PLC-5 Instruction Set Reference Manual 1785-RM001 SLC 500 Instruction Set Reference Manual 1747-RM001 SLC 500 Modular Hardware Style Manual 1747-UM0011 DH-485/RS232C Interface Module User Manual 1747-UM005 MicroLogix 1000 Programmable Controllers Users Manual 1761-UM003 ControlLogix System User Manual 1756-UM001 Logix5000™ Controllers Common Procedures Programming

Manual Logix Controllers General Instruction Set Reference

Manual MicroLogix 1200 and 1500 Instruction Set Reference

Manual MicroLogix 1200 User Manual 1762-UM001

1785-UM012

1756-PM001

1756-RM003

1762-RM001

MicroLogix 1500 User Manual 1764-UM001 CompactLogix System User Manual 1769-UM011 FlexLogix System User Manual 1794-UM001 DF1 Protocol and Command Set Reference Manual 1770-RM516 2004-2005 Americas Edition/Encompass Program Product

Designing Communication

Chapter

Chapter Objectives

Use this chapter along with the configuration chapters of the devices in your SCADA system to help you make design and configuration choices for getting information to and from slave stations.

While designing your communication scheme, consider these application requirements:

• responsiveness

• determinism

• cost

• efficiency

The factors that affect communication are a result of the protocol you are use, either half-duplex or full-duplex.

For information about See page

choosing a polling mode for the DF1 Half-Duplex protocol 1-2 designing a communication scheme using

standard-communication mode designing a communication scheme using message-based

communication mode

1-8

1-15

designing communication for DF1 Full-Duplex protocol 1-16 designing communication for DF1 Radio Modem protocol 1-17 what to do next 1-19

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1-2 Designing Communication

Choosing a Polling Mode for DF1 Half-Duplex Master

A master station can be configured to communicate with slave stations in either Message-based polling mode or Standard polling mode. The pros and cons of each polling mode are described below.

Message-Based Polling Mode

Message-based polling mode is best used in networks when communication with the slave stations is not time critical and where the user needs to be able to limit when and how often the master station communicates with each slave station. It is NOT recommended for systems that require time continuous communication between the master and all the slave stations have MSG instructions in their programs.

With Message-Based polling mode, the only time a master station communicates with a slave station is when a message (MSG) instruction in ladder logic is triggered to that particular slave station’s address. This polling mode gives the user complete control (through ladder logic) over when and how often to communicate with each slave station.

If multiple MSG instructions are triggered simultaneously, they will be executed in order, one at a time, to completion (i.e., the first MSG queued up will be transmitted and completed to done or error before the next queued up MSG is transmitted. Refer to appendix E for sample application programs). Any time a message is triggered to a slave station that can’t respond (for instance, if its modem fails), the message will go through retries and timeouts that will slow down the execution of all the other queued up messages. The minimum time to message to every responding slave station increases linearly with the number of slave stations that can’t respond.

If the Message-based selection is ‘don’t allow slaves to initiate messages,’ then even if a slave station triggers and queues up a MSG instruction in its ladder logic, the master station will not process it. This mode is similar to how a master/slave network based on Modbus protocol would work, since Modbus slave stations cannot ever initiate a message.

If the Message-based selection is ‘allow slaves to initiate messages,’ when a slave station initiates a message to the master station (polled report by exception messaging) or to another slave station (slave-to-slave messaging), the MSG command packet will remain in that slave station’s transmit queue until the master station triggers its own MSG command packet to it (which could be seconds, minutes or hours later, depending on the master’s ladder logic).

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Designing Communication 1-3

Standard Polling Mode

Standard polling mode is strongly recommended for larger systems that require time critical communication between the master and all the slave stations, or for any system where slave station-initiated messages are going to be used (this includes slave programming over the network, since this uses the same mechanism that slave-to-slave messaging uses). The Active Node Table automatically keeps track of which slaves are (and are not) communicating. Standard polling mode should NOT be used in cases where the user needs to be able to limit when and how often the master station communicates with each slave station.

Standard polling mode causes the master station to continuously send one or more 4-byte poll packets to each slave station address configured by the user in the poll list(s) in round robin fashion. As soon as the end of the polling list is reached, the master station immediately goes back and starts polling slave stations from the top of the polling list over again. This is independent and asynchronous to any MSG instructions that might be triggered in the master station ladder logic. In fact, this polling continues even while the master station is in program mode. Refer to chapter 3 of the DF1 Protocol and Command Set Reference Manual, publication 1770-RM516, for additional information.

When a MSG instruction is triggered while the master station is in run mode, the master station will transmit the message packet just after it finishes polling the current slave station in the poll list and before it starts polling the next slave station in the poll list (no matter where in the poll list it is currently at). If multiple MSG instructions have been triggered simultaneously, at least four message packets may be sent out between two slave station polls. Each of these messages will have an opportunity to complete when the master polls the slave station that was addressed in the message packet as it comes to it in the poll list.

If each of the transmitted message packets is addressed to a different slave station, the order of completion will be based upon which slave station address comes up next in the poll list, not the order that the MSG instructions were executed and transmitted in.

When a slave station receives a poll packet from the master station, if it has one or more message packets queued up to transmit (either replies to a command received earlier or MSG commands triggered locally in ladder logic), the slave station will transmit the first message packet in the transmit queue.

If the standard mode selection is ‘single message per poll scan,’ then the master station will then go to the next station in the poll list. If the standard mode selection is ‘multiple messages per poll scan,’ the

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1-4 Designing Communication

master station will continue to poll this slave station until its transmit queue is empty.

The master station knows the slave station has no message packets queued up to transmit when the slave station responds to the master poll packet with a 2-byte poll response.

Every time a slave station responds or doesn’t respond to its poll packet, the master station automatically updates its active node list (again, even if it’s in program mode). In this list, one bit is assigned to each possible slave station address (0 to 254). If a slave station doesn’t respond when it is polled, its active node list bit is cleared. If it does respond when it is polled, its active node bit is set. Besides being an excellent online troubleshooting tool, two common uses of the active node list are to report good/bad communication status for all slave stations to an operator interface connected to the master station for monitoring, alarming and logging purposes, and to precondition MSG instructions to each particular slave.

This second use is based on the supposition that if a slave station didn’t respond the last time it was polled (which was just a few seconds ago, if that long), then chances are it won’t be able to receive and respond to a MSG instruction now, and so it would most likely just end up going through the maximum number of retries and timeouts before completing in error (which slows down both the poll scan and any other messaging going on). Using this technique, the minimum time to message to every responding slave station actually decreases as the number of slave stations that can’t respond increases.

IMPORTANT

In order to remotely monitor and program the slave stations over the half-duplex network while the master station is configured for Standard polling mode, the programming computer DF1 slave driver (Rockwell Software RSLinx) station address must be included in the master station poll list.

About Polled Report-by-Exception

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Polled report-by-exception lets a slave station initiate data transfer to its master station, freeing the master station from having to constantly read blocks of data from each slave station to determine if any slave input or data changes have occurred. Instead, through user programming, the slave station monitors its own inputs for a change of state or data, which triggers a block of data to be written to the master station when the master station polls the slave.

Designing Communication 1-5

If your SCADA application is time-critical and any two or more of the following apply, then you can benefit from polled report-by-exception messaging:

• communication channel is slow (2400 bps or less)

• average number of words of data to monitor in each slave

station is greater than five

• number of slave stations is greater than ten

About Slave-to-Slave Messaging

Most SCADA half-duplex protocols do not allow one slave station to talk to another slave station, except through special application-specific code, which requires processing overhead in the master station. However, Allen-Bradley’s DF1 half-duplex protocol implements slave-to-slave communications as a feature of the protocol within the master station, without any additional application code or extra processing overhead. Refer to chapter 3 of the DF1 Protocol and Command Set Reference Manual, publication 1770-RM516, for additional information.

If one slave station has a message to send to another, it simply includes the destination slave station’s address in the message instruction’s destination field in place of the master station’s address when responding to a poll. The master station checks the destination station address in every packet header it receives from any slave station. If the address does not match its own station address, the entire message is forwarded back onto the telemetry network to the appropriate slave station, without any further processing.

IMPORTANT

Slave stations using 1747-KE interfaces can respond to slave-to-slave messages but cannot initiate slave-to-slave messages.

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1-6 Designing Communication

Addressing Tips

Each station on the network including the master station must have a unique address. The address range is 0 to 254

have a maximum of 254 address 255

(3778) is the broadcast address, which you cannot select

stations on a single telemetry network. Station

as a station’s individual address.

A remote programming terminal station address should be reserved, even if remote programming is not considered a requirement initially. This address will need to be periodically polled, even though it will remain on the inactive poll list unless a remote programming terminal is online.

SLC 500 and MicroLogix 1000 Processor Addressing Considerations

When an SLC 5/02 or MicroLogix 1000 slave station issues a

PLC

-2-type message to a PLC-5 master station, the message’s destination in the PLC-5 processor’s data table is an integer file with the file number equal to the SLC 500 or MicroLogix 1000 processor station address.

(3768), so you can

An address lower than 9 may interfere with a PLC-5 processor master station since files 0-8 are usually left in their default configuration; file 9 is often used by programmers for the I/O list. Station address 255

is the broadcast address. So, assign addresses between 10

TIP

For all other master station types, the SLC 5/02 or MicroLogix 1000 slave station can initiate a 500

-25410.

CPU-type message.

When using an SLC 5/03, 5/04, or 5/05 processor, or a MicroLogix 1100, 1200 or 1500 controller, as a master station, the poll list configuration consists of a contiguous block of addresses. Therefore, assign slave station addresses in a contiguous block in order to avoid polling for nonexistent slave stations.

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Designing Communication 1-7

SLC 500 Processors with a 1747-KE Module Addressing Considerations

Since you can have up to 254 devices on a half-duplex network and 32 devices on a DH-485 network, to allow 255 DH-485 nodes requires using a group number. This parameter defines the address group of the SLC 500 half-duplex address. Each address group can consist of 32 addresses.

The slave address of the SLC 500 processor is determined with the following formula: (32*G)+ Α, where G is the group number (0 to 7) and A is the DH-485 node address of the SLC 500 processor.

One station address within each group of size 32 must be reserved for any 1747-KE modules configured with that group number. A second address within each group should also be reserved for local DH-485 programming terminals. These 16 addresses (two per group) should never have to be polled by the master station.

ATTENTION

Do not use slave addresses contained within a KE group. When nodes are added to respective DH-485 networks, there is a possibility of duplicate nodes.

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1-8 Designing Communication

Communication Scheme Design Using Standard-Mode

Polling List

Stn 1 Stn 2

Stn 3

1. Master station polls a slave station for data.

2. If the slave station has data to send, then it sends a

data packet. If there is no data to send then it sends an end of transmission packet (DLE EOT).

Standard-communication mode for an Allen-Bradley master station uses centralized polling to gather data from slave stations. A master station using this communication technique asks (polls) individual slave stations if they have any information to send. All stations on the link ‘hear’ the master station’s requests, but only the slave station to which a request is addressed replies. PLC-5, Logix and RSLinx master stations poll slave stations based on an ordered list (polling list) configured by the system designer. SLC 500 and MicroLogix master stations poll slave stations sequentially in a range of addresses configured by the system designer.

Figure 1.1 shows how a slave

station gets polled and how it responds.

A master station polls the slave stations in the order the slave stations appear on the list. Slave stations send either a data packet or a packet indicating that the station has no data to send.

Figure 1.1 Slave Station Polling and Response

Master Station

Modem

Return Data Packet or DLE EOT to Master

Modem

slave station 1

Poll to slave

Modem

slave station 2

Modem

slave station 3

Polling List

Stn 1 Stn 2

Master Station

Stn 3

1. Master station polls the next slave station for data.

2. If the slave station has data to send, then it sends a

data packet. If there is no data to send then it sends an end of transmission packet (DLE EOT).

3. Master station continues to poll each slave station

in the polling list. When the end of the list is reached, the master station then moves back to the beginning of the list and starts the polling sequence over again.

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Modem

Return Data Packet or DLE EOT to Master

Modem

slave station 1

Modem

slave station 2

Poll to slave

Modem

slave station 3

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Designing Communication 1-9

When the master station is configured for standard-communication mode, you do not need to program any master-station message instructions to communicate with slave stations. Communication with slave stations occurs by the master station sending polling packets to slave stations. You only need message instructions when you want the master station to write data to or read data from a location within a slave station’s data table.

