EtherNet/IP Socket Interface Application Technique, ENET-AT002E-EN-P

Application Technique

Original Instructions

EtherNet/IP Socket Interface

2 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

EtherNet/IP Socket Interface Application Technique

Summary of Changes

This publication contains the following new or updated information. This list includes substantive updates only and is not intended to reflect

all changes.

Topic Page

Added Secure Socket Object section 13

Revised instructions for communicating with a socket object via an MSG instruction 15, 16

Added error codes 38, 39

Added Exposing TLS Errors section 40

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 3

Table of Contents

Summary of Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

About This Publication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Download Firmware, AOP, EDS, and Other Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Chapter 1

Socket Interface Architecture

Socket Interface Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Number and Type of Sockets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Typical Sequence of Transactions for a TCP Client . . . . . . . . . . . . . . . . . . . . . . . . 9

Typical Sequence of Transactions for a TCP Server. . . . . . . . . . . . . . . . . . . . . . . . 10

Typical Sequence of Transactions for UDP without OpenConnection . . . . . . . . . . 11

Typical Sequence of Transactions for UDP with OpenConnection. . . . . . . . . . . . . 12

Secure Socket Object. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Communicate with the Socket Object via an MSG Instruction. . . . . . . . . . . . . . . . . . . . 15

Service Timeouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

MSG Instruction Timeouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Socket Instance Timeouts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Disable the Socket Object with an MSG Instruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Programming Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

TCP Connection Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

ControlLogix Redundancy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

EtherNet/IP Module Reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Change Controller Mode between Run and Program. . . . . . . . . . . . . . . . . . . . . . . 20

Application Messages and TCP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Application Messages and Inhibited Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Partial Reads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Partial Writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Performance Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Chapter 2

Socket Object Services

Socket Create. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

OpenConnection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

AcceptConnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Table of Contents

ReadSocket. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

WriteSocket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

DeleteSocket . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

DeleteAllSockets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

ClearLog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

JoinMulticastAddress. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

DropMulticastAddress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

MSG Source Element. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

MSG Source Length. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

MSG Destination Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Chapter 3

Socket Attributes

Socket Class Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Socket Instance Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Chapter 4

Troubleshoot Socket

Applications

Diagnostic Webpages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Debugging Tips. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Error Codes for Socket Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Exposing TLS Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Knowledgebase Articles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Additional Resources

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 5

Preface

About This Publication

This publication describes the socket interface that you can use to program MSG instructions to communicate between a Logix 5000™

controller via an EtherNet/IP™ module and Ethernet devices that do not support the EtherNet/IP application protocol, such as barcode

scanners, RFID readers, or other standard Ethernet devices.

Download Firmware, AOP, EDS, and Other Files

Download firmware, associated files (such as AOP, EDS, and DTM), and access product release notes from the Product Compatibility and

Download Center at rok.auto/pcdc.

6 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 7

Chapter 1

Socket Interface Architecture

The socket interface lets a Logix 5000® controller communicate with Ethernet devices that do not support the EtherNet/IP™ protocol. Such

devices include barcode scanners, RFID readers, or other standard Ethernet devices.

Socket services are available with these modules:

• ControlLogix® 5580 and GuardLogix® 5580 controllers

• CompactLogix™ 5380 and Compact GuardLogix 5380 controllers

• CompactLogix 5370 and Compact GuardLogix 5370 controllers

• CompactLogix 5480 controllers

• 1756-EN2x, 1756-EN3TR, and 1756-EN4TR EtherNet/IP communication modules

• 1756-EWEB and 1768-EWEB EtherNet/IP web server modules

Before you use the socket interface, make sure that you are familiar with these concepts:

• Basic TCP/IP, UDP, and socket programming concepts

• How to write socket programs in a programming language, such as C or Visual Basic

• How to use diagnostic tools, such as a network sniffer

• The application protocols of the devices and applications with which the Logix 5000 controller communicates

• How to write ladder logic or Structured Text for a Logix 5000 controller

Socket Interface Architecture

The socket interface is implemented via the socket object in the EtherNet/IP module or directly in the controller via the front port.

Logix 5000 controller programs communicate with the socket object via MSG instructions. MSG requests to the socket object are similar to

socket API calls in most computer operating systems. The socket object services let you open connections, accept incoming connections,

send data, and receive data.

To communicate with another device, you must understand the application protocol of the device. The EtherNet/IP module has no

application protocol knowledge. The module makes only the socket services available to programs in Logix 5000 controllers.

Number and Type of Sockets

The following table shows the number of supported socket instances.

IMPORTANT MicroLogix™ 1400 controllers also support socket capability, but the information in this document does not apply to

those products. For details on those products, see the MicroLogix 1400 Programmable Controllers Reference Manual,

publication 1766-RM001D

32 Socket Instances 20 Socket Instances

• ControlLogix 5580 controllers

• GuardLogix 5580 controllers

• CompactLogix 5480 controllers

• CompactLogix 5380 controllers

• Compact GuardLogix 5380 controllers

• CompactLogix 5370 controllers

• Compact GuardLogix 5370 controllers

• 1756-EN2x EtherNet/IP communication modules

• 1756-EN3TR EtherNet/IP communication module

• 1756-EN4TR EtherNet/IP communication module

• 1756-EWEB EtherNet/IP web server module

• 1768-EWEB EtherNet/IP web server module

8 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 1 Socket Interface Architecture

Each instance can be one of these types:

• UDP socket—Sends and receives UDP datagrams.

