Communicate over Networks. Allen-Bradley 1769-L35CR CompactLogix 5335CR, 1769-L31 CompactLogix 5331, 1769-L32C CompactLogix 5332C, 1769 CompactLogix, 1769-L35E CompactLogix 5335E, 1769-L32E CompactLogix 5332E

Chapter

4

Communicate over Networks

This chapter explains how CompactLogix controllers support additional networks to enable various functions.

Table 4 - CompactLogix Controller Network Support

Example Function

Control distributed (remote) I/O.

• EtherNet/IP

• ControlNet

• DeviceNet

CompactLogix Controller

DeviceNet Network

Distributed (remote)

I/O Platform

Produce/consume (interlock) data between controllers.

• EtherNet/IP

• ControlNet


ControlNet Network

Other Logix5000

Controller

Send and receive messages to and from other devices.

This includes access to the controller via RSLogix 5000 programming software.

• EtherNet/IP

• ControlNet

• DeviceNet (to devices only)

• serial

• DH-485


EtherNet/IP Network

Other Remote Devices

Topic

EtherNet/IP Network Communication

ControlNet Network Communication

DeviceNet Communication

Serial Communication

DH-485 Network Communication

Rockwell Automation Publication 1769-UM011H-EN-P - April 2012

55

72

50

53

Page

48

47

Chapter 4

Communicate over Networks

EtherNet/IP Network

Communication

The EtherNet/IP network offers a full suite of control, configuration and data collection services by layering the Common Industrial Protocol (CIP) over the standard Internet protocols, such as TCP/IP and UDP. This combination of well-accepted standards provides the capability required to both support information data exchange and control applications.

The EtherNet/IP network also uses commercial, off-the-shelf Ethernet components and physical media, providing you with a cost-effective plant-floor solution.

For EtherNet/IP communication, you can use these CompactLogix controllers with a built-in EtherNet/IP communication port:

• 1769-L32E CompactLogix controller

• 1769-L35E CompactLogix controller

You can use several software products with a 1769 CompactLogix controller on an EtherNet/IP network.

Table 5 - EtherNet/IP Network Software Combinations

Software Functions

RSLogix 5000 programming software • Configure the CompactLogix project

• Define EtherNet/IP communication

BOOTP/DHCP utility with RSLogix

5000 programming software

RSNetWorx software for an

EtherNet/IP network

Assign IP addresses to devices on an

EtherNet/IP network

Configure EtherNet/IP devices by IP addresses and/or host names

Requirement

Yes

No

No

The EtherNet/IP communication modules:

• support messaging, produced/consumed tags, HMI, and distributed I/O.

• encapsulate messages within standard TCP/UDP/IP protocol.

• share a common application layer with ControlNet and DeviceNet.

• interface via RJ45, category 5, unshielded, twisted-pair cable.

• support half/full-duplex 10 Mbps or 100 Mbps operation.

• support standard switches.

• require no network scheduling.

• require no routing tables.

In this example:

• the controllers produce and consume tags amongst themselves.

• the controllers initiate MSG instructions that send and receive data or configure devices.

• the personal computer uploads or downloads projects to the controllers.

• the personal computer configures devices on an EtherNet/IP network.

48


CompactLogix Controller with

Integrated EtherNet/IP Port

PowerFlex 700S AC Drive with DriveLogix


Chapter 4

Figure 4 - CompactLogix EtherNet/IP Overview

FlexLogix Controller with

1788-ENBT Module

CompactLogix

Controller with

1756-ENBT Module

Distributed I/O

1756-ENBT Module

(as an adapter) with 1756 I/O

Modules

Switch

1794-AENT Adapter with 1794

I/O Modules

1734-AENT Adapter with 1734 I/O Modules

Workstation

Connections over an EtherNet/IP Network

You indirectly determine the number of connections the controller uses by configuring the controller to communicate with other devices in the system.

Connections are allocations of resources that provide more reliable communication between devices than unconnected messages.

All EtherNet/IP connections are unscheduled. An unscheduled connection is a message transfer between controllers that is triggered by the requested packet interval (RPI) or the program, such as a MSG instruction. Unscheduled messaging lets you send and receive data when needed.