To help you understand See

standard-communication mode Figure 1.2 how a master station requests data Figure 1.3

Figure 1.2 Standard Communication Mode

• Check for and send

outgoing MSG

• Select next station

to poll

timeout received and station active and tries < or = ‘DF1 message retries’

MSG received and multiple mode

forward data to or return data from data table

timeout received and station inactive

• Send poll

• Start ACK timeout

• Wait for EOT or

MSG (or timeout)

timeout received and station active and tries > ‘DF1 message retries’ make

station inactive

EOT received indicating no MSG to send make station active

(if inactive)

MSG received and single poll mode forward data

to or return data from data table

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1-10 Designing Communication

Master data table

reply packet received return

data

Figure 1.3 How a Master Station Requests Data

• Ladder logic

triggers MSG

• Master driver

formats command packet

ACK timeout received and tries > ‘DF1 message retries’ return error

indication

• Send command

packet

• Start ACK timer

• Wait for ACK (or

timeout)

ACK timeout received and station active and tries < or = ‘DF1 message retries’

reply timeout received

return error indication

• Start reply timer

• Resume polling

• Wait for reply (or

timeout)

ACK received

To design a communication scheme using standard-communication mode, you must do the following:

• design a polling scheme

• plan for timing issues

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Designing Communication 1-11

Designing a Polling Scheme

Each master station in a SCADA application must have a polling scheme configured. To design a polling scheme, do the following:

• choose the type of scheme best suited for your application

• optimize your polling scheme to obtain the best efficiency

The master station you are using determines the type of polling choices you have; however, Allen-Bradley master stations offer similar choices, such as:

• normal and priority polling lists

• ability to poll a slave station:

– once per occurrence in the poll list (single) – until it has no more messages to send (multiple)

Choosing Normal or Priority Polling Lists

Slave stations listed in a priority poll list are polled more frequently than those listed in the normal poll list. Place the slave stations that you need information from more frequently in a priority poll list.

Within each poll list, slave stations are assigned a status, which is either active or inactive. A slave station becomes inactive when it does not respond to a master station’s poll packet after the configured number of retries.

If your master station is a Logix controller or PLC-5, you can use application logic to reorder the polling lists and priority while the application logic is executing.

Figure 1.4 and Figure 1.5 show how normal and priority lists relate to one another.

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1-12 Designing Communication

Figure 1.4 The master station scans slave stations in a set sequence.

1. Scans all stations in the active priority

2. Scans one station in the inactive priority

3. Scans stations in the active normal poll file

4. Scans one station in the inactive normal poll file

Active Priority

Inactive Priority

Active Normal

poll file.

based on the normal poll group size, which you specify during configuration. For example, if the group size were 3, then three stations would be polled in the normal file before the master continues to the next step in the sequence.

after all stations in the active normal list have been polled.

Figure 1.5 Here is how the polling sequence applies to an application.

Poll List STN1 STN7

Poll List STN2 STN6

Poll List STN3 STN4

Group size = 1

Active Priority Poll List

Master

Station

Inactive Priority Poll List

Active Normal Poll List

aa bb

Modem

Inactive Normal Poll List

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Polling Sequence: STN1 STN7 STN2 STN3

STN1 STN7 STN6 STN4 STN5

Inactive Normal

Beginning of new scan

Poll List

STN5

Modem

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Designing Communication 1-13

Choosing Single or Multiple Message Transfer

Depending on your application’s requirement, you can choose the number of messages you want to receive from a slave station during its turn.

If you want to receive Choose

only one message from a slave station per poll per a station’s turn.

Choose this method only if it is critical to keep the poll list scan time to a minimum.

single transfer

as many messages from the slave station as it has in its queue.

multiple transfer

Planning for Timing Issues

Two types of timing categories exist.

• Protocol timers, which specify how long a master station will

wait to ‘hear’ from a slave station.

• Request to send (RTS) timers, which you can use to make sure

the modem is ready to accept data or has passed on the data (does not apply when control line is configured for No Handshaking).

Set and adjust these timing values as necessary for your application. Set your RTS times based on the communication media and modem you are using.

Design Considerations

• Define a polling list type to use (normal or priority).

• Define a station list.

• Use Figure 1.6 to help understand how the MSGs are handled

using standard communication.

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1-14 Designing Communication

1. Polled station 1; ready to poll station 2.

2. MSG sent to station 3 (MSG was waiting in queue).

Polling List

Stn 1

Stn 2

Stn 3

Figure 1.6 Effect of MSGs on Logix, PLC-5, SLC 500, and MicroLogix Polling

Master Station

Modem

MSG to slave

3. Master station continues polling where it left off in the polling

sequence, e.g., station 2.

Polling List

Stn 1 Stn 2

Master Station

Stn 3

4. Master station polls station 3.

5. Station 3 replies with data.

Polling List

Stn 1

Stn 2

Master Station

Modem

Stn 3

Modem

slave station 1

Return Data Packet or DLE EOT to Master

Modem

slave station 1

Modem

slave station 2

Poll to slave

Modem

slave station 2

Return Data Packet to Master

Modem

slave station 3

Modem

slave station

Poll to slave

6. Master station returns to beginning of the poll list.

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Modem

slave station 1

Modem

slave station 2

Modem

slave

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station 3

Designing Communication 1-15

Communication Scheme Design Using Message-Based Mode

Master Station

3. Master station waits a user-defined time ‘Reply

Modem

Message Wait’ parameter before polling the station for a reply.

In message-based communication mode, the master station sends solicited messages (messages programmed via ladder logic) to a specific slave station when the master requires information. In this mode, the communication link is inactive until the master station has a message to send to a slave station.

Figure 1.7 explains the

communication sequence that occurs.

Figure 1.7 Message-Based Communication

1. Message (via MSG instruction) sent

to a specific slave station (eg., slave station 1).

2. Slave station receives message and

sends an acknowledgment back (ACK).

Modem

Slave Station 1

4. Slave station forms a reply message to the

master station’s enquiry.

Modem

Slave Station 2

5. Master station polls slave station for its reply.

6. Slave station sends its reply message.

7. Master station receives reply and sends an

acknowledgement back (ACK).

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1-16 Designing Communication

Designing Communication for DF1 Full-Duplex Protocol

Data table

reply packet received

return data

When designing communication using DF1 full-duplex protocol, you must configure timeout values and retry counts that control the communication between a transmitting station and a receiving station. Consider the type of link media you are using to help you determine the best values for the timer and counters. For example, you can expect a message being sent over a satellite link to take longer than one being sent over a telephone leased-line link.

Figure 1.8 shows the

communication sequence for DF1 full-duplex protocol.

Figure 1.8 Read or Write Requests via DF1 Full-Duplex

• Ladder logic

triggers MSG

• DF1 driver

formats command packet

NAK received and retries

NAK received and retries > ‘NAK retries’ or ACK timeout received and tries > ‘ENQ retries’ return

error indication

• Send command

packet

• Start ACK timer

• Wait for ACK

(or timeout)

< or = ‘NAK retries’ or ACK timeout received and tries < or = ‘ENQ retries’

send enquiry

reply timeout received

return error indication

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• Start reply

timer

• Wait for

reply (or timeout)

ACK received

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Designing Communication 1-17

Designing Communication for DF1 Radio Modem Protocol

When designing communication using DF1 Radio Modem protocol, you must consider the capabilities of both the controllers and radio modems. The DF1 Radio Modem protocol can only be used with contollers that support and are configured for this protocol.

Determining When to Use DF1 Radio Modem Protocol

If your radio modem can handle full-duplex data port buffering and radio transmission collision avoidance, you can use peer-to-peer message initiation capability in every node (i.e., the ladder logic in any node can trigger a MSG instruction to any other node at any time). For messaging between nodes that are outside of radio transmission/reception range of each other, you may use either the Store and Forward capability of the protocol or the repeater capability of the radios.

If your radio modem cannot handle full-duplex data port buffering and radio transmission collision avoidance, you can still use DF1 Radio Modem protocol in a Master/Slave configuration, with message initiation limited to a single master node. If you still require slave node message initiation, then you must use the DF1 Half-Duplex protocol.

The primary advantage of using DF1 Radio Modem protocol for radio modem networks is in the transmission efficiency. Each read/write transaction (command and reply) requires only one transmission by the initiator (to send the command) and one transmission by the responder (to return the reply) as illustrated in of transmissions is minimized, radio power is minimized, and throughput is maximized. In contrast, DF1 Half-Duplex protocol requires five transmissions for the DF1 Master to complete a read/write transaction with a DF1 Slave as illustrated in Figure 1.10 illustrates the DF1 Radio Modem protocol.

An efficiency trade-off exists in that the DF1 Radio Modem protocol does not provide immediate feedback (ACK) to the initiator to indicate that the responder successfully received the communications packet without error.

The Store and Forward capability of the DF1 Radio Modem protocol allows messages between nodes that are outside of radio transmission/reception range of each other to be routed through intermediary nodes that are within range. Each of the intermediary nodes needs a Store and Forward table. The configuration needs to indicate, based on the source and destination addresses in the message packet, which packets to receive (store) and then re-broadcast (forward). capability.

Figure 1.11 illustrates the Store and Forward

Figure 1.9. The number

Figure 1.7.

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1-18 Designing Communication

Station 2

Figure 1.9 DF1 Radio Communication

1. Message (via MSG instruction) sent to a specific

station (eg., station 1).

Modem

2. Station 1 sends its reply message.

Figure 1.10 Read or Write Requests via DF1 Radio Modem

Modem

Station 1

• Ladder logic

triggers MSG

• DF1 driver

formats command packet

Data table

reply packet received return data

reply timeout received

return error indication

• Send command

packet

• Start reply

timer

• Wait for reply

(or timeout)

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Designing Communication 1-19

Figure 1.11 Applying Store and Forward in DF1 Radio Modem Protocol

What to Do Next?

Node 1 No Bits

(DST=4, SRC=1)

Make sure you:

• choose the communication method best suited for your

• make initial configuration choices for the communication

• use this chapter as a reference as you configure the devices in

(2nd rebroadcast)

REPLY 1

CMD 1

Node 2

1, 3, 4

CMD 1

(1st rebroadcast)

application.

method you have chosen.

your SCADA system.

(1st rebroadcast)

REPLY 1

Node 3

1, 2, 4

CMD 1

(2nd rebroadcast)

REPLY 1

(DST=1, SRC=4)

Node 4

No Bits

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1-20 Designing Communication

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Chapter

Configuring Enhanced PLC-5 Processors

Chapter Objectives

Overview

This chapter helps you set up an Enhanced PLC-5 processor as a master station, as a slave station, or as a station on a point-to-point link.

For information about See page

an overview of the tasks required to configure a PLC-5 processor 2-1 installing the processor 2-2 configuring the processor as a DF1 half-duplex master station using

standard-communication mode configuring the processor as a DF1 half-duplex master station using

message-based communication mode configuring the processor as a slave station 2-15 configuring the processor as a station on a point-to-point link 2-20 the types of messages you can send from a PLC-5 processor to

another processor, how to configure the MSG instruction, and some configuration characteristics

To configure an Enhanced PLC-5 processor, perform these tasks:

2-3

2-11

2-23

1. Install the processor; connect the serial cable to channel 0.

2. Define the processor’s communication characteristics using your

PLC-5 programming software.

3. Install and configure the modem for communication with the

processor. Connect the modem to the processor’s serial channel.

1 Publication AG-UM008C-EN-P - February 2005

2-2 Configuring Enhanced PLC-5 Processors

Figure 2.1 Configuring and Enhanced PLC-5

Modem

PLC-5 programming software

41188

Installing the Processor

Before installing the processor, set the processor switch assemblies.

Define By setting switch assembly

DH+ and DF1 point-to-point station address S1 RS-232 as the electrical interface for the serial

port

For details about installing the processor, see the Enhanced PLC-5 Programmable Controllers Quick Start, publication 1785-QS012.

For cable pinouts, see Figure 2.2 or Appendix A-2.

Figure 2.2 Enhanced PLC-5 Serial Port Pin Assignments and S2 Settings.

25-pin male 25-pin 9-pin

C. GND 1 1 NC TXD.OUT 2 2 3 RXD.IN 3 3 2 RTS.OUT 4 4 7 CTS.IN 5 5 8 DSR.IN 6 6 6 SIG.GND 7 7 5 DCD.IN 8 8 1 DTR.OUT 20 20 4

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Configuring Enhanced PLC-5 Processors 2-3

Configuring a DF1 Half-Duplex Standard Mode Master Station

Toggle pushed toward TOP

OFF Toggle pushed

toward BOTTOM ON

o Specify:

RS-232C

Set Switches:

12345678910

ON ON ON OFF OFF ON ON OFF ON OFF

The DF1 Point-to-Point Station Address of the processor is the same as the DH+ address defined by S1.

Choose standard-communication mode if you want to query slave stations for information based upon user-configured polling lists. This mode is used most often in point-to-multipoint configurations because it allows polled report-by-exception (

page 1-4), slave-to-slave messaging (page 1-5) and slave programming over the telemetry network to be implemented. In addition, in this mode the master station maintains an active node table which allows an HMI or programming terminal to immediately identify which slave nodes can currently communicate and which nodes cannot.

ATTENTION

Connect only the pins shown in figure 2.2. Do not use a ribbon cable or one that connects to every 25-pin.

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2-4 Configuring Enhanced PLC-5 Processors

1. Double-click on the Channel

Configuration file to bring up the Edit Channel Properties interface.

2. On the Channel 0 tab, choose

System (Master) for your Communication Mode.

To configure the processor for a master station using standard communication, place the processor into program mode and follow the steps below using your RSLogix

™ 5 software:

3. Configure the Serial Port,

Options, and Polling parameters according to Table 2.1.