• TCP client socket—The Logix 5000 program initiates the connection.

• TCP server socket—Another device initiates the connection to the Logix 5000 program.

• TCP listen socket—Listens on a specified port number for incoming connections.

These options are available for UDP and TCP send and receive services.

You must have a listen socket for each TCP port number that accepts connections. Multiple TCP server sockets can share a listen socket if

the connections are made to the same port number.

You can partition the available socket instances between UDP and TCP sockets in these ways:

• Use all instances for client TCP connections.

• Use one instance to listen for incoming TCP connections and then accept the remaining connections from other devices.

• Perform both TCP client and server operations.

• Perform both TCP and UDP operations.

The following table lists the available socket services.

Once you open a connection on a client socket instance, you cannot use the same socket instance to accept incoming connections. Similarly,

if you accept connections on a socket instance, you cannot then use the instance to open outgoing connections. This behavior is consistent

with standard socket API behavior.

Type Communication Send (Write) Receive (Read)

UDP

Unicast Yes Yes

Multicast Yes Yes

Broadcast Yes Yes

TCP

Unicast Yes Yes

Multicast — —

Broadcast — —

Socket Service Socket Instance Page

Socket Create Server or client 23

OpenConnection Client 25

AcceptConnection

If you issue an AcceptConnection service, the instance is a listen type.

If the AcceptConnection service returns an instance as a result of an incoming connection

request, the socket instance is a server type.

ReadSocket Server or client 27

WriteSocket Server or client 29

DeleteSocket Server or client 30

DeleteAllSockets Server or client 31

ClearLog Server or client 32

JoinMulticastAddress Server or client 32

DropMulticastAddress Server or client 33

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 9

Chapter 1 Socket Interface Architecture

Typical Sequence of Transactions for a TCP Client

The following diagram shows a typical sequence of socket interface transactions with the Logix 5000 controller that acts as a TCP client.

Each transaction between the Logix 5000 controller and the EtherNet/IP module is a message (MSG) instruction.

In the following example, the Logix 5000 controller sends data to a device, and then the device sends a response. This sequence of

transactions is typical. Depending on the application protocol, the device can instead send data to the Logix 5000 controller once the

connection is open.

Also, each write transaction does not require an application response or acknowledgment. The application protocol determines the exact

sequence of application transactions.

Controller

EtherNet/IP Module

192.168.1.10

Device

192.168.1.11

Accept Connection

Receive Data

Send Data

Open TCP

Connection

Data = abc

Data = xyz

The response is returned to the controller as

soon as the data is sent.

Create

Socket

Create Socket Response

Instance = 102

OpenConnection

"192.168.1.11?Port=49200"

OpenConnection Response

Write Data = abc

Write Response

Read

Read Response Data = xyz

10 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 1 Socket Interface Architecture

Typical Sequence of Transactions for a TCP Server

The following diagram shows a typical sequence of socket interface transactions with the Logix 5000 controller as a TCP server. Each

transaction between the Logix 5000 controller and EtherNet/IP module is an MSG instruction.

The following is a typical sequence of transactions. The exact sequence to send and receive data depends on the application protocol.

Controller

EtherNet/IP Module

192.168.1.10

Device

192.168.1.11

Open Connection

Send Data

Receive Data

Open TCP Connection

Port = 49100

Data = abc

Data = xyz

The response is returned to the

controller as soon as the data is sent.

Create Socket

Port = 49100

Create Socket Response

Instance = 102

AcceptConnection

Write

Data = xyz

Write Response

Read

Read Response

Data = abc

AcceptConnection Response

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 11

Chapter 1 Socket Interface Architecture

Typical Sequence of Transactions for UDP without OpenConnection

The following diagram shows a typical sequence of socket interface transactions for UDP communication without using the OpenConnection

service to specify the destination address. In this case, the Logix 5000 controller specifies the destination for each datagram and receives

the address from the sender along with each datagram it receives. Each transaction between the Logix 5000 controller and the EtherNet/IP

module is an MSG instruction.

This example shows the Logix 5000 controller sending data to a device, and then the device sending a response. This sequence of

transactions is atypical. Depending on the application protocol, the device could instead initiate sending data to the Logix 5000 controller.

Also, each Write transaction does not require an application response or acknowledgment. The application protocol determines the exact

sequence of application transactions.

Controller

EtherNet/IP Module

192.168.1.10

Device

192.168.1.11

Create Socket

Port=49100

Create Socket

Response Instance =

102

Write

192.168.1.11?Port=49200

Data = abc

Write Response

Read

Read Response

192.168.1.11?Port=49200

Data = xyz

Send Data to

192.168.1.10, Port 49100

Receive Data from Port 49200

Data = abc

Data = xyz

The response is returned to the controller as

soon as the data is sent.