49

Chapter 4


ControlNet Network

Communication

The 1769-L32E and 1769-L35E controllers support 100 connections. However, the built-in EtherNet/IP port supports only 32 CIP connections over an

EtherNet/IP network. With these controllers, the number of end-node connections they effectively support depends on a connection’s RPI.

Requested Packet Interval

2 ms

4 ms

8 ms

16 ms

32 ms+

5

10

Max EtherNet/IP Port Communication Connections

2

18

25+

You can use all 32 communication connections on the built-in EtherNet/IP port.

However, we recommend that you leave some connections available for tasks such as going online and non-I/O purposes.

ControlNet is a real-time control network that provides high-speed transport of both time-critical I/O and interlocking data and messaging data, including uploading and downloading of programming and configuration data on a single physical-media link. The ControlNet network’s highly-efficient data transfer capability significantly enhances I/O performance and peer-to-peer communication in any system or application.

The ControlNet network is highly deterministic and repeatable and remains unaffected as devices are connected or disconnected from the network. This robust quality results in dependable, synchronized, and coordinated real-time performance.

The ControlNet network often functions as:

• the default network for the CompactLogix platform.

• a substitute/replacement for the remote I/O (RIO) network because the

ControlNet network adeptly handles large numbers of I/O points.

• a backbone to multiple distributed DeviceNet networks.

• a peer interlocking network.

For ControlNet communication, you can use these CompactLogix controllers with a built-in ControlNet communication port:

• 1769-L32C CompactLogix controller

• 1769-L35CR CompactLogix controller

50



Chapter 4

You can use these software products with a 1769 CompactLogix controller on a

ControlNet network.

Table 6 - ControlNet Network Software Combinations

Software Functions



RSNetWorx for ControlNet software • Configure the ControlNet network

• Define the NUT (network update time)

• Schedule the ControlNet network

Requirement

Yes

The ControlNet communication modules:

• support messaging, produced/consumed tags and distributed I/O.

• share a common application layer with DeviceNet and EtherNet/IP networks.

• require no routing tables.

• support the use of coax and fiber repeaters for isolation and increased distance.

In this example:

• the controllers produce and consume tags amongst themselves.

• the controllers initiate MSG instructions that send and receive data or configure devices.

• the personal computer uploads or downloads projects to the controllers.

• the personal computer configures devices on ControlNet, and configures the network itself.


51

Chapter 4


Figure 5 - CompactLogix ControlNet Overview

Personal Computer/Workstation


PowerFlex 700S Drive

Distributed I/O

1756-CNB Module (as an adapter) with 1756 I/O

Modules

ControlNet Network

FlexLogix Controller with

1788-CNC Card

PLC-5/40C15 Controller

PanelView Terminal

1794-ACN15 Adapter with

1794 I/O Modules

1734-ACNR Adapter with

1734 I/O Modules

Connections over ControlNet

You indirectly determine the number of connections the controller uses by configuring the controller to communicate with other devices in the system.

Connections are allocations of resources that provide more reliable communication between devices compared to unconnected messages.

Table 7 - ControlNet Connection Methods

Connection Method

Scheduled

Unscheduled

Description

A scheduled connection is unique to ControlNet communication. A scheduled connection lets you send and receive data repeatedly at a set interval, which is the requested packet interval (RPI). For example, a connection to an I/O module is a scheduled connection because you repeatedly receive data from the module at a specified interval. Other scheduled connections include connections to:

•

communication devices.

•

produced/consumed tags.

On a ControlNet network, you must use RSNetWorx for ControlNet to enable all scheduled connections and establish a network update time (NUT).

Scheduling a connection reserves network bandwidth to specifically handle the connection.

An unscheduled connection is a message transfer between nodes that is triggered by ladder logic or the program (such as a MSG instruction).

Unscheduled messaging lets you send and receive data when needed. Unscheduled messages use the remainder of network bandwidth after scheduled connections are allocated.

52



Chapter 4

The 1769-L32C and 1769-L35CR controllers support 100 connections.

However, the built-in ControlNet port only supports 32 communication connections. With these controllers, the number of end-node connections they effectively support depends on the connection’s NUT and RPI.