4.Configure Options parameters

according to Table 2.1.

5. Configure the Polling

parameters according to Table 2.1.

6. When all parameters are set,

click OK.

7. Create station lists (page 2-8).

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Configuring Enhanced PLC-5 Processors 2-5

Define the Communication Driver Characteristics

Use Table 2.1 to help you understand the communication parameters you need to specify on the Channel Configuration screen for standard-communication mode.

Use Worksheet 2.1 (page D-5) for an example configuration and to record your station’s configuration.

Table 2.1 Communication Parameters for a PLC-5 Master Station Using Standard-Communication Mode

RSLogix 5 Tab Parameter Selections

Channel 0 Diagnostic File Select an unused integer file to store channel status information. You must define a diagnostic

file in order to be able to view channel 0 status. See description of what is in this file.

See Table 2.2 on page 2-8 for a

Remote Mode Change

Mode Attention Character

System Mode Character

User Mode Character

Serial Port Baud Rate Select a communication rate that all devices in your system support. Configure all devices in

Bits Per Character Match the number of bits per character to the devices with which you are communicating.

Stop Bits Match the number of stop bits to the devices with which you are communicating.

Control Line This parameter defines the mode in which the master driver operates. Choose a method

Check enable remote mode change if you want to switch the configuration of the channel during runtime. Leave the parameter set at the default (unchecked) if you are not using this feature.

Select a character that will signal a remote mode change. Leave the parameter set at the default if you are not using remote mode change.

Select a character that will signal the channel to switch into system mode. Leave the parameter set at the default if you are not using remote mode change.

Select a character that will signal the channel to switch into user mode. Leave the parameter set at the default if you are not using remote mode change.

the system for the same communication rate.

appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If the master modem is full duplex and the slave modem is full-duplex, choose

FULL-DUPLEX MODEM.

• If all the modems in the system are half-duplex, choose HALF-DUPLEX MODEM

WITHOUT CONTINUOUS CARRIER.

Serial Port Error Detect With this selection, you choose how the processor checks the accuracy of each DF1 packet

transmission. BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security. Select an error detection method that all devices in your system support. When possible, choose CRC.

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2-6 Configuring Enhanced PLC-5 Processors

RSLogix 5 Tab Parameter Selections

Options Station Address Define the octal address of the processor on the DF1 half-duplex link. Each station on a link

must have a unique address. Choose an address between 0 and 376

Station address 3778 is the broadcast address, which you cannot select as a station’s individual address.

DF1 Retries Defines the number of times a master station retries either a message before the master

station declares the message undeliverable, or poll packet to an active station before the master station declares that station to now be inactive.

RTS Send Delay RTS send delay is the amount of time, in 20 millisecond increments, that elapses between the

assertion of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The Clear to Send (CTS) signal must be high for transmission to occur.

RTS Off Delay RTS off delay is the amount of time, in 20 millisecond increments, that elapses between the

end of the message transmission and the de-assertion of the RTS signal. This time delay is a buffer to make sure that the modem has transmitted the message but should normally be left at zero.

ACK Timeout Define the amount of time, in 20 millisecond increments, that you want the processor to wait

for an acknowledgment from a slave station to its transmitted message before the processor retries the message or the message errors out.

Reply Message Wait

Define the amount of time, in 20 millisecond increments, that the master station will wait after receiving an ACK (to a master-initiated message) before polling the slave station for a reply. Choose a time that is, at minimum, equal to the longest time that a slave station needs to format a reply packet. This is typically the maximum scan time of the slave station. Note: This field is only valid if the polling mode field is configured to be MESSAGE BASED.

MSG Application Timeout

Define the number of 30 second increments within which the reply message must be received before the error bit is set on the message. The timer starts when the ACK is received.

Polling Polling Mode If you want to receive:

• only one message from a slave station per its turn, choose STANDARD (SINGLE

MESSAGE TRANSFER PER NODE SCAN). Choose this method only if it is critical to keep the poll list scan time to a minimum.

• as many messages from a slave station as it has, choose STANDARD (MULTIPLE

MESSAGE TRANSFER PER NODE SCAN).

Master Message Transmit

If you want the master station to:

• send all of the master station-initiated MSG instructions to the slave stations before

polling the next slave station in the poll list, choose Between Station Polls. This method makes certain that master station-initiated messages are sent in a timely and regular manner (after every slave station poll).

• only send master station-initiated MSG instructions when the master’s station number

appears in the polling sequence, choose In Poll Sequence. With this method, sending master station-initiated messages are dependent upon where and how often the master station appears in the poll list. To achieve the same goal as the Between Station Polls method, the master-station’s address would have to appear after every slave-station’s address.

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RSLogix 5 Tab Parameter Selections

Configuring Enhanced PLC-5 Processors 2-7

Polling Normal Poll Node

File

Normal Poll Group Size

Priority Poll Node File

Active Station File Enter an unused binary file that will store the status of all the stations in your network

1. To display Channel Status,

double-click on Channel Status, which is located within Channel Configuration.

Enter an unused integer file that will store the addresses of the slave stations you want in the normal poll list.

Enter the quantity of active stations located in the normal poll list that you want polled during a scan through the normal poll list before returning to the priority poll list.

Enter an unused integer file that will store the addresses of the slave stations you want in the priority poll list.

configuration. The file stores one station address per bit. 0 = inactive; 1 = active.

Displaying System (Master) Channel Status

2. To access the various channels

from the Channel Status screen, click on the tabs. Descriptions of the status screen fields can be found in Table 2.2.

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2-8 Configuring Enhanced PLC-5 Processors

Table 2.2 Descriptions of System Mode DF1 Master Channel Status Fields

Status Field Location Description

Clear Clear counters for all channels by clicking on Clear button. DCD Recover word 11 Displays the number of times the processor detects the DCD handshaking line has

gone low to high. Lost Modem word 12 Displays the number of times that the modem lost bit (S:17/5) has gone low to high. Messages Sent word 1 Displays the number of messages sent by the processor (including message retry). Messages Received word 2 Displays the number of messages the processor received with no error. Undeliverable Messages word 3 Displays the number of messages that were sent by the processor but not received

by the destination device. Messages Retry word 4 Displays the number of messages resent. Duplicate Messages Received word 9 Displays the number of times the processor received a message packet identical to

the previous message packet. EOT Received on First Poll word 8 Displays the number of times the Master received an EOT in response to the first

poll of a station. Bad Packet / No ACK word 7 Displays the number of incorrect data packets that the processor has received. Last Normal Poll List Scan (100 ms) word 5 The time it took to complete the previous scan of the normal station poll list. Max Normal Poll List Scan (100 ms) word 6 The maximum time taken to complete a scan of the normal station poll list. Last Priority Poll List Scan (100 ms) word 10 The time it took to complete the previous scan of the priority station poll list. Max Priority Poll List Scan (100 ms) word 13 The maximum time taken to complete a scan of the priority station poll list. DTR (Data Terminal Read) word 0; bit 4 Displays the status of the DTR handshaking line (asserted by the processor). DCD (Data Carrier Detect) word 0; bit 3 Displays the status of the DCD handshaking line (received by the processor). DSR (Data Set Ready) word 0; bit 2 Displays the status of the DSR handshaking line (received by the processor). RTS (Request to Send) word 0; bit 1 Displays the status of the RTS handshaking line (asserted by the processor). CTS (Clear to Send) word 0; bit 0 Displays the status of the CTS handshaking line (received by the processor).

Create Station Lists

After defining your polling files and group size, create station lists by entering the station address of each slave station into either the normal poll file or priority poll file of the PLC-5 data table. Place each station address in an individual word in a poll file (normal and priority) starting at word 2.

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Configuring Enhanced PLC-5 Processors 2-9

The normal and priority poll file layout is as follows:

This word in a poll file Contains this information

word 0 total number of stations to be polled (for a list) word 1 the address location (poll offset) of the station currently

being polled (as long as all configured stations are active) For example: a value of 1 means the station address stored in word 2 is being polled, 2 means the address stored in word 3 is being polled, etc. This word is automatically updated by the master station as a new slave station is polled.

word 2 through word xx the slave station address in the order that the stations

should be polled Store one station address in each word.

To place a station address in a poll file:

1. Access the PLC-5 data table.

2. Specify the address of the integer file that is either the normal

poll file or priority poll file (e.g., If the normal poll file is N11, then you specify N11:0).

3. Enter the station addresses of the slave stations you want in the

poll list starting at word 2. Put them in the order you want them polled.

IMPORTANT

PLC-5 station addresses are octal addresses. The poll files are integer files that default to a decimal radix. To properly enter PLC-5 station addresses in a poll file, you must either:

• change the radix of the file to octal

• convert the PLC-5 octal station addresses to

decimal

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2-10 Configuring Enhanced PLC-5 Processors

total number of stations

pointer showing the station address being polled

Figure 2.3 is an example of a station list containing three stations: octal addresses 10, 3, and 12. Station 12 is being polled.

Figure 2.3 Example Station List

address of first station in list

address of second station in list

address of third station in list

Monitor Active Stations

To see what stations are active, view the active station file. Each bit in the file represents a station on the link. The stations are numbered in order as a continuous bit-stream file starting with the first bit in the first word (

Figure 2.4 Example Active Station File

Address 15 Data 0

B11:0 1111 1111 1111 1111 Remote station 0 B11:1 1111 1111 1111 1111 Remote station 16 B11:2 1111 1111 1111 1111

Figure 2.4).

For PLC-5 processors:

Starting with these PLC-5 firmware revisions

Series E/Revision B Series D/Revision C Series C/Revision L Series B/Revision M Series A/Revision M

For all prior firmware revisions At power-up or after reconfiguration, the master

This is what you will see

At power-up or after reconfiguration, the master station assumes that all slave stations are inactive (bit=0).

station assumes that all slave stations are active (bit=1) and the station displays inactive only after it fails to respond to a poll packet.

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Configuring Enhanced PLC-5 Processors 2-11

Configuring a DF1 Half-Duplex Message-based Mode Master Station

Choose message-based communication mode if you want to use MSG instructions in user programming to communicate with one station at a time. If your application uses satellite transmission or public switched telephone network transmission, consider choosing message-based. Communication to a slave station can be initiated on an as-needed basis.

Also choose message-based mode when a redundant PLC-5 system is being used as a master station. Connect both PLC-5 processor serial ports to the master station modem through an RS-232 modem splitter and precondition all MSG instructions with the Primary Processor status bit.

With message-based mode, you do not have an active station file that you can use to monitor station status. Also, you cannot implement slave-to-slave messaging or slave programming over the telemetry network.

To configure the processor for a master station using message-based communication, place the processor in program mode and follow the steps below using RSLogix 5:

1. Double-click on the Channel

Configuration file to bring up the Edit Channel Properties interface.

2. On the Channel 0 tab, choose

System (Master) for your Communication Mode.

3. Configure the Serial Port,

Options, and Polling parameters according to Table 2.3.

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2-12 Configuring Enhanced PLC-5 Processors

4.Configure Options parameters

according to Table 2.3.

5. Configure the Polling

parameters according to Table 2.3.

6. When all parameters are set,

click OK.

Use Table 2.3 to help you understand the communication parameters you need to specify on the Edit Channel Properties screen.

Use Worksheet 2.2 (page D-6) for an example configuration and to record your station’s configuration.

Table 2.3 Communication Parameters for a PLC-5 Master Station Using Message-Based Communication Mode

RSLogix 5 Tab Parameter Selections

Channel 0 Diagnostic File Select an unused integer file to store channel status information. You must define a

diagnostic file in order to be able to view channel 0 status. description of what’s in this file.

Remote Mode Change Check enable remote mode change if you want to switch the configuration of the channel

during runtime. Leave the parameter set at the default (unchecked) if you are not using this feature.

Mode Attention Character

Select a character that will signal a remote mode change. Leave the parameter set at the default if you are not using remote mode change.

System Mode Character Select a character that will signal the channel to switch into system mode. Leave the

parameter set at the default if you are not using remote mode change.

User Mode Character Select a character that will signal the channel to switch into user mode. Leave the

parameter set at the default if you are not using remote mode change.

Serial Port Baud Rate Select a communication rate that all devices in your system support. Configure all

devices in the system for the same communication rate.

Bits Per Character Match the numbers of bits per character to the devices with which you are

communicating.

Stop Bits Match the number of stop bits to the devices with which you are communicating.

See Table 2.2 on page 2-8 for

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Configuring Enhanced PLC-5 Processors 2-13

RSLogix 5 Tab Parameter Selections

Serial Port Control Line This parameter defines the mode in which the master driver operates. Choose a method

appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If the master modem is full duplex and the slave modem is full-duplex, choose

FULL-DUPLEX MODEM.

• If all the modems in the system are half-duplex, choose HALF-DUPLEX MODEM

WITHOUT CONTINUOUS CARRIER.

Parity Parity provides additional message packet error detection. To implement even parity

checking, choose Even. To implement no parity checking, choose None.

Error Detect With this selection, you choose how the processor checks the accuracy of each DF1

packet transmission. BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security. Select an error detection method that all devices in your system support. When possible, choose CRC.