12 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 1 Socket Interface Architecture

Typical Sequence of Transactions for UDP with OpenConnection

The following diagram shows a typical sequence of socket interface transactions for UDP communication when using the OpenConnection

service to specify the destination address. Each transaction between the Logix 5000 controller and the EtherNet/IP module is an MSG

instruction.

The following is a typical sequence of transactions. The exact sequence of sending and receiving data depends on the application protocol.

Controller

EtherNet/IP Module

192.168.1.10

Device

192.168.1.11

Create

Socket

Port=49100

Create Socket Response

Instance = 102

Open Connection

192.168.1.11?Port=49200

Open Connection Response

Read

Read Response

192.168.1.11?Port=49200

Data = xyz

Write

Data = abc

Write Response

Data = abc

Data = xyz

The response is returned to the controller as

soon as the data is sent.

Send Data To

192.168.1.10, Port 49100

Receive Data from Port 49200

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 13

Chapter 1 Socket Interface Architecture

Secure Socket Object

The following devices support Transport Layer Security (TLS) for a secure socket object.

The TLS support has these considerations:

• TCP/TLS version 1.2 only; UDP/DTLS not supported

• Client only; server not supported

• Server authentication supported; client authentication not supported

• Secure socket object and CIP Security™ cannot be used at the same time

• Connections with multiple servers are not supported

• No Certificate Revocation List support

• No Subject Alternative Name support

• On multi-port devices (ControlLogix 5380 in dual IP mode), the same security is applied to both ports

TLS support is enabled by putting server certificates on the SD card. Certificates are loaded at startup only. The server certificates are

expected to be stored in the following files in PEM format:

• certs/ca.pem—A CA certificate signed by some trusted certificate authority

• certs/trustedcert.pem—A trusted peer certificate to be compared against the certificate sent during the TLS handshake

The following rules apply to the TLS protocol:

• If at least one certificate is present in the prescribed location and prescribed filename, TLS is applied to the socket object.

• If the SD card is not present, disabled, or neither of the certificates are present, then the socket object behaves as in previous

releases and no security is applied.

Once the encryption is enabled, it cannot be disabled without restarting the device.

Supported cipher suites include the following:

• TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 (0xc027)

• TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (0xc02f)

• TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (0xc030)

• TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 (0xc028)

• TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 (0xc023)

• TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 (0xc02b)

• TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 (0xc02c)

• TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 (0xc024)

IMPORTANT TLS for a secure socket object is not supported in ControlLogix redundancy or 1756-EN4TR redundant adapter mode.

Controllers and Communication Modules First Available in Firmware Revision

CompactLogix 5380 35.011 and later

Compact GuardLogix 5380 SIL 2 35.011 and later

Compact GuardLogix 5380 SIL 3 35.011 and later

CompactLogix 5380 Process 35.011 and later

ControlLogix 5580 35.011 and later

GuardLogix 5580 35.011 and later

ControlLogix 5580 Process 35.011 and later

1756-EN4TR, 1756-EN4TRK, 1756-EN4TRXT 5.001 and later

14 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 1 Socket Interface Architecture

When encryption is enabled, the overall socket object performance is reduced. The impact depends on many factors, such as payload size,

number of sockets involved, and the cipher suite used.

Table 1

shows the maximum transfer rate when a socket object instance is running as a client connected to the HTTPS REST API server.

Simultaneously, the module handles multiple class 3 connections and data exchange with the server. The HTTP values apply to non-TLS

communications, while the HTTPS values apply with cipher suite TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 applied.

For information on how to develop your application to access the HTTP REST API and implement HTTPS via the socket interface with TLS, see

documentation for these objects in the Common Application Libraries available in the Product Compatibility and Download Center at

rok.auto/pcdc

• raC_Impl_HTTPClient

• raC_Impl_HTTPCmdGET

• raC_Impl_HTTPCmdPOST

• raC_Impl_HTTPCmdPUT

Table 1 - Secure Socket Object Transfer Rates, Max

1756-EN4TR

ControlLogix 5580

CompactLogix 5380

Payload: 60 kB

Request: GET

HTTPS 140 kB/sec 270 kB/sec

HTTP 280 kB/sec 660 kB/sec

Payload: 60 kB

Request: PUT/POST

HTTPS 180 kB/sec 380 kB/sec

HTTP 290 kB/sec 800 kB/sec

Payload: 1 kB

Request: GET

HTTPS 12 kB/sec 20 kB/sec

HTTP 14 kB/sec 30 kB/sec

Payload: 1 kB

Request: PUT/POST

HTTPS 19 kB/sec 30 kB/sec

HTTP 21 kB/sec 50 kB/sec

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Chapter 1 Socket Interface Architecture

Communicate with the Socket Object via an MSG Instruction

In the Logix Designer application, use a CIP™ Generic MSG instruction to request socket services.

On the Configuration tab for the MSG instruction, configure the parameters as described in Table 2

Table 2 - Configuration Tab

Field Description

Message Type Choose CIP Generic.

Service Type

Choose a socket service type. The software automatically completes the Service Code and Class fields.