10 ms

14 ms

5 ms

4 ms

NUT

2 ms

3 ms

5 ms

RPI

2 ms

3 ms

5 ms

10 ms

14 ms

20 ms

64 ms

Supported ControlNet Communication Connections

(1)

0...1

1...2

3...4

6...9

10...12

12...16

31

(1) For each NUT/RPI combination, the number of connections supported is listed in a range. The lower number is the number of connections we recommend you make to maintain reasonable ControlNet port CPU utilization rates. The higher number is the maximum number of connections possible for that NUT/RPI combination.

You can use all 32 communication connections on the built-in ControlNet port.

However, we recommend that you leave some connections available for tasks such as going online and unscheduled network traffic.

DeviceNet Communication

The DeviceNet network uses the Common Industrial Protocol (CIP) to provide the control, configuration, and data collection capabilities for industrial devices.

The DeviceNet network uses the proven Controller Area Network (CAN) technology, which lowers installation costs and decreases installation time and costly downtime.

A DeviceNet network provides access to the intelligence present in your devices by letting you connect devices directly to plant-floor controllers without having to hard wire each device into an I/O module.

Table 8 - CompactLogix DeviceNet Communication Interfaces

If your application

· Communicates with other DeviceNet devices

· Uses the controller as a master or slave on DeviceNet

· Uses a controller ControlNet, Ethernet or serial port for other communication

· Accesses remote Compact I/O over a DeviceNet network

· Sends remote I/O data for as many as 30 modules back to scanner or controller

Select

1769-SDN DeviceNet scanner module

1769-ADN DeviceNet adapter module

(1)

(1) This table specifically describes using the 1769-ADN module to access remote Compact I/O over DeviceNet. However, CompactLogix controllers can access other Allen-Bradley remote I/O over DeviceNet. In those cases, you must select the appropriate interface. For example, if accessing remote POINT I/O modules, you must select the 1734-ADN.


53

Chapter 4


CompactLogix

Controller with 1769-SDN

Figure 6 - CompactLogix DeviceNet Overview

PLC-5 Controller with 1771-SDN

Scanner Module

DeviceNet Network

ControlLogix Controller with

1756-DNB Module

CompactLogix System with

1769-ADN

PanelView

Terminal

Laptop

Motor

Starter

Ultra 5000

Servo Drive

Input/Output

Devices

PowerFlex AC

Drive

Sensor

Indicator

Lights

Pushbutton

Cluster

Bar Code

Scanner

You can use these software products with a 1769 CompactLogix controller on a

DeviceNet network.

Table 9 - CompactLogix DeviceNet Software Combinations

Software

RSNetWorx software for DeviceNet

Functions



• Configure DeviceNet devices

• Define the scan list for DeviceNet devices

Requirement

Yes

The DeviceNet communication module:

• supports messaging to devices, not controller to controller.

• shares a common application layer with ControlNet and EtherNet/IP.

• offers diagnostics for improved data collection and fault detection.

• requires less wiring than traditional, hardwired systems.

54


Personal Computer

CompactLogix System with

1769-ADN DeviceNet

Adapter


Chapter 4

You can use a linking device as a:

• gateway to connect information.

• control-level network to device-level network for programming, configuration, control or data collection.

• router/bridge to connect the EtherNet/IP or ControlNet network to the

DeviceNet network.

Figure 7 - CompactLogix Linking Device Overview

ControlLogix Controller with

1756-ENBT Module

EtherNet/IP Network

FLEX Adapter and I/O

CompactLogix Controller with

Built-in EtherNet/IP

Communication Port

1788-EN2DN

Linking Device

DeviceNet Network

Sensor

Motor

Starter

Input/Output

Devices

PowerFlex AC

Drive

Indicator

Lights

Pushbutton

Cluster

Bar Code

Scanner

Serial Communication

CompactLogix controllers have a built-in RS-232 port.

• 1769-L32C, -L32E, -L35CR, and -L35E CompactLogix controllers have one built-in RS-232 port. By default, that port is channel 0 on these controllers.

• The 1769-L31 CompactLogix controller has two RS-232 ports. One port only allows DF1 protocol only. The second port accepts DF1 and ASCII protocol.

IMPORTANT

Limit the length of serial (RS-232) cables to 15.2 m (50 ft).