Options Station Address Define the octal address of the processor on the DF1 half-duplex link. Each station on a

link must have a unique address. Choose an address between 0 and 376

Station address 3778 is the broadcast address, which you cannot select as a station’s individual address.

DF1 Retries Define the number of times a master station retries either a message before the master

station declares the message undeliverable, or a poll packet to an active station before the master station declares the station to be inactive.

RTS Send Delay RTS send delay is the amount of time, in 20 millisecond increments, that elapses

between the assertion of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The Clear to Send (CTS) signal must be high for transmission to occur.

RTS Off Delay RTS off delay is the amount of time, in 20 millisecond increments, that elapses between

the end of the message transmission and the de-assertion of the RTS signal. This time delay is a buffer to ensure that the modem has transmitted the message but should normally be left at zero.

ACK Timeout Define the amount of time, in 20 millisecond increments, that you want the processor to

wait for an acknowledgment from a slave station to its transmitted message before retrying. This timeout value is also used for the poll response timeout.

Reply Message Wait Define the amount of time, in 20 millisecond increments, that the master station will wait

after receiving an ACK (to a master-initiated message) before polling the slave station for a reply. Choose a time that is, at minimum, equal to the longest time that a slave station needs to format a reply packet. This is typically the maximum scan time of the slave station.

MSG Application Timeout

The application timeout of the message is the number of 30 second increments within which the reply message must be received before the error bit is set on the message. The timer starts when the ACK is received.

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RSLogix 5 Tab Parameter Selections

Polling Polling Mode If you want to:

• accept unsolicited messages from slave stations, choose MESSAGE BASED

(ALLOW SLAVE TO INITIATE MESSAGES). Slave station-initiated messages are acknowledged and processed after all master station-initiated (solicited) messages. Note: Slave stations can only send messages when they are polled. If the message-based master station never sends a slave station a message, the master station will never send the slave station a poll. Therefore, to regularly obtain a slave station-initiated message from a slave station, you should choose to use standard communications mode instead.

• ignore unsolicited messages from slave stations, choose MESSAGE BASED

(DO NOT ALLOW SLAVES TO INITIATE MESSAGES). Slave station-initiated messages are acknowledged and discarded. The master station acknowledges the slave station-initiated message so that the slave station removes the message from its transmit queue, which allows the next packet slated for transmission into the transmit queue.

Master Message Transmit

If you want the master station to:

• send all of the master station initiated MSG instructions to the remote stations

before polling the next remote station in the poll list, choose Between Station Polls. This method makes certain that master station initiated messages are sent in a timely and regular manner (after every remote station poll).

• send only master station initiated MSG instructions when the master’s station

number appears in the polling sequence, choose In Poll Sequence. With this method, sending master station initiated messages are dependent on where and how often the master station appears in the poll list. To achieve the same goal as Between Station Polls method, the master station’s address would need to appear after every remote station’s address.

Normal Poll Node File Enter an unused integer file that will store addresses of the remote stations you want in

the normal poll list.

Active Station File Enter an unused binary file that will store the status of all the stations in your network

configuration. The file stores one address per bit. 0=inactive, 1=active.

Priority Poll Node File Enter an unused integer file that will store the addresses of the remote stations you want

in the priority poll list.

Normal Poll Group Size Enter the quantity of active stations located in the normal poll list that you want polled

during a scan through the normal poll list before returning to the priority poll list.

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Configuring Enhanced PLC-5 Processors 2-15

Configuring the Processor as a Slave Station

1. Double-click on the Channel

Configuration file to bring up the Edit Channel Properties interface.

2. On the Channel 0 tab, choose

System (Slave) for your Communication Mode.

To configure the processor as a slave station, place the processor in program mode and follow the steps below using your programming software:

3. Configure the Serial Port

parameters according to Table 2.4.

4.Configure the Options

parameters according to Table 2.4.

5. When all parameters are set,

click OK.

Use Table 2.4. to help you understand the communication parameters you need to specify on the Channel Configuration screen.

Use Worksheet 2.3 (page D-7) for an example configuration and to record your station’s configuration.

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2-16 Configuring Enhanced PLC-5 Processors

Table 2.4 Communication Parameters for a PLC-5 Slave Station.

RSLogix 5 Tab Parameter Selections

Channel 0 Diagnostic File Select an unused integer file to store channel status information. You must define a

diagnostic file in order to be able to view channel 0 status.

See Table 2.5 on

page 2-18 for a description of what this file contains.

Remote Mode Change Enable

Check enable remote mode change if you want to switch the configuration of the channel during runtime. Leave the parameter set at the default (unchecked) if you are not using this feature.

Mode Attention Character Select a character that will signal a remote mode change. Leave the parameter set

at the default if you are not using remote mode change.

System Mode Character Select a character that will signal the channel to switch into system mode. Leave

the parameter set at the default (unchecked) if you are not using remote mode change.

User Mode Character Select a character that will signal the channel to switch into user mode. Leave the

parameter set at the default if you are not using remote mode change.

Serial Port Baud Rate Select a communication rate that all devices in your system support. Configure all

devices in the system for the same communication rate.

Bits Per Character Match the number of bits per character to the devices with which you are

communicating. Stop Bits Match the number of stop bits to the devices with which you are communicating. Control Line This parameter defines the mode in which the slave station driver operates. Choose

a method appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If the master modem is full duplex and transmits a constant carrier and the

slave modem is half-duplex, choose HALF-DUPLEX MODEM WITH CONTINUOUS CARRIER.

• If all the modems in the system are half-duplex, choose HALF-DUPLEX

MODEM WITHOUT CONTINUOUS CARRIER.

Parity Parity provides additional message packet error detection. To implement even parity

checking, choose Even. To implement no parity checking, choose None.

Serial Port Error Detect With this selection, you choose how the processor checks the accuracy of each DF1

packet transmission.

BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security.

Select an error detection method that all devices in your system support.

When possible, choose CRC.

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Configuring Enhanced PLC-5 Processors 2-17

RSLogix 5 Tab Parameter Selections

Options Station Address Define the octal address of the processor on the DF1 half-duplex link. Each station

on a link must have a unique address. Choose an address between 0 and 376

Station address 3778 is the broadcast address, which you cannot select as a station’s individual address.

DF1 Retries The number of times a slave station retries a message before the slave station

declares the message undeliverable.

RTS Send Delay RTS send delay is the amount of time, in 20 millisecond increments, that elapses

between the assertion of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The CTS (Clear-to-Send) signal must be high for transmission to occur.

RTS Off Delay RTS off delay is the amount of time, in 20 millisecond increments, that elapses

between the end of the message transmission and the de-assertion of the RTS signal. This time delay is a buffer to make sure that the modem has transmitted the message but should normally be left at zero.

ACK Timeout Define the amount of time, in 20 millisecond increments, that you want the

processor to wait for an acknowledgment from the master station to its transmitted message.

Detect Duplicate Messages Duplicate packet detection lets the PLC-5 processor detect if it has received a

message that is a duplicate of its most recent message from the master station. If you choose detect duplicate messages, the processor will acknowledge (ACK) the message but will not act on it since it has already performed the message’s task when it received the command from the first message. If you want to detect duplicate packets and discard them, check this parameter. If you want to accept duplicate packets and execute them, leave this parameter unchecked.

MSG Application Timeout Define the number of 30 second increments within which the reply message must be

received before the error bit is set on the message. The timer starts when the ACK is received.

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1. To display Channel Status,

double click on Channel Status, which is located within Channel Configuration.

2. To access the various channels

from the Channel Status Screen, click on the tabs. Descriptions of the status screen fields can be found in Table 2.5.

Displaying Slave System Channel Status

Table 2.5 Descriptions of System Mode DF1 Slave Channel Status Fields

Status Field Diagnostic File Location Definition

DCD Recover word 11 The number of times the processor detects the DCD handshaking line

has gone low to high

Messages Sent word 1 The total number of DF1 messages sent by the processor (including

message retries)

Messages Received word 2 The number of messages received with no errors

Polling Received word 6 The number of master poll packets received by the processor

Received NAK word 5 The number of NAKs received by the processor

Lack of Memory/No ACK Sent

word 8 The number of times the processor could not receive a message

because it did not have available memory

Lost Modem word 12 The number of times the lost modem bit has gone low to high

Messages Retry word 4 The number of message retries sent by the processor

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Configuring Enhanced PLC-5 Processors 2-19

Status Field Diagnostic File Location Definition

Undelivered Messages word 3 The number of messages that were sent by the processor but not

acknowledged by the destination device

Duplicate Messages Received

word 9 The number of times the processor received a message packet identical

to the previous message packet

Bad Packet/No ACK word 7 The number of incorrect data packets received by the processor for

which a no ACK was returned

DTR (Data Terminal Ready) word 0;bit 4 The status of the DTR handshaking line (asserted by the processor)

DSR (Data Set Ready) word 0;bit 2 The status of the DSR handshaking line (received by the processor)

RTS (Request to Send) word 0;bit 1 The status of the RTS handshaking line (asserted by the processor)

CTS (Clear to Send) word 0;bit 0 The status of the CTS handshaking line (received by the processor)

DCD (Carrier Detect) word 0;bit 3 The status of the DCD handshaking line (received by the processor)

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2-20 Configuring Enhanced PLC-5 Processors

Configuring the Processor as a Station on a Point-to-Point Link

1. Double-click on the Channel

Configuration file to bring up the Edit Channel Properties interface.

2. On the Channel 0 tab, choose

System (Point-to-Point) for your Communication Mode.

To configure the processor as a station on a point-to-point link, place the processor in program mode and follow the steps below using your programming software:

3. Configure the Serial Port

parameters according to Table 2.6.

4.Configure the Options

parameters according to Table 2.6.

5. When all parameters are set,

click OK.

Use Table 2.6. to help you understand the screen parameters you need to specify on the Channel Configuration screen.

Use Worksheet 2.4 (page D-8) for an example configuration and to record your station’s configuration.

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Configuring Enhanced PLC-5 Processors 2-21

Table 2.6 Configuring the PLC-5 Processor as a Device on a Point-to-Point Link

RSLogix 5 Tab Parameter Selections

Channel 0 Diagnostic File Select an unused integer file that you want to use to store channel status information. You

must define a diagnostic file in order to be able to view channel 0 status.

See Table 2.7 on

page 2-22 for a description of what this file contains.

Remote Mode Change Enable remote mode change if you want to switch the configuration of the channel during

runtime. Leave the parameter set at the default if you are not using remote mode change.

Mode Attention Character

Select a character that will signal a remote mode change. Leave the parameter set at the default if you are not using remote mode change.

System Mode Character Select a character that will signal the channel to switch into system mode. Leave the

parameter set at the default if you are not using remote mode change.

User Mode Character Select a character that will signal the channel to switch into user mode. Leave the

parameter set at the default if you are not using remote mode change.

Serial Port Baud Rate Select a communication rate that all devices in your system support. Configure all devices

in the system for the same communication rate. Bits Per Character Match the number of bits per character to the device with which you are communicating. Stop Bits Match the number of stop bits to the device with which you are communicating. Control Line This parameter defines the mode in which the driver operates. Choose a method

appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If you are using a full-duplex modem, choose FULL-DUPLEX.

Parity Parity provides additional message packet error detection. To implement even parity

checking, choose Even. To implement no parity checking, choose None.

Options NAK Receive Define the number of NAKs the processor can receive in response to a transmitted message

before the station declares the message undeliverable. DF1 ENQs Define the number of enquiries (ENQs) that you want the processor to send after an ACK

timeout occurs before the station declares the message undeliverable. ACK Timeout Define the amount of time, in 20 millisecond increments, you want the processor to wait for

an acknowledgment from a station to its transmitted message.

Options Detect Duplicate

Messages

Duplicate Packet Detection lets the PLC-5 processor detect if it has received a message that

is a duplicate of its most recent message from another station. If you choose detect

duplicate messages, the processor will acknowledge (ACK) the message but will not act on

it since it has already performed the message’s task when it received the command from

the first message.

If you want to detect duplicate packets and discard them, check this parameter. If you want

to accept duplicate packets, and execute them, leave this parameter unchecked. MSG Application

Timeout

Define the number of 30 second increments within which the reply message must be

received before the error bit is set on the message. The timer starts when the ladder

program first initiates the message and is restarted if/when the ACK is received. Error Detect With this selection you choose how the processor checks the accuracy of each DF1 packet

transmission.

BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security.

Select an error detection method that all devices in your system support.

When possible, choose CRC.

Important: The station address in the point-to-point driver is determined by the DH+ address defined by switch assembly S1.

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1. To display Channel Status,

double-click on Channel Status, which is located within Channel Configuration.

2. To access the various channels

from the Channel Status screen, click on the tabs. Descriptions of the status screen fields can be found in Table 2.7.