Choose Get Attributes Single or Set Attributes Single when getting or setting a socket object attribute. For more information, see Socket

Attributes on page 35.

Service Code Enter the unique service code that corresponds to the socket service you chose in the Service Type field.

Class Enter 342 (hexadecimal) for the socket object.

Instance

Enter one of these values:

• 0 for Socket Create, Delete All Sockets, or ClearLog services

• Instance number that is returned by Socket Create for other services

Use a relay ladder instruction or Structured Text statement to move the returned instance number from a Socket Create service into the

Instance member of an MSG instruction.

Attribute Enter an attribute value only when getting or setting an attribute, but not when using other services.

Source Element

Choose the tag that contains the request parameters for the socket service. To define the request parameters, create a user-defined

data type for the tag.

Source Length Enter the length of the source element.

Destination Element

Choose the tag that contains the response data that the socket service returns. To define the response data, create a user-defined data

type for the tag.

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On the Communication tab for the MSG instruction, configure the parameters that are described in Table 3.

The maximum amount of data you can send or receive depends on how you configure the MSG instruction, as shown in Table 4

. The size of

the data excludes the parameters in the ReadSocket and WriteSocket services.

If an MSG requests more than the maximum packet size (standard or large), the module can return a failure status and the MSG instruction

can set the .ER bit:

• For TCP sockets, if the application data is larger than the maximum size, you can issue multiple ReadSocket or WriteSocket services

to receive or send the entire application message.

• For UDP sockets, the size of application data cannot exceed the maximum sizes for the ReadSocket and WriteSocket services.

IMPORTANT If you use the front Ethernet port on a controller, you must use unconnected MSG instructions. For unconnected MSG

instructions, you must clear the Connected checkbox on the Communication tab.

Table 3 - Communication Tab

Field Description

Path

Enter the communication path to the EtherNet/IP module.

• For all communication modules, the path is 1, x. where x is the slot number of the communication module.

• For ControlLogix 5580 controllers, if the front Ethernet port is used, the path is 1, x where x is the slot number of the ControlLogix controller.

• For all supported CompactLogix controllers, the path is 1, 0.

When using the front Ethernet port on a controller with firmware revision 28.011 or later, you can also use a path of ‘THIS’.

Large Connection

To send large messages via an EtherNet/IP module on the backplane when using a ControlLogix 5560, 5570, or 5580 controller, you can check the

Large Connection checkbox. Large connections are only available with connected MSG instructions. For information about how to use the Connected

or Cache Connections options, refer to the Logix 5000 Controllers Messages Programming Manual, publication 1756-PM012

IMPORTANT: To use controller memory efficiently, use large connections only for ReadSocket or WriteSocket services that require more than the

standard connection size, as shown in Table 4

To avoid errors, be sure that you use unconnected MSG instructions by clearing the Connected checkbox in these scenarios:

• You are using the front Ethernet port on a ControlLogix 5580, CompactLogix 5380, or CompactLogix 5480 controller. Large connections are enabled

by default on these controllers.

• You are using a CompactLogix 5370 controller. Large connections are not supported on these controllers.

Table 4 - Maximum Packet Sizes

Service Unconnected Size Standard Connection Size Large Connection Size

ReadSocket 484 bytes 484 bytes 3984 bytes

WriteSocket 462 bytes 472 bytes 3972 bytes

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Chapter 1 Socket Interface Architecture

Service Timeouts

You must specify a timeout parameter in milliseconds for any service that does not always complete immediately, such as OpenConnection,

AcceptConnection, ReadSocket, and WriteSocket services. The timeout tells the socket object the maximum amount of time to wait when

attempting to complete the service. While waiting for the service to complete, the MSG instruction is enabled.

If the requested service does not complete before the timeout period expires, the socket object returns a response to the service request.

See the service descriptions in Chapter 2

for the content of the response.

MSG Instruction Timeouts

The default MSG instruction timeout is 30 seconds. The maximum MSG timeout is approximately 35 minutes. Specify the MSG instruction

timeout by setting the appropriate member of the MSG tag:

• If the MSG is unconnected, set the UnconnectedTimeout member.

• If the MSG is connected, set the ConnectionRate and TimeoutMultiplier member.

The MSG timeout is determined by multiplying the ConnectionRate by the TimeoutMultiplier. A TimeoutMultiplier of 0 corresponds to

multiplier of 4, 1 corresponds to multiplier of 8, and so on.

Socket Instance Timeouts

Each socket instance has an inactivity timeout with a default of 5 minutes. If a socket instance receives no service requests for the amount

of time that is specified by the inactivity timeout, the socket instance is deleted. If you then try to use the socket instance, the MSG

instruction receives the error class or instance not supported.

You can change the timeout by setting the inactivity timeout attribute via the Set Attribute service. See Socket Instance Attributes on

page 47.

If you put the controller in Program mode and then back into Run mode before existing socket instances time out, you can receive errors

when the program tries to create socket instances. Eventually the socket instances time out and you can create more instances.

Disable the Socket Object with an MSG Instruction

The socket object is enabled by default. You can use a CIP Generic MSG instruction to disable the socket object.