You can configure the serial port of the controller for several modes.


55

Chapter 4


Table 10 - CompactLogix Serial Port Configurations

Mode

DF1 Point-to-Point

DF1 Master

DF1 Slave

DF1 Radio Modem

User (channel 0 only)

DH-485

Modes

Communicate between the controller and one other DF1-protocol-compatible device.

This is the default system mode. Default parameters are:

• Baud Rate: 19,200

• Data Bits: 8

• Parity: None

• Stop Bits: 1

• Control Line: No Handshake

• RTS send Delay: 0

• RTS Off Delay: 0

This mode is typically used to program the controller through its serial port.

Control polling and message transmission between the master and slave nodes.

• The master/slave network includes one controller configured as the master node and as many as 254 slave nodes. Link slave nodes using modems or line drivers.

• A master/slave network can have node numbers from 0...254. Each node must have a unique node address. Also, at least 2 nodes must exist to define your link as a network (1 master and 1 slave station are the two nodes).

Use a controller as a slave station in a master/slave serial communication network.

• When there are multiple slave stations on the network, link slave stations using modems or line drivers to the master. When you have a single slave station on the network, you do not need a modem to connect the slave station to the master. You can configure the control parameters for no handshaking. You can connect 2...255 nodes to a single link. In DF1 slave mode, a controller uses DF1 half-duplex protocol.

• One node is designated as the master and it controls who has access to the link. All the other nodes are slave stations and must wait for permission from the master before transmitting.

• Compatible with SLC500 and MicroLogix1500 controllers.

• This mode supports master and slave, and store and forward modes.

Communicate with ASCII devices.

This requires your program to use ASCII instructions to transmit data to and from ASCII device.

• Communicate with other DH-485 devices.

• This multi-master, token-passing network allows programming and peer-to-peer messaging.

56


Baud Rate Selector Switch

Port 1: DB-9 RS-232, DTE


Chapter 4

Configure an Isolator

Channel 0 on the CompactLogix controllers is fully isolated and does not need a separate isolation device. Channel 1 on the 1769-L31 controller is not an isolated serial port. To configure an isolator, perform this procedure.

1. Determine whether you need an isolator.

If you connect channel 1 of the 1769-L31 controller to a modem or an

ASCII device, consider installing an isolator between the controller and modem or ASCII device. An isolator is also recommended when connecting the controller directly to a programming workstation.

One possible isolator is the 1761-NET-AIC interface converter.

Port 2: Mini-DIN 8 RS-232

DC Power Source Selector Switch

Terminals for External 24V DC

Power Supply


57

Chapter 4


Are you using an isolator?

No

Yes

2. Select the appropriate cable.

Then use this cable

The 1756-CP3 cable attaches the controller directly to the controller.

1 CD

2 RDX

3 TXD

4 DTR

COMMON

6 DSR

7 RTS

8 CTS

1 CD

2 RDX

3 TXD

4 DTR

COMMON

6 DSR

7 RTS

8 CTS

9 9

If you make your own cable, it must be shielded, and the shields must be tied to the metal shell (that surrounds the pins) on both ends of the cable.

You can also use a 1747-CP3 cable from the SLC product family. This cable has a taller right-angle connector housing than that of the 1756-CP3 cable.

The 1761-CBL-AP00 cable (right-angle connector to controller) or the 1761-CBL-PM02 cable (straight connector to the controller) attaches the controller to port 2 on the 1761-NET-AIC isolator. The mini-DIN connector is not commercially available, so you cannot make this cable.

1

7

6

2

3

6 7 8

8

9

5

4

3

4

1 2

5

DB-9 Right-angle or Straight Cable End 8-pin, Mini-DIN Cable End

5

6

3

4

Pin

1

2

7

8

9

RTS

CTS

NA

DB-9 End

DCD

RxD

TxD

DTR

Ground

DSR

RTS

CTS

NA

Mini-DIN End

DCD

RxD

TxD

DTR

Ground

DSR

3. Connect the appropriate cable to the serial port.

58



Chapter 4

Communicate with DF1 Devices

You can configure the controller as a master or slave on a serial communication network. Use serial communication when:

• the system contains three or more stations.

• communication occur regularly and require leased-line, radio, or power-line modem.