Displaying Point-to-Point System Channel Status

Table 2.7 Descriptions of System (Point-to-Point) Channel Status Fields

Status Field Diagnostic File Location Definition

DCD Recover word 11 The number of times the processor detects the DCD handshaking line has

gone low to high

Messages Sent word 1 The total number of DF1 messages sent by the processor (including

message retries) Messages Received word 2 The number of messages received with no errors Inquiry Received word 6 The number of master poll packets received by the processor Received NAK word 5 The number of NAKs received by the processor Lack of Memory/Sent NAK word 8 The number of times the processor could not receive a message because

it did not have available memory Lost Modem word 12 The number of times the lost modem bit has gone low to high Undelivered Messages word 3 The number of messages that were sent by the processor but not

acknowledged by the destination device Duplicate Messages

Received

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word 9 The number of times the processor received a message packet identical

to the previous message packet

Configuring Enhanced PLC-5 Processors 2-23

Status Field Diagnostic File Location Definition

Inquiry Sent word 4 The number of ENQs sent by the processor Bad Packet/No ACK word 7 The number of incorrect data packets received by the processor for which

a NAK was returned DTR (Data Terminal Ready) word 0;bit 4 The status of the DTR handshaking line (asserted by the processor) DSR (Data Set Ready) word 0;bit 2 The status of the DSR handshaking line (received by the processor) RTS (Request to Send) word 0;bit 1 The status of the RTS handshaking line (asserted by the processor) CTS (Clear to Send) word 0;bit 0 The status of the CTS handshaking line (received by the processor) DCD (Carrier Detect) word 0;bit 3 The status of the DCD handshaking line (received by the processor)

Messaging

Messaging can occur between:

• a master station and a slave station

• a slave station and its master station

(See Polled Report-by-Exception)

• slave stations or between two processors connected via a

point-to-point link

Master Station to Slave Station

A PLC-5 master station communicates with the slave stations that are connected to it via modems in a point-to-multipoint configuration. A master station sends a slave station messages to receive status or issue commands. For sample messaging ladder logic, see page

E-8.

Polled Report-by-Exception

Slave stations can gather information from the I/O points they are responsible for and can send any anomalous readings to the master station. To do this, write ladder logic in the slave station to monitor certain conditions and send the data in a MSG instruction to the master station. block that a PLC-5 processor in a slave station can send to a PLC-5 master station. For sample messaging ladder logic when using a PLC-5 as a slave, see page

Figure 2.6 is an example MSG instruction and control

E-12.

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2-24 Configuring Enhanced PLC-5 Processors

Processor-to-Processor

A processor-to-processor message can be two types:

• In a point-to-multipoint configuration, the messaging would be

between slave stations; the master station automatically routes the message.

Master Station

MSG from Slave Station 1 to Slave Station 2

Modem

Slave Station 1

Master Station routes MSG to Slave Station 2

Modem

Slave Station 2

• In a point-to-point configuration, the messaging would be

between the two connected peer devices.

MSG

Modem

Station 1

Modem

Station 2

The configuration of the network (point-to-multipoint vs. point-to-point) and the configuration of the station (master, slave, or peer) does not affect how you configure a MSG instruction. That is, a MSG instruction being sent between two PLC-5 slave stations is configured the same as a MSG instruction between two PLC-5 processors connected point-to-point, which is configured the same as a MSG instruction between a PLC-5 master station and a PLC-5 slave station. See

Figure 2.5 through Figure 2.8 for example MSG control

blocks.

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Configuring Enhanced PLC-5 Processors 2-25

Considerations When Configuring MSG Control Blocks

Keep these considerations in mind when configuring messages between a PLC-5 and SLC 500 or MicroLogix processor.

The following table lists which PLC-5 processors (series and revision) you can use with the MSG instruction to transfer data from/to a PLC-5 processor to/from any SLC 500 processor or MicroLogix 1000 in SLC native mode.

Processor Series/Revision

Series A / revision M PLC-5/40, -5/40L, -5,60, -5/60L Series A / revision J PLC-5/30 Series A / revision H PLC-5/11, -5/20 Series B / revision J PLC-5/40, -5/40L, -5/60, -5/60L Series C / revision G PLC-5/11, -5/20, -5/20E, -5/30, -5/40, -5/40L, -5/V40,

Series D / all PLC-5/11, -5/20, -5/20E, -5/30, -5/40, -5/40L, -5/V40,

Series E / all PLC-5/11, -5/20, -5/20E, -5/30, -5/40, -5/40L, -5/V40,

Processors

-5/V40L, -5/40E, -5/60, -5/60L, -5/80, -5/80E, -5/V80,

-5/20C, -5/40C, -5/80C

-5/V40L, -5/40E, -5/60, -5/60L, -5/80, -5/80E, -5/V80,

-5/20C, -5/40C, -5/80C

-5/V40L, -5/40E, -5/60, -5/60L, -5/80, -5/80E, -5/V80,

-5/20C, -5/40C, -5/80C

• Since all SLC 5/05, 5/04 and 5/03 processors with Operating

System 301 or higher can respond to (and initiate) PLC-5 native mode message commands, all PLC-5 processors can transfer data between their data tables and the data table of these particular SLC processors (except for the I/O image table) as if they were messaging with another PLC-5 processor.

• In a single instruction, the maximum amount of words you can

read from or write to through channel 0 is as follows:

– SLC 500, 5/01, 5/02, and MicroLogix 1000 processor, 41 words – SLC 5/03, 5/04, 5/05, MicroLogix 1100/1200/1500 processor,

103 words

When configuring messages between a PLC-5 and Logix processor, use the PLC-5 typed read and write commands and enclose the name of the Logix tag in double quotes. This is called logical ASCII addressing.

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2-26 Configuring Enhanced PLC-5 Processors

Example MSG Control Blocks

Application See Page

PLC-5 read message to another PLC-5 processor Figure 2.5 2-26 PLC-5 write message to another PLC-5 processor Figure 2.6 2-27

Ladder Rung

Control Block

PLC-5 read message to an SLC 500 or MicroLogix 1000

Figure 2.7 2-28

processor PLC-5 write message to an SLC 500 or MicroLogix 1000

Figure 2.8 2-29

processor

Figure 2.5 Example of a PLC-5 read MSG to Another PLC-5 (or SLC 5/03, 5/04, 5/05, MicroLogix 1100/1200/1500, or Logix) processor

MSG being sent to another PLC-5 processor.

MSG being sent out channel 0 (must use MG file type).

If the destination were a Logix processor, then the address could also be entered as ’tagname’.

Publication AG-UM008C-EN-P - February 2005

This MSG example tells this (master) PLC-5 to read the information from PLC-5 (slave) station 13

’s, location N7:0 and place the

information in file N19:0 (master).

Ladder Rung

Control Block

Configuring Enhanced PLC-5 Processors 2-27

Figure 2.6 Example of a PLC-5 Write MSG to Another PLC-5 (or SLC 5/03, 5/04, 5/05, MicroLogix 1100/1200/1500, or Logix) Processor

MSG being sent to another PLC-5 processor.

MSG being sent out channel 0 (must use MG file type).

If the destination were a Logix processor, then the address could also be entered as “tagname”.

This MSG example tells this (master) PLC-5 to write the information from its file N19:0 through its serial port (channel 0) to the PLC-5 (slave) station 13

. The data’s destination is N7:0 of the PLC-5 (slave)

station.

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2-28 Configuring Enhanced PLC-5 Processors

Ladder Rung

Control Block

Figure 2.7 Example of a PLC-5 Read MSG to an SLC 500 or MicroLogix Processor

MSG being sent to an SLC 500 or MicroLogix processor.

MSG being sent out channel 0 (must use MG file type).

This MSG example tells this PLC-5 (master) to read the information from SLC 500 (slave) 13

(158) S:1 and place the information in its

N15:0 file.

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Ladder Rung

Control Block

MSG being sent to an SLC 500 or MicroLogix processor.

Configuring Enhanced PLC-5 Processors 2-29

Figure 2.8 Example of a PLC-5 Write MSG to an SLC 500 or MicroLogix Processor

MSG being sent out channel 0 (must use MG file type).

This MSG example tells the PLC-5 master station to write the information from its N15:1 through its serial port (channel 0) to the SLC 500 slave station 13

(158). The data’s destination is N7:0 of the

SLC 500 slave station.

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2-30 Configuring Enhanced PLC-5 Processors

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Chapter

Configuring MicroLogix 1100/1200/1500 Controllers

Chapter Objectives

This chapter helps you set up a MicroLogix 1100, 1200, or 1500 controller as a master station, as a slave station, as a radio modem station, or as a station on a point-to-point link.

For information about See page

an overview of the tasks required to configure a MicroLogix 1100/1200/1500 controller

installing the controller 3-2 using modems that support DF1 communication protocol 3-6 modem control line operation 3-8 configuring DF1 half-duplex channel 0 parameters 3-11 configuring the controller as a DF1 half-duplex master station using

standard communication configuring the controller as a DF1 half-duplex master station using

message-based communication configuring the controller as a DF1 half-duplex slave station 3-22 configuring channel 0 poll timeout 3-25 configuring the controller as a DF1 radio modem station 3-27 configuring the controller for DF1 point-to-point communication 3-33

3-2

3-12

3-19

the types of DF1 messages you can send from a MicroLogix 1100/1200/1500 controller to another processor; how to configure the MSG instruction and some configuration characteristics

example MSG control blocks 3-42 configuring the controller a a Modbus RTU master station 3-46 configuring the controller as a Modbus RTU slave station 3-47 data logging 3-58 conditions that will erase the data retrieval file 3-69

1 Publication AG-UM008C-EN-P - February 2005

3-36

3-2 Configuring MicroLogix 1100/1200/1500 Controllers

Overview

RSLogix 500 Programming Software

To configure a MicroLogix 1100/1200/1500 controller:

1. Install the controller; connect the serial cable to one of the

communication channels.

2. Define the processor’s communication characteristics using

RSLogix

™ 500 programming software.

3. Install and configure the modem for communication with the

controller; connect the modem to one of the controller’s serial channels.

Figure 3.1 Configuring a MicroLogix 1100/1200/1500 Controller

Modem

MicroLogix 1500

Installing the Controller

Modem

For details about installing the controller, see the MicroLogix 1100 Installation Instructions, publication 1763-IN001, MicroLogix 1200 Installation Instructions, publication 1762-IN006 or the MicroLogix 1500 Installation Instructions, publication 1764-IN001. Cable pinouts are shown in each example configuration as well as in Appendix

IMPORTANT

The MicroLogix 1200/1500 channel 0 port is not

optically isolated. For all modem applications, an external optical isolator is recommended. You may either supply your own or use a 1761-NET-AIC. The MicroLogix 1500 Channel 1 port and MicroLogix Channel 0 port are optically isolated.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-3

MicroLogix 1200/1500 Channel 0 Cable Pinouts - User Supplied Optical Isolator

Standard Allen-Bradley cables include:

• 1761-CBL-PM02 Series B or higher (6.5 ft, 1.98 m)

• 1761-CBL-AP00 (17.7 in., 449.58 mm)

MicroLogix Optical Isolator Modem

8-pin

MiniDIN

(1)

DCD RXD 4 RXD 2 2 2 3 TXD 7 TXD 3 3 3 2 GND 2 GND 5 5 5 7

RTS 3 RTS 7 7 7 4 CTS 6 CTS 8 8 8 5

1761-CBL-PM02

1761-CBL-AP00

9-pin

9-pin male 9-pin 25-pin

female

DCD 1 1 1 8

DTR 4 4 4 20 DSR 6 6 6 6

(1) This pin is not active.

Figure 3.2 8-pin MiniDIN to 9-pin Cable Pinouts - User Supplied Optical Isolator

8 7 6

5 4 3

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3-4 Configuring MicroLogix 1100/1200/1500 Controllers

MicroLogix 1200/1500 Channel 0 Cable Pinouts - Allen-Bradley Supplied Optical Isolator

Standard Allen-Bradley cables include:

MicroLogix 1761-NET-AIC Modem

8-pin

MiniDIN

DCD RXD 4 RXD 4 RXD.IN 2 2 3 TXD 7 TXD 7 TXD.OUT 3 3 2 GND 2 GND 2 DTR.OUT 4 4 20 RTS 3 RTS 3 SIG.GND 5 5 7 CTS 6 CTS 6 DSR.IN 6 6 6

1761-CBL-HM02 1761-CBL-AM00

(1)

8-pin

MiniDIN

DCD 5 DCD.IN 1 1 8

• 1761-CBL-HM02 Series B or higher (6.5 ft, 1.98 m)

• 1761-CBL-AM00 (17.7 in., 449.58 mm)

9-pin female 9-pin 25-pin

RTS.OUT 7 7 4 CTS.IN 8 8 5

(1) This pin is not active.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-5

MicroLogix 1500 LRP Channel 1 Cable Pinouts

MicroLogix Modem

9-pin female 25-pin 9-pin

DCD.IN 1 8 1 RXD.IN 2 3 2 TXD.OUT 3 2 3

DTR.OUT

(1)

SIG.GND 5 7 5

(1)

DSR.IN

6 RTS.OUT 7 4 7 CTS.IN 8 5 8

(1) These pins are not active.