After you disable the socket object:

• All object-specific services and all instance attributes are unavailable for writing and reading. The Object Enable attribute is read-

only.

• The TCP/IP socket object is disabled, and a factory reset can enable it again.

IMPORTANT Make the value of the service timeout parameter is shorter than the MSG instruction timeout. Otherwise, application

data could be lost.

IMPORTANT Make sure that the inactivity timeout is longer than the longest interval between socket operations. If the inactivity

timeout is too short, socket instances can time out and result in MSG instruction errors.

IMPORTANT The MSG instruction must be sent to the EtherNet/IP module via backplane.

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On the Configuration tab, configure the parameters as described in Table 2.

On the Communication tab, configure the parameters that are described in Table 3

Table 5 - Configuration Tab

Field Description

Message Type Choose CIP Generic.

Service Type Choose Set Attributes Single.

Service Code 10 (hex)

Class 342 (hex)

Instance 0

Attribute 9 (hex)

Source Element Choose the SINT tag that contains the value of zero.

Source Length 1

Destination Element Not required.

IMPORTANT If you are using the front Ethernet port on a controller, you must use unconnected MSG instructions.

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Chapter 1 Socket Interface Architecture

Programming Considerations

Observe these programming considerations.

TCP Connection Loss

Your application program can encounter conditions that result in TCP connection loss. For example, a network cable can be unplugged, or a

target device can be turned off.

Your application program detects the loss of TCP connections and handles those events appropriately. You can detect connection loss when

one of the following occurs:

• The ReadSocket service returns with an error.

• The WriteSocket service returns an extended error code other than 16#0000_0046. See Error Codes for Socket Services on page 51

Depending on the application, try these actions:

• Try to re-establish the connection if there is a client connection.

• Wait for another incoming connection to be established if there is a server connection.

If you want to re-establish communication with the other device, complete these actions:

• Delete the socket instance for the lost connection.

• If the connection is a client connection, create a socket instance and issue an OpenConnection service to the target device.

• If the connection is a server connection, issue an AcceptConnection service to wait for another connection from the remote device.

Table 6 - Communication Tab

Field Description

Path

Enter the communication path to the EtherNet/IP module. The module must be accessed via the backplane; you cannot access the module via the

Ethernet port.

• For all controllers and communication modules, the path is 1, x. Where x is the slot number of the communication module, or the slot number of a

ControlLogix 5580 controller if the front Ethernet port is used.

• For all supported CompactLogix controllers, the slot is 0.

• For all CompactLogix 5370, CompactLogix 5380, Compact GuardLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix 5580

controllers with version 28.11 or later, you can also use a path of ‘THIS’.

IMPORTANT User code must manage messages so that only one message to a socket instance is active at a time. For example, the

read and write socket instructions for a given socket should be interlocked so that only one executes at a time. This is

on a per socket basis.

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Chapter 1 Socket Interface Architecture

ControlLogix Redundancy

If your application uses sockets in an enhanced redundancy system, your application program must manage switchovers in these ways:

• After a switchover, socket instances in the EtherNet/IP module in the old primary chassis must be recreated in the EtherNet/IP

module in the new primary chassis via controller logic.

• Sockets that are connected outside of the enhanced redundancy system must recognize that communication is lost with socket

instances in the EtherNet/IP module in the old primary chassis after a switchover. A change in IP address of the EtherNet/IP module

after a switchover causes loss of communication. See TCP Connection Loss on page 19

• Although socket instances in the EtherNet/IP module in the old primary chassis are automatically deleted once their inactivity timeout

expires, it is possible that a second switchover can occur before the timeout expires. To be sure that these non-functioning socket

instances are deleted before a second switchover, your application program can issue a message to delete all sockets if there is a

switchover before creating functioning socket instances.

To learn more about redundancy systems, refer to the ControlLogix 5570 Redundancy User Manual, publication 1756-UM535

EtherNet/IP Module Reset

If the EtherNet/IP module is reset, for example by cycling power or with removal and insertion under power (RIUP), all socket instances are

lost.

If you create socket instances while MSG instructions are still using the old instance numbers, the new instance numbers can match the old

instance numbers. In this situation, your old MSG instructions can succeed but could not be communicating with the correct remote device.

Handle this situation by monitoring the status of the EtherNet/IP module via a GSV instruction. If you lose communication with the EtherNet/

IP module, the Logix 5000 program reinitializes its socket communication.

Change Controller Mode between Run and Program

If the Logix 5000 controller transitions from Run mode to Program mode while socket requests are active, the transition does not complete

until all outstanding MSG requests complete or time out. If you have long timeout values, you can experience an unexpectedly long time for

the Run-to-Program transition to complete.

Alleviate long transition times by appropriately setting the timeout parameter for the socket services. In the Logix 5000 program, you can

also set the .TO bit for any outstanding socket-related MSG instruction. This causes the MSG instruction to time out and set the .ER bit.