ATTENTION: Only the 1769-L31 controller has more than one RS-232 port. All other 1769 controllers are limited to one RS-232 port.

EtherNet/IP

RS-232

RS-232

RS-232

RS-232

Modem

Modem

Modem

To configure the controller for DF1 communication, perform this procedure.

1. In RSLogix 5000 programming software, right-click your controller and select Properties.


59

Chapter 4


The Controller Properties dialog box appears.

2. Click the Serial Port tab.

3. From the Mode pull-down menu, choose System.

4. Specify communication settings.

5. Click the System Protocol tab.

6. From the Protocol pull-down menu, choose a DF1 protocol.

7. Specify DF1 settings.

60



Chapter 4

IMPORTANT

DF1 Radio Modem Support

Your ControlLogix controller includes a driver that lets it to communicate over the DF1 Radio Modem protocol. This driver implements a protocol, optimized for use with radio modem networks, that is a hybrid between DF1 full-duplex protocol and DF1 half-duplex protocol, and therefore is not compatible with either of these protocols.

The DF1 radio modem driver should be used only among devices that support and are configured for the DF1 radio modem protocol.

Additionally, there are some radio modem network configurations that will not work with the

DF1 radio modem driver. In these configurations, continue to use DF1 half-duplex protocol.

Like DF1 full-duplex protocol, DF1 radio modem lets any node to connect to any other node at any time (if the radio modem network supports full-duplex data port buffering and radio transmission collision avoidance). Like DF1 half-duplex protocol, a node ignores any packets received that have a destination address other than its own, with the exception of broadcast packets and pass-through packets.

Unlike either DF1 full-duplex or DF1 half-duplex protocols, DF1 radio modem protocol does not include ACKs, NAKs, ENQs, or poll packets. Data integrity is assured by the CRC checksum.

Using the DF1 Radio Modem Driver

The DF1 radio modem driver can be configured as the system mode driver by using RSLogix 5000 programming software, version 17 or later.

To configure the controller for DF1 Radio Modem communication, perform this procedure.


61

Chapter 4


1. In the Controller Organizer of RSLogix 5000 programming software, right-click your controller and select Properties.



62

3. From the Protocol pull-down menu, choose DF1 Radio Modem.


Setting

Station Address

Error Detection

Enable Store and Forward


Chapter 4

4. Specify DF1 Radio Modem system protocol settings.

Description

Specifies the node address of the controller on the serial network. Select a number 1… 254 decimal, inclusive.

To optimize network performance, assign node addresses in sequential order. Initiators, such as personal computers, should be assigned the lowest address numbers to minimize the time required to initialize the network.

Click one of the radio buttons to specify the error detection scheme used for all messages.

• BCC - the processor sends and accepts messages that end with a BCC byte.

• CRC - the processor sends and accepts messages with a 2-byte CRC.

Check the Enable Store and Forward checkbox if you want to enable the store and forward functionality. When enabled, the destination address of any received message is compared to the Store and Forward tag table. If there is a match, the message is then forwarded

(re-broadcasted) from the port.

From the Store and Forward Tag pull-down menu, choose an integer (INT[16]) tag.

Each bit represents a station address. If this controller reads a message destined for a station that has its bit set in this table, it forwards the message.

Also note, the Enable Store and Forward function is usable only if the controller is connected to the master radio modem.

5. Click OK.

Advantage of Using DF1 Radio Modem Protocol

The primary advantage of using DF1 radio modem protocol for radio modem networks is in 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). This minimizes the number of times the radios need to key-up to transmit, which maximizes radio life and minimizes radio power consumption. In contrast, DF1 half-duplex protocol requires five transmissions for the DF1 master to complete a read/write transaction with a DF1 slave - three by the master and two by the slave.

The DF1 radio modem driver can be used in a pseudo master/slave mode with any radio modems, as long as the designated master node is the only node initiating MSG instructions, and as long as only one MSG instruction is triggered at a time.

For modern serial radio modems that support full-duplex data port buffering and radio transmission collision avoidance, the DF1 radio modem driver can be used to set up a masterless peer-to-peer radio network. In a peer-to-peer radio network, any node can initiate communication to any other node at any time, as long as all of the nodes are within radio range so that they receive each other’s transmissions.