Figure 3.3 MicroLogix 1500 LRP Channel 1 Cable Pinouts

20 4

6 6

To modem

9-pin female cable connector

MicroLogix 1100 Channel 0 Cable Pinouts

MicroLogix Modem

8-pin

MiniDIN

DCD RXD 4 RXD 2 2 3 TXD 7 TXD 3 3 2 GND 2 GND 5 5 7

RTS 3 RTS 7 7 4 CTS 6 CTS 8 8 5

(1)

1761-CBL-PM02

1761-CBL-AP00

9-pin

9-pin 25-pin

female

DCD 1 1 8

DTR 4 4 20 DSR 6 6 6

(1) This pin is not active.

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3-6 Configuring MicroLogix 1100/1200/1500 Controllers

Using Modems that Support DF1 Communication Protocols

The types of modems that you can use with MicroLogix 1100/1200/1500 controllers include dial-up phone modems, leased-line modems, radio modems and line drivers. For point-to-point full-duplex modem connections, use DF1 full-duplex protocol. For general point-to-multipoint modem connections, use DF1 half-duplex master and slave protocols. In this case, one (and only one) of the other devices must be configured for DF1 half-duplex master protocol. For most radio modem connections, use DF1 radio modem protocol.

IMPORTANT

Do not attempt to use DH-485 protocol through modems under any circumstance.

Dial-up Phone Modems

Dial-up phone line modems support point-to-point full-duplex communications. Normally, a MicroLogix 1100/1200/1500 controller on the initiating or receiving end of the dial-up connection, will be configured for DF1 full-duplex protocol with the control line parameter set for no handshaking.

When a MicroLogix 1100/1200/1500 controller is the initiator of the dial-up connection, use one of the ASCII write instructions to send out the AT dial-up string (for example ATDT 555-1212). For the MicroLogix 1500 LRP channel 1 only, bit (CS1:9/3) provides the feedback that the connection has been successfully made. To hang up the connection, return the modem to Command Mode and use an ASCII Write instruction to send out the ATH hang-up string.

See Chapter 11 for further details on using MicroLogix 1100/1200/1500 controllers in dial-up modem applications.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-7

Leased-Line Modems

Leased-line modems are used with dedicated phone lines that are typically leased from the local phone company. The dedicated lines may be point-to-point topology supporting full-duplex communications between two modems or in a point-to-multipoint topology supporting half-duplex communications between three or more modems. In the point-to-point topology, configure the MicroLogix 1100/1200/1500 controllers for DF1 full-duplex protocol with the control line parameter set to Full-Duplex Modem. In the point-to-multipoint topology, configure the MicroLogix 1100/1200/1500 controllers for DF1 half-duplex master or slave protocol with the control parameter set to Half-Duplex Modem (RTS/CTS Handshaking).

Radio Modems

Radio modems may be implemented in a point-to-point topology supporting either half-duplex or full-duplex communications, or in a point-to-multipoint topology supporting half-duplex communications between three or more modems. In the point-to-point topology using full-duplex radio modems, configure the MicroLogix 1100/1200/1500 for DF1 radio modem protocol. In the point-to-multipoint topology using half-duplex radio modems, configure the MicroLogix 1100/1200/1500 for DF1 radio modem protocol. If these radio modems require RTS/CTS handshaking, configure the control line parameter to Half-Duplex Modem (RTS/CTS Handshaking).

Line Drivers

Line drivers, also called short-haul modems, do not actually modulate the serial data, but rather condition the electrical signals to operate reliably over long transmission distances (up to several miles). Allen-Bradley’s AIC+ Advanced Interface Converter is a line driver that converts an RS-232 electrical signal into an RS-485 electrical signal, increasing the signal transmission distance from 50 to 4000 feet. In a point-to-point line driver topology, configure the MicroLogix 1100/1200/1500 controllers for DF1 radio modem protocol. In a point-to-multipoint line driver topology, configure the MicroLogix 1100/1200/1500 for DF1 half-duplex master or slave protocol. If these line drivers require RTS/CTS handshaking, configure the control line parameter to Half-Duplex Modem (RTS/CTS Handshaking).

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3-8 Configuring MicroLogix 1100/1200/1500 Controllers

Modem Control Line Operation

The following explains the operation of the MicroLogix 1100/1200/1500 controllers when you configure the RS-232 channel for the following applications.

DF1 Full-Duplex

When configured for DF1 full-duplex, the following control line operation takes effect:

No Handshaking Selected

RTS is always inactive (low). Receptions and transmissions take place regardless of the state of CTS input. Only make this selection when the MicroLogix 1100/1200/1500 controllers are directly connected to another device that does not require handshaking signals.

Full-Duplex Modem (RTS On) Selected

RTS is always active (high).

Transmissions require CTS to be active.

DF1 Half-Duplex Slave

When configured for DF1 half-duplex slave, the following control line operation takes effect:

No Handshaking Selected

RTS is always inactive. Receptions and transmissions take place regardless of the state of CTS input. Only make this selection when the controller is directly connected to another device that does not require handshaking signals.

Half-Duplex Modem (RTS/CTS Handshaking) Selected

RTS is only activated during transmissions (and any programmed delays before or after transmissions). Transmissions require CTS to be active.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-9

DF1 Half Duplex Master

When configuring for DF1 half-duplex master, the following control line operation takes effect:

No Handshaking Selected

Full-Duplex Modem (RTS On) Selected

RTS is always active (high).

Transmissions require CTS to be active.

Half-Duplex Modem (RTS/CTS Handshaking) Selected

RTS is only active during transmissions (and any programmed delays before and after transmissions).

Transmissions require CTS to be active

DF1 Radio Modem

When you configure the MicroLogix 1100/1200/1500 controllers for DF1 Radio Modem, the following control line operation takes effect:

No Handshaking Selected

RTS is always inactive. Receptions and transmissions take place regardless of the state of CTS input. This selection should only be made when the processor is directly connected to another device that does not require handshaking signals.

Half-Duplex Modem (RTS/CTS Handshaking) Selected

RTS is activated during transmission and during any programmed delays before or after transmissions. Programmed delays include RTS Send Delay and RTS Off Delay.

Transmissions require CTS to be active. If CTS is inactive at the onset of transmission, one second will be provided to wait for CTS to become active before the message packet is discarded.

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3-10 Configuring MicroLogix 1100/1200/1500 Controllers

Half-Duplex Modem with DCD Handshaking (MicroLogix 1500 LRP Channel 1 Only) Selected

RTS is activated during transmissions and during any programmed delays before and after transmissions. Programmed delays include RTS Send Delay and RTS Off Delay. The DCD input signal is monitored to determine if transmissions are acceptable. If DCD is active, receptions are possible.

Transmissions require CTS to be active and DCD to be inactive. If DCD is active at the onset of transmission, a configured delay (DCD Wait Delay) will wait for DCD to become inactive before discarding the packet. If CTS is inactive at the onset of transmission, one second will be provided to wait for CTS to become active before the message packet is discarded.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-11

Configuring DF1 Half-Duplex Channel 0 Parameters

RTS Send Delay and RTS Off Delay

Through your programming software, the parameters RTS Send Delay and RTS Off Delay let you set how long RTS is on prior to transmission, as well as how long to keep it on after transmission is complete. These parameters only apply when you select half-duplex modem. For maximum communication throughput, leave these parameters at zero.

For use with half-duplex modems that require extra time to turnaround or key-up their transmitter even after they have activated CTS, the RTS Send Delay specifies (in 20 millisecond increments) the amount of delay time after activating RTS to wait before checking to see if CTS has been activated by the modem. If CTS is not yet active, RTS remains active, and as long as CTS is activated within one second, the transmission occurs. After one second, if CTS is still not activated, then RTS is set inactive and the transmission is aborted.

For modems that do not supply a CTS signal but still require RTS to be raised prior to transmission, jumper RTS to CTS and use the shortest delay possible without losing reliable operation.

IMPORTANT

Certain modems will drop their carrier link when RTS is set inactive even though the transmission has not quite been finished. The RTS Off Delay parameter specifies in 20 millisecond increments the delay between when the last serial character is sent to the modem and when RTS is deactivated. This gives the modem extra time to transmit the last character of a packet.

ATTENTION

If an RTS Send Delay of 0 is selected, then transmission starts as soon as CTS is activated. If CTS does not go active within one second after RTS is raised, RTS is set inactive and the transmission is aborted.

For almost all modem applications, the RTS Off Delay should be left at 0. Never select an RTS Off Delay that is greater than the RTS Send Delay in the other devices on the network, or you may incur two devices trying to transmit simultaneously.

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3-12 Configuring MicroLogix 1100/1200/1500 Controllers

Configuring a Standard-Mode DF1 Half-Duplex Master Station

1. To bring up the Channel

Configuration interface, double-click on the Channel Configuration icon.

Choose standard mode if you want to query slave stations for information based upon user-configured polling ranges. This mode is used most often in general point-to-multipoint configurations.

To configure the processor for a master station using standard communication, place the processor into program mode and follow the steps below using your programming software:

2. On the Channel tab, choose

DF1 Half-Duplex Master for your Driver.

3. Choose a Standard Polling

Mode.

4. Configure the rest of the

communication driver characteristics according to the table starting on page 3-13.

Use Worksheet 3.1 MicroLogix 1100/1200/1500 DF1 Half-Duplex Master Station Configuration Using Standard Communication (page D-9) for an example configuration and to record your station’s configuration.

The table starting on page 3-13 shows the parameters for configuring a MicroLogix 1100/1200/1500 controller as a master station using standard-communication mode to talk to slave stations.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-13

Table 3.1 MicroLogix 1100/1200/1500 Master Using Standard-Communication Mode

Parameter Selections

Baud Rate Select a communication rate that all devices in your system support. Configure all

devices in the system for the same communication rate.

Parity Parity provides additional message packet error detection. To implement even

parity checking, choose Even. To implement no parity checking, choose None.

Node Address A node address identifies the controller on the DF1 half-duplex link. Each station

on a link must have a unique address. Choose an address between 0 Node address 255

is the broadcast address, and cannot be selected as a

station’s individual address.

Control Line This parameter defines the mode in which the driver operates. Choose a method

appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If the master modem is full duplex, choose FULL-DUPLEX MODEM (RTS

ON).

• If all the modems in the system are half-duplex, choose HALF-DUPLEX

MODEM (RTS/CTS Handshaking).

See page 3-8 for a description of the control line operation settings.

and 254

10.

Error Detection With this selection, you choose how the controller checks the accuracy of each

DF1 packet transmission. BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security. Select an error detection method that all devices in your configuration can use. When possible, choose CRC.

Polling Mode If you want to receive:

• only one message from a slave station per its turn, choose STANDARD

(SINGLE MESSAGE TRANSFER PER NODE SCAN). Choose this method only if it is critical to keep the poll list scan time to a minimum.

• as many messages from a slave station as it has, choose STANDARD

(MULTIPLE MESSAGE TRANSFER PER NODE SCAN).

Duplicate Packet Detect Duplicate Detect lets the controller detect if it has received a message that is a

duplicate of its most recent message from another station. If you choose duplicate detect, the processor will acknowledge (ACK) the message but will not act on it since it has already performed the message’s task when it received the command from the first message. If you want to detect duplicate packets and discard them, check this parameter. If you want to accept duplicate packets and execute them, leave this parameter unchecked.

ACK Timeout The amount of time, in 20 millisecond increments, that you want the controller to

wait for an acknowledgment to the message it has sent before the processor retries the message or the message errors out. This timeout value is also used for the poll response timeout. See page

3-14 for recommendations to minimize this

value.

RTS Off Delay Defines the amount of time, in 20 millisecond increments, that elapses between

the end of the message transmission and the de-assertion of the RTS signal. This time delay is a buffer to make sure that the modem has transmitted the message but should normally be left at zero. See page

3-11 for further guidelines for setting

this parameter.

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3-14 Configuring MicroLogix 1100/1200/1500 Controllers

Table 3.1 MicroLogix 1100/1200/1500 Master Using Standard-Communication Mode

Parameter Selections

RTS Send Delay Defines the amount of time, in 20 millisecond increments, that elapses between

Pre-Transmit Delay Defines the amount of time in 1 millisecond increments that elapses between

Message Retries Defines the number of times a master station retries either:

Priority Polling Range – High Select the last slave station address to priority poll. Priority Polling Range – Low Select the first slave station address to priority poll. Entering 255 disables priority

Normal Polling Range – High Select the last slave station address to normal poll. Normal Polling Range – Low Select the first slave station address to normal poll. Entering 255 disables normal

the assertion of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The Clear-to-Send (CTS) signal must be high for transmission to occur. See page for further guidelines for setting this parameter.

when the processor has a message to send and when it asserts the RTS signal.

• a message before it declares the message undeliverable

• or a poll packet to an active station before the master station declares that

station to be inactive.

polling.

3-11

Normal Poll Group Size Enter the quantity of active stations located in the normal poll range that you want

polled during a scan through the normal poll range before returning to the priority poll range. If no stations are configured in the Priority Polling Range, leave this parameter at 0.

Minimum DF1 Half-Duplex Master Channel 0 ACK Timeout

The governing timeout parameter to configure for a DF1 Half-Duplex Master is the channel 0 ACK Timeout. The ACK Timeout is the amount of time you want the processor to wait for an acknowledgment of its message transmissions. Set in 20 millisecond intervals, the value is the amount of time the master will wait for:

• an ACK to be returned by a slave when the master has just sent

it a message, or

• a poll response or message to be returned by a slave when the

master has just sent it a poll packet.