If the controller transitions from Run mode to Program mode, then back to Run mode again, previous socket instances can still exist on the

EtherNet/IP module. The previous socket instances time out eventually. Depending on the number of sockets you need, your program can

encounter errors during Run-Program-Run transitions because all available socket instances are in use.

To alleviate this situation, follow this procedure:

1. Wait for all socket instances to time out before putting the controller in Run mode.

2. When the Logix 5000 program starts, use the DeleteAllSockets service to delete any previous instances.

The DeleteAllSockets service deletes all socket instances, not just those instances that the controller that calls the service creates.

Application Messages and TCP

A TCP connection is a byte stream between two application entities. The application protocol determines the message formats. Messages

can be fixed size or variable size.

If an application sends variable size messages, a common strategy is to first send a fixed-size header that contains the size of the message

followed by the message. The receiving device can first issue a ReadSocket service of the fixed size header to determine the remaining size,

and then issue a subsequent ReadSocket service to receive the remaining data.

IMPORTANT Socket instances that are created in EtherNet/IP modules are not crossloaded in a redundancy system.

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Chapter 1 Socket Interface Architecture

Application Messages and Inhibited Modules

Unlike I/O connected via an EtherNet/IP module, communication via messaging to socket instances can continue when a module is inhibited.

If you want to stop socket communication when a module is inhibited, your application code must detect the status of the module and take

the appropriate action.

Partial Reads

It is possible for a read service to return a BufLen that is less than the requested amount of data. For example, your program can request 100

bytes of data. Because TCP is a byte stream and not a datagram protocol, you can receive less than 100 bytes when the read service returns.

Depending on the application protocol, issue additional read requests to receive all data. If the application protocol dictates that all

messages are 100 bytes, then you must issue additional read requests until you receive 100 bytes. If the application protocol uses variable

size messages, your program needs additional logic to handle variable message sizes as defined by the application protocol.

When issuing multiple read requests, be careful to adjust the destination tag that receives the data so that data is not overwritten.

If the read request times out before any data is received, a BufLen of 0 is returned with success (0) status.

This fragment of Structured Text logic shows an example of handling a partial read request.

Partial Writes

Although uncommon, sometimes a write service is unable to send all specified bytes if the write service is called multiple times before the

target application can receive the data.

If the write service is not able to send the requested data, your program issues subsequent writes to send the remaining data. Your program

also adjusts the source tag, so that old data is not sent.

If the number of bytes written is less than requested, an extended error is returned, and the actual length of the data sent.

This fragment of Structured Text logic shows an example of handling a partial write service.

/* copy the message we just read */

COP (ReadResponse.Buf[0], ReadBuf[CurrentLen],

ReadResponse.BufLen);

CurrentLen := CurrentLen + ReadResponse.BufLen;

/* do we need to read more data get a complete message? */

if (CurrentLen < ApplicationMsgLen) then

/* issue another read */

ReadParams.BufLen := ApplicationMsgLen - CurrentLen;

MSG (ReadMSG0);

end_if;

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Chapter 1 Socket Interface Architecture

Performance Considerations

The socket interface enables a Logix 5000 controller to communicate via an EtherNet/IP module with Ethernet devices that do not support

the EtherNet/IP application protocol, such as barcode scanners, RFID readers, or other standard Ethernet devices. The socket interface, via

messaging, is not well suited for real-time control as communication with this method is not scheduled or deterministic.

There are various factors that can affect the performance of the socket interface. For examples of some of the factors to consider, see the

Knowledgebase Article 1756-EWEB Performance

if (WriteMSG0.ER) then

/* write failed. if the extended error code was 16#0000_0046,

then it means less than the requested byte were sent. */

if (WriteMSG0.EXERR = 70) then

/* need to issue another write, with the data that was not

sent */

SentLen := WriteResponse; /* here's what was sent */

/* adjust the size */

WriteParams.BufLen := WriteParams.BufLen - SentLen;

/* copy remaining data to send to MSG buffer */

COP (WriteBuf[SentLen], WriteParams.Buf[0],

WriteParams.BufLen);

/* BufLen = Timeout + Sockaddr + data length */

WriteMSG0.REQ_LEN := 4 + 12 + WriteParams.BufLen;

MSG (WriteMSG0);

end_if;

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Chapter 2

Socket Object Services

For a socket object, application data has no inherent byte order. The service receives data in the same byte order as it is sent. However,

Logix 5000® controllers store data in CIP™ byte order (little-endian). For example, if you issue a write service with one DINT, that DINT is sent

over a TCP connection or in a UDP datagram in CIP byte order. If you issue a read service and your destination tag for the response contains

a DINT, the Logix 5000 controller assumes that the incoming data is in CIP byte order. Depending on the byte order of the application that you

are communicating with, you may need to convert the byte order in your Logix 5000 program or in the application.

To check your MSG configuration in the Studio 5000 Logix Designer® application, choose a service type from the Service Type pull-down

menu on the Configuration tab of the Message Configuration dialog box. The software completes the Service Code and Class fields.

With RSLogix 5000® software, version 15 and earlier, choose Custom from the Service Type pull-down menu and manually complete the

Service Code and Class fields.