63

Chapter 4


DF1 Radio Modem System Limitations

The following questions need to be answered to determine if you can implement the new DF1 radio modem driver in your radio modem network.

• If all of the devices on the network are ControlLogix controllers, you must configure them with the DF1 radio modem driver by using RSLogix 5000 programming software, version 17 or later. If not, then make sure that all of the nodes can support the DF1 radio modem protocol.

• If each node receives the radio transmissions of every other node, being both within radio transmission/reception range and on a common receiving frequency (either via a Simplex radio mode or via a single, common, full-duplex repeater) the radio modems must handle full-duplex data port buffering and radio transmission collision avoidance.

If this is the case, you can take full advantage of the peer-to-peer message initiation capability in every node (for example, the ladder logic in any node can trigger a MSG instruction to any other node at any time).

If not all modems can handle full-duplex data port buffering and radio transmission collision avoidance, you may still be able to use the DF1 radio modem driver, but only if you limit MSG instruction initiation to a single master node whose transmission can be received by every other node.

• If not all nodes receive the radio transmission of every other node, you may still be able to use the DF1 radio modem driver, but only if you limit MSG instruction initiation to the node connected to the master radio modem whose transmissions can be received by every other radio modem in the network.

• You can take advantage of the ControlLogix controller channel-to-channel pass-through to remotely program the other nodes using RSLinx and

RSLogix 5000 programming software running on a personal computer connected to a local ControlLogix controller via DH-485, DH+, or

Ethernet.

Communicate with ASCII Devices

You can use the serial port to interface with ASCII devices when the controller is configured for user mode. For example, you can use the serial port to:

• read ASCII characters from a weigh scale module or bar code reader.

• send and receive messages from an ASCII triggered device, such as a

MessageView terminal.

64



Chapter 4

Figure 8 - ASCII Device Serial Communication

Connection from the Controller’s Serial Port to the ASCII Device

To configure the controller for ASCII communication, perform this procedure.

1. In RSLogix 5000 programming software, right-click your controller and select Properties.



3. From the Mode pull-down menu, choose User.



65

Chapter 4


5. Click the User Protocol tab.

66

ARD

ARL

AWA

AWT

AHL

6. From the Protocol pull-down menu, choose ASCII.

7. Specify ASCII settings.

The controller supports several instructions to manipulate ASCII characters.

The instructions are available in ladder diagram (LD) and structured text (ST).

Read and Write ASCII Characters

Instruction Code

ABL

ACB

ACL

Description

Determine when the buffer contains termination characters

Count the characters in the buffer

Clear the buffer

Clear out ASCII Serial Port instructions that are currently executing or are in the queue

Obtain the status of the serial port control lines

Turn on or off the DTR signal

Turn on or off the RTS signal

Read a fixed number of characters

Read a varying number of characters, up to and including the first set of termination characters

Send characters and automatically append one or two additional characters to mark the end of the data

Send characters

Create and Modify Strings of ASCII Characters


CONCAT

DELETE

FIND

INSERT

MID

Description

Add characters to the end of a string

Delete characters from a string

Determine the starting character of a substring

Insert characters into a string

Extract characters from a string



Chapter 4

Convert Data to or from ASCII Characters


STOD

STOR

DTOS

RTOS

UPPER

LOWER

Description

Convert the ASCII representation of an integer value to a SINT, INT, DINT, or REAL value

Convert the ASCII representation of a floating-point value to a REAL value

Convert a SINT, INT, DINT, or REAL value to a string of ASCII characters

Convert a REAL value to a string of ASCII characters

Convert the letters in a string of ASCII characters to upper case

Convert the letters in a string of ASCII characters to lower case

Modbus Support

To use Logix5000 controllers on Modbus, connect the controllers through the serial port and execute specific ladder logic routines.

A sample controller project is available with RSLogix 5000 Enterprise programming software.

Broadcast Messages over a Serial Port

You can broadcast messages over a serial port connection from a master controller to all of its slave controllers by using several communication protocols. Those protocols are the following:

• DF1 Master

• DF1 Radio Modem

• DF1 Slave

Broadcasting over a serial port is achieved using the ‘message’ tag. Because messages are sent to receiving controllers, only the ‘write’ type messages can be used for broadcasting.