The timeout must be long enough that after the master has transmitted the last character of the poll packet, there is enough time for a slave to transmit (and the master receive) a maximum-sized packet before the time expires.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-15

To calculate the minimum ACK timeout, you must know:

• the modem baud rate

• maximum-sized data packet (the maximum number of data

words that a slave write command or read reply packet might contain)

• the RTS/CTS or turnaround delay of the slave modem

• the configured RTS Send Delay in the slave

• the program scan time of the slave

Determining Minimum Master ACK Timeout

To determine the minimum ACK Timeout, you must first calculate the transmission time by multiplying the maximum-sized data packet for your processor by the modem rate in ms/byte. For an example we will assume a MicroLogix controller (103 data words or 224 bytes total packet size including overhead) and a 9600 bps modem, which transmits at approximately 1 ms/byte. Therefore, the message transmission time is 224 ms. For approximate modem transmission rates, see the following table.

Table 3.2 Approximate Modern Transmission Rates

modem bps approx. ms/byte

4800 2 ms/byte 9600 1 ms/byte 19200 0.5 ms/byte

Next, you need to determine the average slave program scan time. In RSLogix 500, double click on the Processor Status icon and then locate Average on the Scan Times tab. For this example, assume an average slave program scan time of 20 ms. The program scan time will vary by application.

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3-16 Configuring MicroLogix 1100/1200/1500 Controllers

Finally, you must determine the larger of two values, either the configured slave RTS Send Delay or the turnaround time of the slave modem. The RTS Send Delay time can be found by double-clicking on the slave’s Channel Configuration icon and looking at the particular channel tab of the Channel Configuration screen. Note that the RTS Send Delay time is in intervals of 20 ms, so with a value of 3 in the box, the RTS Send Delay time would be 20 ms multiplied by 3. Using this value (60 ms) for our example, and assuming that the turnaround time of the modem is 50 ms (which will vary by modem), you would choose to use the RTS Send Delay time of 60 ms for your calculation.

Having determined the maximum message transmission time (224 ms), the average slave program scan time (20 ms) and the largest of either RTS Send Delay (60 ms) or the modem turnaround time, the minimum ACK timeout is simply the sum of these values.

Parameter Example Values (in ms)

Use only the largest of these two values.

Max message transmission time

Average program scan time 20 RTS Send Delay 60 modem turnaround time 50 calculated ACK Timeout 304 round up to nearest 20 ms 320

224

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1. Double-click on the Channel

Status icon located beneath the Configuration icon to bring up the Channel Status interface.

Configuring MicroLogix 1100/1200/1500 Controllers 3-17

DF1 Half-Duplex Master Channel Status

Channel Status data is stored in the Communication Status Function File.

Table 3.3 explains information regarding the diagnostic counter

data displayed.

2. See Table 3.3 for details

concerning the DF1 Half-Duplex Master Channel Status interface.

Table 3.3 Understanding the DF1 Half-Duplex Master Status Screen Fields

Status Field Communication Status

Function File Location

Definition

(2)

Messages Sent CSx:10 The total number of DF1 messages sent by the processor (including message

retries) Messages Received CSx:11 The number of messages received with no errors Poll Sent CSx:15 The total number of poll packets sent by the controller Lack of Memory CSx:17 The number of packets dropped due to lack of memory Last Normal Poll List Scan CSx:19 Time in 100 ms increments of last scan through Normal Poll List Last Priority Poll List Scan CSx:21 Time in 100 ms increments of last scan through Priority Poll List Message Retried CSx:13 The number of message retries sent by the processor

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3-18 Configuring MicroLogix 1100/1200/1500 Controllers

Table 3.3 Understanding the DF1 Half-Duplex Master Status Screen Fields

Status Field Communication Status

Function File Location

Undelivered Messages CSx:12 The number of messages that were sent by the controller but not

Duplicate Messages Received

Bad Packet Received CSx:16 The number of incorrect data packets received by the controller for which no

Max Normal Poll List Scan CSx:20 Maximum time in 100 ms increments to scan the Normal Poll List Max Priority Poll List Scan CSx:22 Maximum time in 100 ms increments to scan the Priority Poll List RTS (Request to Send) CSx:9/1 The status of the RTS handshaking line (asserted by the processor) CTS (Clear to Send) CSx:9/0 The status of the CTS handshaking line (received by the processor)

DCD (Data Carrier Detect)

(1) Only present on the MicroLogix 1500 LRP channel 1.

(2) The channel number equals x.

CSx:18 The number of times the controller received a message packet identical to

CSx:9/3 The status of the DCD handshaking line (received by the processor)

(1)

Definition

(2)

acknowledged by the destination device

the previous message packet

ACK was returned

Monitor Active Stations

To see what slave stations are active when the channel is configured for Standard Polling Mode (either single or multiple message per scan), view the DF1 Half-Duplex Master Active Node Table. The table is stored in the Communications Status Function File, words CSx:27 to CSx:42, where x is the channel number (x=0 for MicroLogix 1100, 1200 and MicroLogix 1500 1764-LSP; x=1 for MicroLogix 1500 1764-LRP). Each bit in the table represents a station on the link, from 0 to 254, starting with CSx:27/0 for address 0 and CSx:42/14 for address

254. The bit for address 255 (CSx:42/15) is never set, since it is the broadcast address which never gets polled.

When valid Normal and/or Priority Poll Ranges are defined:

• if a slave responded the last time it was polled by the master, the

bit corresponding to its address is set (1=active).

• if a slave did not respond the last time it was polled by the

master, the bit corresponding to its address is cleared (0=inactive).

TIP

The bit corresponding to the address configured for the DF1 Master is always cleared because the master address never gets polled.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-19

If you are using RSLogix 500 version 6.10.10 or higher, you can view the active node table by clicking on Processor Status and then selecting the tab for the DF1 Master channel.

Figure 3.4 Example Active Node Table

Configuring a Message-based Mode DF1 Half-Duplex Master Station

At powerup or after reconfiguration, the master station assumes that all slave stations are inactive. A station is shown active only after it responds to a poll packet.

With message-based mode, you do not have an active node file that you can use to monitor station status. Also, you cannot implement slave station-to-slave station messaging or slave programming.

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3-20 Configuring MicroLogix 1100/1200/1500 Controllers

To configure the processor for a master station using message-based communication, place the processor in program mode and follow the steps below using your programming software:

1. To bring up the Channel

Configuration interface, double-click on the Channel Configuration icon.

2. On the Channel 1 tab, choose

DF1 Half-Duplex Master for your Driver.

3. Choose a Message-based

Polling Mode.

4. Configure the communication

driver characteristics according to Table 3.4.

Use Worksheet 3.2 MicroLogix 1100/1200/1500 DF1 Half-Duplex Master Station Configuration Using Message-based Communication (page D-10) for an example configuration and to record your station’s configuration.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-21

Define the parameters shown in Table 3.4 when configuring a MicroLogix 1100/1200/1500 controller as a master station using message-based communication mode to talk to slave stations.

Table 3.4 Configuring a MicroLogix 1100/1200/1500 as a Master Using Message-based Communication Mode

Parameter Selections

Baud Rate Select a communication rate that all devices in your system support. Configure all devices in the

system for the same communication rate.

Parity Parity provides additional message packet error detection. To implement even parity checking,

choose Even. To implement no parity checking, choose None.

Node Address A node address identifies the controller on the DF1 half-duplex link. Each station on a link must

have a unique address. Choose an address between 0 broadcast address, and cannot be selected as a station’s individual address.

Control Line This parameter defines the mode in which the driver operates. Choose a method appropriate for

your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If the master modem is full duplex, choose FULL-DUPLEX MODEM (RTS On).

• If all the modems in the system are half-duplex, choose HALF-DUPLEX MODEM

(RTS/CTS Handshaking).

See page 3-8 for descriptions of control line operation settings.

and 254

Node address 25510 is the

10.

Error Detection With this selection, you choose the how the processor checks the accuracy of each DF1 packet

transmission. BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security. Select an error detection method that all devices in your configuration can use. When possible, choose CRC.

Polling Mode If you want to:

• accept unsolicited messages from slave stations, choose MESSAGE BASED (ALLOW

SLAVES TO INITIATE MESSAGES) Slave station-initiated messages are acknowledged and processed after all master station-initiated (solicited) messages. Note: Slave stations can only send messages when they are polled. If the message-based master station never sends a slave station a message, the master station will never send the slave station a poll. Therefore, to regularly obtain a slave station-initiated message from a slave station, you should choose to use standard communication mode instead.

• ignore unsolicited messages from slave stations, choose MESSAGE BASED (DO NOT

ALLOW SLAVES TO INITIATE MESSAGES) Slave station-initiated messages are acknowledged and discarded. The master station acknowledges the slave station-initiated message so that the slave station removes the message from its transmit queue, which allows the next packet slated for transmission into the transmit queue.

Duplicate Packet Detect

Duplicate Detect lets the controller detect if it has received a message that is a duplicate of its most recent message from another station. If you choose duplicate detect, the processor will acknowledge (ACK) the message but will not act on it since it has already performed the message’s task when it received the command from the first message. If you want to detect duplicate packets and discard them, check this parameter. If you want to accept duplicate packets and execute them, leave this parameter unchecked.

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3-22 Configuring MicroLogix 1100/1200/1500 Controllers

Table 3.4 Configuring a MicroLogix 1100/1200/1500 as a Master Using Message-based Communication Mode

Parameter Selections

Reply Message Wait Timeout

ACK Timeout The amount of time, in 20 millisecond increments, that you want the controller to wait for an

RTS Off Delay Defines the amount of time, in 20 millisecond increments, that elapses between the end of the

RTS Send Delay Defines the amount of time, in 20 millisecond increments, that elapses between the assertion

Pre-Transmit Delay Defines the amount of time, in 1 millisecond increments, that elapses between when the

Message Retries Defines the number of times a master station retries a message before it declares the message

Defines the amount of time, in 20 millisecond increments, that the master station will wait after receiving an ACK (to a master-initiated message) before polling the slave station for a reply. Choose a time that is, at minimum, equal to the longest time that a slave station needs to format a reply packet. This would typically be the maximum scan time of the slave station.

acknowledgment to the message it has sent before the processor retries the message or the message errors out. This timeout value is also used for the poll response timeout. See page 3-14 for recommendations to minimize this value.

message transmission and the de-assertion of the RTS signal. This time delay is a buffer to make sure that the modem has transmitted the message but should normally be left at zero. See page

3-11 for further guidelines for setting this parameter.

of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The Clear-to-Send (CTS) signal must be high for transmission to occur. See

processor has a message to send and when it asserts the RTS signal.

undeliverable.

page 3-11 for further guidelines for setting this parameter.

Configuring a Slave Station

1. To bring up the Channel

Configuration interface, double-click on the Channel Configuration icon.

To choose the processor as a slave station, follow the steps below using your programming software:

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2. On the Channel tab, choose

DF1 Half-Duplex Slave for your Driver.

3. Configure the communication

driver characteristics according to Table 3.5.

Configuring MicroLogix 1100/1200/1500 Controllers 3-23

Use Worksheet 3.3 MicroLogix 1100/1200/1500 DF1 Half-Duplex Slave Station Configuration (pageD-11) for an example configuration and to record your station’s configuration.

Define these parameters when configuring a MicroLogix 1100/1200/1500 controller as a slave station.

Table 3.5 Configuring a MicroLogix 1100/1200/1500 controller as a Slave Station

Parameter Selections

Baud Rate Select a communication rate that all devices in your system support. Configure all

devices in the system for the same communication rate.

Parity Parity provides additional message packet error detection. To implement even parity

checking, choose Even. To implement no parity checking, choose None.

Node Address A node address identifies the controller on the DF1 half-duplex link. Each station on a

link must have a unique node address. Choose an address between 0 address 255 individual address.

Control Line This parameter defines the mode in which the driver operates. Choose a method

appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• If the master modem is full duplex and the slave modem is half-duplex, choose

See page 3-8 for descriptions of the control line operation settings.

is the broadcast address, which you cannot select as a station’s

HALF-DUPLEX MODEM (RTS/CTS Handshaking).

and 254

10.

Node

Error Detection With this selection, you choose how the controller checks the accuracy of each DF1

packet transmission. BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security. Select an error detection method that all devices in your configuration can use. When possible, choose CRC.

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3-24 Configuring MicroLogix 1100/1200/1500 Controllers

Table 3.5 Configuring a MicroLogix 1100/1200/1500 controller as a Slave Station

Parameter Selections

Duplicate Packet Detect Duplicate Detect lets the controller detect if it has received a message that is a

duplicate of its most recent message from the master station. If you choose duplicate detect, the processor will acknowledge (ACK) the message but will not act on it since it has already performed the message’s task when it received the command from the first message. If you want to detect duplicate packets and discard them, check this parameter. If you want to accept duplicate packets and execute them, leave this parameter unchecked.