Socket Create

The Socket Create service creates an instance of the socket object. The service returns an instance number that you use in the subsequent

socket operations. Call the Socket Create service with instance 0 (Socket object class).

MSG Source Element

Choose a tag with a user-defined data type. Use the information in Table 7 to define the data type.

Parameter Value

Service Type Socket Create

Service Code 4b

Class 342

Instance 0

Attribute 0

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Chapter 2 Socket Object Services

MSG Source Length

Specify the size of the user-defined structure for the source element. In this example, CreateParams is 12 bytes.

MSG Destination Element

The MSG instruction returns the instance number of the socket that it created to the destination element. Specify a DINT tag.

Considerations

Use the instance that the Socket Create service returns on subsequent service requests.

Use a MOV instruction to move the instance to another MSG tag (the .Instance field).

If you use a local port number that is already in use by the EtherNet/IP™ module, you receive extended error code 16#0000_0030. Avoid using

commonly used ports.

When a CompactLogix 5380, Compact GuardLogix 5380, and CompactLogix 5480 controller operate in Dual-IP mode, the default IP address

for use with a Socket_Create service type is 0.0.0.0.

• If you use 0.0.0.0, IP communication that the Socket Object instance initiates follows the same routing rules as DNS request routing

rules described in these publications:

- CompactLogix 5380 and Compact GuardLogix 5380 Controllers User Manual, publication 5069-UM001

- CompactLogix 5480 Controllers User Manual, publication 5069-UM002

• If you use the IP address of port A1 instead of 0.0.0.0, IP packets can only go to the port A1 subnet or via its default gateway.

• If you use the IP address of port A2 instead of 0.0.0.0, IP packets can go only to port A2 subnet or via its default gateway.

• If you use the IP address of port B1 instead of 0.0.0.0, IP packets can only go to the port B1subnet or via its default gateway.

• If you use an IP address other than the port A1 or A2 IP addresses or 0.0.0.0, the Create_Socket_Service request is rejected.

Table 7 - Data Type for Socket Create Source Element

Member Name Data Type Description

Type DINT

Specify one of these values:

• 1 for TCP

• 2 for UDP

Addr structure A user-defined structure that specifies the address for the socket.

Family INT Specify the address family. Must be 2.

Port INT

Specify the local port number on which an application listens and receives. If you want a port that is randomly assigned,

use port 0.

Addr DINT

Specify an IP address. Typically, set to 0 (any address) for a CompactLogix™ 5370, CompactLogix 5380, Compact

GuardLogix® 5380, CompactLogix 5480, ControlLogix® 5580, GuardLogix 5580 controller in Linear/DLR mode.

For CompactLogix 5380, Compact GuardLogix 5380, and CompactLogix 5480 controllers in Dual-IP mode, the IP address

must be set in HEX format with 1 byte per octet. See Knowledgebase Article 5380 Ethernet Socket Errors and Path

Information.

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Chapter 2 Socket Object Services

OpenConnection

The OpenConnection service does one of the following:

• Opens a TCP connection with the specified destination address

• For UDP, associates a destination IP address and port number with the specified socket

MSG Source Element

Choose a tag with a user-defined data type. Use the information in Table 8 to define the data type.

The MSG instruction that issues the OpenConnection service has a source length of 8 (Timeout + AddrLen) plus the number of characters in

the destination address.

MSG Source Length

Specify 8 bytes (Timeout + AddrLen) + number of characters in the destination address.

MSG Destination Element

Not used. The MSG instruction does not return any data.

Table 8 - Data Type for OpenConnection Source Element

Member Name Data Type Description

Timeout DINT Specify the timeout in milliseconds.

DestAddr STRING

Specify an array of characters (maximum of 64) to define the destination of the connection. You can specify either

Hostname or IP address.

• Hostname?port=xxxzaz

• IPAddr?port=xxx

For example, to specify an IP address, enter 10.88.81.10?port=2813

.LEN DINT The length of the destination address.

.DATA SINT array The array that contains the destination address.

Parameter Value

Service Type OpenConnection

Service Code 4c

Class 342

Instance from Socket Create

Attribute 0

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Chapter 2 Socket Object Services

Considerations

In some cases, the OpenConnection service can return before the timeout period without creating a TCP connection. For example, if the

destination device is running, but is not listening for connections on the specified port number, the OpenConnection service returns with an

error before the timeout period.

For UDP, the information you must specify depends on whether you use the OpenConnection service:

• If you use the OpenConnection service, you do not have to specify the IP address and port number each time you send data. If you do

not specify an IP address and port number, you can receive data only from the previously specified IP address and port number until

you call the OpenConnection service to specify another IP address and port number.

• If you do not use the OpenConnection service, you must specify the destination address each time you call the WriteSocket service to

send data. When you call the ReadSocket service, you receive the data and the address of the sender. You can then use the address of

the sender to send a response via the WriteSocket service.

If you call the OpenConnection service on a UDP socket with an AddrLen of 0, this removes the association with the destination address.

AcceptConnection

The AcceptConnection service accepts a TCP connection request from a remote destination. Before calling the AcceptConnection service,

call the Socket Create service and specify the local port number that accepts the connection. When the AcceptConnection service

completes, it returns a socket instance that you use to send and receive data on the newly created connection.