The broadcast feature can be set up by using ladder logic programming software or Structured Text programming software.

The broadcast feature can also be set by modifying the path value of a message tag in the tag editor.

For this example, Ladder Logic programming software will be used.


67

Chapter 4


Step 1: Set Broadcast-Controller Properties

First, set the System Protocol by following these steps.

1. In the Controller Organizer, right-click on the controller and choose

Properties.

2. In the Controller Properties dialog box, from the System Protocol tab, choose the settings for the controller, then choose OK.

Field

Station Address

Transmit Retries

ACK Timeout

Slave Poll Timeout

Reply Message Wait

Polling Mode

EOT Suppression

3

50

DF-1 Master Protocol

Controller station address number

DF-1 Slave Protocol


3

N/A

N/A

5

3000

N/A

Message: polls the slave by using the Message instruction

Slave: initiates messages for slave-to-slave broadcast.

Standard: schedules polling for the slave.

N/A

N/A

Disable

N/A

N/A

N/A

DF-1 Radio Modem Protocol


N/A

N/A

N/A

68


Field

Error Detection

Duplicate Detection

Enable Store and Forward


Chapter 4

DF-1 Master Protocol

BCC

Enabled

N/A

DF-1 Slave Protocol

BCC

Enabled

N/A

DF-1 Radio Modem Protocol

BCC

N/A

Choose enable if you want to use the store and forward tag.

The last bit of the INT[16] Enable Store and

Forward array must be ’enabled.’ For example, say you create an INT[16] tag named EnableSandF. Then

EnableSandF[15].15 must be set to 1 for broadcast to work on radio modem.

Step 2: Set Broadcast - Create Controller Scope Message Tag

Next, create a Message tag by following these steps.

1. In the Controller Organizer, right-click on the Controller Tags folder and choose New Tag.

The new tag must be a ‘message’ tag.

2. Name the tag and select the Data Type ‘Message’, then choose OK.

The Message tag in the Controller Scope’s Controller Tags folder will look similar to the following.


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Chapter 4


Step 3: Ladder Logic Programming Software

Then, to set broadcasting over a serial port, follow these steps.

1. In the Controller Organizer, from the Tasks folder, choose Main Routine to display the ladder logic programming software interface.

2. Open a MSG instruction from the Input/Output tab.

3. Double-click in the Message Control field to enable the pull-down menu and select the tag you created.

4. Launch the View Configuration dialog box.

5. In the Message Configuration dialog box, from the Configuration tab, select the message type from the Message Type field.

70

Valid ‘Write’ Message Types include the following:

• CIP Generic

• CIP Data Table Write

• PLC2 Unprotected Write

• PLC3 Typed Write

• PLC3 Word Range Write

• PLC5 Typed Write

• PLC5 Word Range Write

• SLC Typed Write

6. Fill in any other fields needed.



Chapter 4

7. From the Communication tab, select the Broadcast Radio button and the

Channel from the pull-down, then choose OK.

ATTENTION: When using structured text programming software, broadcast over serial is set by typing MSG(aMsg) and right-clicking on a

MSG to display the Message Configuration dialog box.


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Chapter 4


DH-485 Network

Communication

For DH-485 communication, use the controller’s serial port.

However, with a CompactLogix controller, we recommend that you use NetLinx networks, such as EtherNet/IP, ControlNet, or DeviceNet, because excessive traffic on a DH-485 network may make it impractical to connect to a controller with RSLogix 5000 programming software.

IMPORTANT

If your application uses connections to DH-485 networks, select built-in serial ports.

The DH-485 protocol uses RS-485 half-duplex as its physical interface. RS-485 is a definition of electrical characteristics, not a protocol. You can configure the

CompactLogix controller’s RS-232 port to act as a DH-485 interface. By using a

1761-NET-AIC converter and the appropriate RS-232 cable (1756-CP3 or

1747-CP3), a CompactLogix controller can send and receive data on a DH-485 network.