Poll Timeout The timer keeps track of how often the station is polled. If the station has a message to

send, it starts a timer. If the poll timeout expires before the message timeout, which you specify in the MSG control block, the MSG error bit is set and the message is removed from the transmit queue. If the message timeout, which you specify in the MSG control block, expires before the poll timeout expires, the MSG error bit and MSG timeout bit are set. The poll timeout can be disabled by entering a zero. See page 3-25 for recommendations to minimize this value.

RTS Off Delay Defines the amount of time, in 20 millisecond increments, that elapses between the

end of the message transmission and the de-assertion of the RTS signal. This time delay is a buffer to make sure that the modem has transmitted the message, but should normally be left at zero. See page

3-11 for further guidelines for setting this parameter.

RTS Send Delay Defines the amount of time, in 20 millisecond increments, that elapses between the

assertion of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The Clear-to-Send (CTS) signal must be high for transmission to occur.See page

3-11 for further guidelines for setting

this parameter.

Message Retries Defines the number of times a slave station resends its message to the master station

before the slave station declares the message undeliverable.

Pre-Transmit Delay Defines the amount of time in 1 millisecond increments that elapses between when the

processor has a message to send and when it asserts the RTS signal.

EOT Suppression If you want to minimize traffic on the network, you can choose to have the slave station

not send EOT packets to the master station. When EOT packets are suppressed, the master station automatically assumes a slave station has no data to give if the slave station does not send a message packet as a response to a poll.

A disadvantage of suppressing EOTs is that the master station cannot distinguish between an active station that has no data to transmit and an inactive station.

A possible application for suppressing EOTs is the following: conserving power with a radio modem because the radio transmitter does not have to power-up to transmit a DLE EOT packet (”no data to give” packet).

To suppress EOTs, check this parameter. To have the processor send EOTs, leave this parameter unchecked.

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Configuring MicroLogix 1100/1200/1500 Controllers 3-25

Configuring Poll Timeout

The Poll Timeout is only used when the DF1 half-duplex slave is initiating MSG instructions in ladder logic. This implies that the Master is most likely configured for Standard Polling Mode. The minimum Poll Timeout value is dependent on the maximum Master poll scan rate. Since the Master’s polling and the Slave’s triggering of a MSG instruction are asynchronous events, it is possible that in the instant just after the slave was polled, the MSG instruction gets triggered. This means the MSG instruction will remain queued-up for transmission until the Master has polled every other slave first. Therefore, the minimum Slave channel 0 Poll Timeout value is equal to the maximum Master poll scan rate rounded up to the next 20 ms increment.

Minimum Channel 0 Poll Timeout = Maximum Master Scann Poll Rate

DF1 Half-Duplex Slave Channel Status

Channel Status data is stored in the Communication Status Function file. Table diagnostic counter data displayed.

3.6 on page 3-25 explains information regarding the

1. Double-click on the Channel

Status Icon Located beneath the Configuration icon to bring up the Channel Status screen.

Table 3.6 Understanding the DF1 Half-Duplex Slave Status Screen Fields

Status Field Communication Status

Function File Location

Messages Sent CSx:10 The total number of DF1 messages sent by the processor (including

Messages Received CSx:11 The number of messages received with no errors Polls Received CSx:15 The number of master poll packets received by the processor Received NAK CSx:14 The number of NAKs received by the processor Lack of Memory CSx:17 The number of times the processor could not receive a message because

(2)

Definition

message retries)

it did not have available memory

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3-26 Configuring MicroLogix 1100/1200/1500 Controllers

Table 3.6 Understanding the DF1 Half-Duplex Slave Status Screen Fields

Status Field Communication Status

Function File Location

(2)

Definition

Messages Retried CSx:13 The number of message retries sent by the processor Undelivered Messages CSx:12 The number of messages that were sent by the processor but not

acknowledged by the destination device

Duplicate Messages Received

CSx:18 The number of times the processor received a message packet identical

to the previous message packet

Bad Packet Received CSx:16 The number of incorrect data packets received by the processor for which

no ACK was returned RTS (Request to Send) CSx:9/1 The status of the RTS handshaking line (asserted by the processor) CTS (Clear to Send) CSx:9/0 The status of the CTS handshaking line (received by the processor)

DCD (Carrier Detect)

(1) Only present on the MicroLogix 1500 LRP channel 1.

(2) The channel number equals x.

(1)

CSx:9/3 The status of the DCD handshaking line (received by the processor)

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Configuring MicroLogix 1100/1200/1500 Controllers 3-27

Configuring a Radio Modem Station

1. To bring up the Channel

Configuration interface, double-click on the Channel Configuration icon.

To configure a MicroLogix 1100/1200/1500 controller channel 1 for DF1 Radio Modem, do the following using your programming software:

2. On the Channel tab, choose

DF1 Radio Modem for your Driver.

3. Configure the communication

driver characteristics according to Table 3.7.

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3-28 Configuring MicroLogix 1100/1200/1500 Controllers

Table 3.7 Define these communication parameters when configuring a MicroLogix 1100/1200/1500

controller for DF1 Radio Modem communication.

Parameter Default Selections

Baud Rate 19,200 Select a communication rate that all devices in your system support.

Configure all devices in the system for the same communication rate.

Parity None Parity provides additional message packet error detection. To

implement even parity checking, choose Even. To implement no parity checking, choose None.

Node Address 1 A node address identifies the processor on the DF1 half-duplex link.

Each station on a link must have a unique node address. Choose an address between 0

address, which you cannot select as a station’s individual address.

and 254

Node address 25510 is the broadcast

10.

Store and Forward File Number

0 Select an unused file (9 to 255) to be the 256-bit Store and Forward

table. Zero disables Store and Forward. Refer to Configuring the Store and Forward table for more information.

Control Line No Handshaking This parameter defines the mode in which the driver operates.

Choose a method appropriate for your system’s configuration:

• If you are not using a modem, choose NO HANDSHAKING.

• Half-Duplex Modem (RTS/CTS Handshaking)

(1)

• Half-Duplex Modem with DCD Handshaking

See page 3-8 for descriptions of the control line operation settings

Error Detection CRC With this selection, you choose the how the processor checks the

accuracy of each DF1 packet transmission.

BCC: This algorithm provides a medium level of data security. It cannot detect:

• transposition of bytes during transmission of a packet

• the insertion or deletion of data values of zero within a packet

CRC: This algorithm provides a higher level of data security.

Select an error detection method that all devices in your configuration can use.

RTS Off Delay 0 Defines the amount of time, in 20 millisecond increments, that

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When possible, choose CRC.

elapses between the end of the message transmission and the de-assertion of the RTS signal. This time delay is a buffer to make sure that the modem has transmitted the message, but should normally be left at zero. See page

3-11 for further guidelines for

setting this parameter.

Table 3.7 Define these communication parameters when configuring a MicroLogix 1100/1200/1500

controller for DF1 Radio Modem communication.

Parameter Default Selections

RTS On Delay

0 Defines the amount of time, in 20 millisecond increments, that

elapses between the assertion of the RTS signal and the beginning of the message transmission. This time allows the modem to prepare to transmit the message. The Clear-to-Send (CTS) signal must be high for transmission to occur. See page setting this parameter.

(1)

DCD Wait Delay

1 Only used with Half-Duplex Modem with DCD Handshaking Control

Line setting. Defines how long, in seconds, the processor will wait for DCD to go low so that it can transmit, before giving up and erroring out MSG.

Pre-Transmit Delay 0 Defines the amount of time, in 1 millisecond increments, that elapses

between when the processor has a message to send and when it asserts the RTS signal (if handshaking is selected) or begins transmitting (if no handshaking is selected).

(1) MicroLogix 1500 LRP Channel 1 only.

Configuring MicroLogix 1100/1200/1500 Controllers 3-29

3-11 for further guidelines for

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3-30 Configuring MicroLogix 1100/1200/1500 Controllers

DF1 Radio Modem Channel Status

Channel status data is stored in the Communication Status Function file. data displayed.

1. Double-click on the Channel

Status Icon Located beneath the Configuration icon to bring up the Channel Status screen.

See Table 3.8 for information regarding the diagnostic counter

2. See Table 3.8 for details

concerning the DF1 Radio Modem Channel Status Screen.

Table 3.8 Understanding the DF1 Radio Modem Channel Status

Status Field Communication Status

Function File Location

(2)

Definition

Messages Sent CSx:10 The total number of DF1 messages sent by the controller Messages Received CSx:11 The number of messages received with no errors Lack of Memory/Packet

Dropped

CSx:17 The number of times the controller could not receive a message because

it did not have available memory Undelivered Messages CSx:12 The number of messages that could not be sent by the controller because

of incorrect modem handshaking conditions.

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Table 3.8 Understanding the DF1 Radio Modem Channel Status

Configuring MicroLogix 1100/1200/1500 Controllers 3-31

Status Field Communication Status

Function File Location

Duplicate Messages Received

Bad Packets Received CSx:16 The number of data packets received with transmission errors by the

RTS (Request to Send) CSx:9/1 The status of the RTS handshaking line (asserted by the processor) CTS (Clear to Send) CSx:9/0 The status of the CTS handshaking line (received by the processor)

DCD (Data Carrier Detect)

(1) Only present on the MicroLogix 1500 LRP channel 1.

(2) The channel number equals x.

CSx:18 The number of times the processor received a message packet identical

CSx:9/3 The status of the DCD handshaking line (received by the processor)

(1)

(2)

Definition

to the previous message packet

processor

For the MicroLogix 1500 LRP, clicking the Clear button while monitoring Channel Status of either channel 1 or channel 0 online, will reset all of the channel status diagnostic counters for both channels to zero.

Configuring the Store & Forward Table

The Store & Forward Table occupies a 16-word binary data table file. Each bit in this file corresponds to a DF1 Radio Modem node address. In order to configure a MicroLogix to Store & Forward message packets between two other nodes, the bits corresponding to the addresses of those two other nodes must be set. For instance, if node 2 is used to Store & Forward message packets between nodes 1 and 3, then both bits Bx/1 and Bx/3 would have to be set in the Store & Forward Table (see

Figure 3.6). You can set bit 255 to enable Store &

Forward of broadcast packets, as well.

IMPORTANT

Once Store & Forward is enabled, duplicate packet detection is also automatically enabled. Whenever Store & Forward is used within a radio modem network, every node should have Store & Forward enabled, even if all of the bits in the file are cleared, so that duplicate packets will be ignored.

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3-32 Configuring MicroLogix 1100/1200/1500 Controllers

Figure 3.5 Applying Store and Forward with DF1 Radio Modem Protocol

(2nd Rebroadcast)

REPLY 1

Node 1

CMD 1

No Bits

Note 1

Note 1 – The link layer of Node 1 blocks the re-transmission of a packet that is received with the SRC byte equal to the

receiving node’s station address. Packets received that originate from the receiving node should never be re-transmitted.

Note 2 – To prevent Node 2 from re-transmitting a duplicate packet, the link layer of Node 2 updates the duplicate packet table with the last 20 packets received.

Note 3 – The link layer of Node 4 blocks the re-transmission of a packet that is received with the SRC byte equal to the receiving node’s station address. Packets received that originate from the receiving node should never be re-transmitted.

Note 4 – To prevent Node 3 from re-transmitting a duplicate packet, the link layer of Node 3 updates the duplicate packet table with the last 20 packets received.

(DST = 4, SRC = 1)

Node 2

1, 3, 4

CMD1

(1st Rebroadcast)

Note 2

Note 4

(1st Rebroadcast)

REPLY 1

Node 3

1, 2, 4

CMD 1

(2nd Rebroadcast)

Note 3

REPLY 1

(DST = 1, SRC = 4)

Node 4

No Bits

Figure 3.6 Store & Forward Table for Node 2

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Rockwell Automation DAG6.5.8 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Important User Information

Summary of Changes

Table of Contents

Preface

What SCADA Information Is Available?

Audience

Contents of this Manual

Terms

Address Conventions

Related Publications

Designing Communication

Chapter Objectives

Choosing a Polling Mode for DF1 Half-Duplex Master

Communication Scheme Design Using Standard-Mode

Communication Scheme Design Using Message-Based Mode

Designing Communication for DF1 Full-Duplex Protocol

Designing Communication for DF1 Radio Modem Protocol

What to Do Next?

Configuring Enhanced PLC-5 Processors

Chapter Objectives

Overview

Installing the Processor

Configuring a DF1 Half-Duplex Standard Mode Master Station

Configuring a DF1 Half-Duplex Message-based Mode Master Station

Configuring the Processor as a Slave Station

Configuring the Processor as a Station on a Point-to-Point Link

Messaging

Configuring MicroLogix 1100/1200/1500 Controllers

Chapter Objectives

Overview

Installing the Controller

Using Modems that Support DF1 Communication Protocols

Modem Control Line Operation

Configuring DF1 Half-Duplex Channel 0 Parameters

Configuring a Standard-Mode DF1 Half-Duplex Master Station

Configuring a Message-based Mode DF1 Half-Duplex Master Station

Configuring a Slave Station

Configuring Poll Timeout

Configuring a Radio Modem Station