Figure 9 - CompactLogix DH-485 Communication Overview


1747-CP3 Cable or

1761-CBL-AC00 Cable

(port 1)

Connection from CompactLogix

Controller to Port 1 or Port 2

1761-CBL-AP00 Cable or

1761-CBL-PM02 Cable

1761-NET-AIC+

Converter

1747-CP3 Cable or

1761-CBL-AC00 Cable

DH-485 Network

1747-AIC Converter

72

SLC 5/03 Controller

On the DH-485 network, the CompactLogix controller can send and receive messages to and from other controllers.

IMPORTANT

A DH-485 network consists of multiple cable segments. Limit the total length of all the segments to 1219 m (4000 ft).

For the controller to operate on a DH-485 network, you need a 1761-NET-AIC interface converter for each controller you want to put on the DH-485 network.

You can have two controllers for each 1761-NET-AIC converter, but you need a different cable for each controller.



Chapter 4

To establish DH-485 communication, perform this procedure.

1. Connect the serial port of the controller to either port 1 or port 2 of the

1761-NET-AIC converter.

2. Use the RS-485 port to connect the converter to the DH-485 network.

The cable you use to connect the controller depends on the port you use on the 1761-NET-AIC converter.

Connection

Port 1

DB-9 RS-232, DTE connection

Port 2 mini-DIN 8 RS-232 connection

Required Cable

1747-CP3 or

1761-CBL-AC00

1761-CBL-AP00 or

1761-CBL-PM02

3. In RSLogix 5000 programming software, right-click on your controller and choose Properties.

The Controller Properties dialog appears.


5. From the Mode pull-down menu, choose System.


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Chapter 4



IMPORTANT

The baud rate specifies the communication rate for the

DH-485 port. All devices on the same DH-485 network must be configured for the same baud rate. Select 9600 or

19200 KB.


8. From the Protocol pull-down menu, choose DH485.

9. Specify DH-485 settings.

10. From the Protocol pull-down menu, choose DF1 Radio.

Table 11 - System Protocol Specifications

Characteristic

Station Address

Token Hold Factor

Maximum Station

Address

Description

Specifies the node address of the controller on the DH-485 network. Select a number 1...31 decimal, inclusive.

To optimize network performance, assign node addresses in sequential order. Initiators, such as personal computers, should be assigned the lowest address numbers to minimize the time required to initialize the network.

Number of transmissions plus retries that a node holding a token can send onto the data link each time it receives the token. Enter a value between 1...4. The default is 1.

Specifies the maximum node address of all the devices on the DH-485 network. Select a number 1...31 decimal, inclusive.

To optimize network performance, make sure:

• the maximum node address is the highest node number being used on the network.

• that all the devices on the same DH-485 network have the same maximum node address.

74


Communicate over Networks. Allen-Bradley 1769-L35CR CompactLogix 5335CR, 1769-L31 CompactLogix 5331, 1769-L32C CompactLogix 5332C, 1769 CompactLogix, 1769-L35E CompactLogix 5335E, 1769-L32E CompactLogix 5332E

Communicate over Networks

EtherNet/IP Network

Communication

Connections over an EtherNet/IP Network

ControlNet Network

Communication

Connections over ControlNet

DeviceNet Communication

Serial Communication

Configure an Isolator

Communicate with DF1 Devices

DF1 Radio Modem Support

Using the DF1 Radio Modem Driver

Advantage of Using DF1 Radio Modem Protocol

DF1 Radio Modem System Limitations

Communicate with ASCII Devices

Read and Write ASCII Characters

Create and Modify Strings of ASCII Characters

Convert Data to or from ASCII Characters

Modbus Support

Broadcast Messages over a Serial Port

Step 1: Set Broadcast-Controller Properties

Step 2: Set Broadcast - Create Controller Scope Message Tag

Step 3: Ladder Logic Programming Software

DH-485 Network

Communication

Key Features

Related manuals

Frequently Answers and Questions

What is the processor speed of the 1769-L35CR?

How much memory does the 1769-L35CR have?

What communication ports are built into the 1769-L35CR?

Table of contents

Communicate over Networks. Allen-Bradley 1769-L35CR CompactLogix 5335CR, 1769-L31 CompactLogix 5331, 1769-L32C CompactLogix 5332C, 1769 CompactLogix, 1769-L35E CompactLogix 5335E, 1769-L32E CompactLogix 5332E