The AcceptConnection service is not valid for UDP sockets.

MSG Source Element

Choose a DINT tag to contain the timeout in milliseconds.

MSG Source Length

Specify 4 bytes (Timeout).

Parameter Value

Service Type AcceptConnection

Service Code 50

Class 342

Instance from Socket Create

Attribute 0

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Chapter 2 Socket Object Services

MSG Destination Element

Choose a tag with a user-defined data type. Use the information in Table 9 to define the data type.

Considerations

Create a separate socket instance with the Socket Create service for each port number that accepts connections. After you create socket

instances, call the AcceptConnection service to wait for an incoming connection request. You can accept connections on the same port

number. Each call to the AcceptConnection service returns another instance number to use to read and write data.

ReadSocket

The ReadSocket service reads data on a socket. You specify the number of bytes to receive. The service returns the number of bytes

received.

For TCP, the ReadSocket service returns when any data is received, up to the requested number of bytes. If no data is received before the

timeout period, the service returns a status of success by setting a message instruction Done Bit (.DN) and a BufLen of 0. The service can

return fewer bytes than were requested. Your application can require multiple read requests to receive an entire application message.

For UDP, the ReadSocket service completes when a datagram is available.

Table 9 - Data Type for AcceptConnection Destination Element

Member Name Data Type Description

Instance DINT

Contains the instance for this service. Use this Instance on subsequent Read and Write services for this

connection.

IMPORTANT: Copy this Instance number to Read and Write Messages

Addr structure A user-defined structure that contains the address for the socket.

Family INT Contains the address family. Must be 2.

Port INT Contains a remote port number.

Addr DINT Contains a remote IP address.

Parameter Value

Service Type ReadSocket

Service Code 4d

Class 342

Instance See Instance

Attribute 0

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Chapter 2 Socket Object Services

Instance

This service uses the instance that is returned from the CreateConnection service. However, when accepting a connection via the

AcceptConnection service, use the instance that is returned from this AcceptConnection service as the ReadSocket instance.

MSG Source Element

Choose a tag with a user-defined data type. Use the information in Table 10 to define the data type.

MSG Source Length

Specify 8 bytes (Timeout + BufLen).

MSG Destination Element

Choose a tag with a user-defined data type. Use the information in Table 11 to define the data type.

Table 10 - Data Type for ReadSocket Source Element

Member Name Data Type Description

Timeout DINT Specify the timeout in milliseconds.

BufLen DINT Specify the number of bytes of data to receive.

Table 11 - Data Type for ReadSocket Destination Element

Member Name Data Type Description

FromAddr structure

A user-defined structure that can contain the address of the device that sends UDP data. This structure is populated

from the end device.

For TCP or UDP with OpenConnection, this structure is not used and contains all zeros. The TCP connection conveys all

remote address information.

Family INT Contains the address family for UDP. Must be 2.

Port INT

Contains the remote port number for UDP. The remote device uses this port for sending.

0 is an invalid port number for UDP.

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Chapter 2 Socket Object Services

WriteSocket

The WriteSocket service sends data on a socket. You specify the number of bytes to send. The service attempts to send the requested

number of bytes and returns the number of bytes sent.

Instance

This service uses the instance that is returned from the CreateConnection service. However, when accepting a connection via the

AcceptConnection service, use the instance that is returned from this AcceptConnection service as the WriteSocket instance.

MSG Source Element

Choose a tag with a user-defined data type. Use the information in Table 12 on page 30 to define the data type.

Addr DINT Contains the remote IP address for UDP

BufLen DINT Contains the number of bytes of data received.

Buf SINT array

Contains the data.

This number must be large enough to contain the maximum amount of data expected. For a standard connection, the

maximum is SINT[484]. For a large connection, the maximum is SINT [3984].

Table 11 - Data Type for ReadSocket Destination Element

Member Name Data Type Description

Parameter Value

Service Type WriteSocket

Service Code 4e

Class 342

Instance See Instance

Attribute 0

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Chapter 2 Socket Object Services

MSG Source Length

Specify 16 bytes (Timeout + Addr + BufLen) + number of bytes to write.

MSG Destination Element

The MSG instruction returns the number of bytes that were written. Choose a DINT tag.

DeleteSocket

The DeleteSocket service deletes a socket instance. For a TCP connection, the DeleteSocket service also closes the connection before it

deletes the instance.

MSG Source Element

Not used.

MSG Source Length

Specify 0 bytes.

MSG Destination Element

Not used.

Table 12 - Data Type for WriteSocket Source Element

Member Name Data Type Description

Timeout DINT Specify the timeout in milliseconds.

ToAddr structure

A user-defined structure that contains the address to which to write UDP data.

For TCP or UDP with OpenConnection, this structure is not used and contains all zeros. The TCP connection conveys all

required remote address information.

Family INT Specify the address family. Must be 2 for UDP.

Port INT

Specify the remote port number for UDP. This is the port that the remote device uses for receiving.

0 is an invalid port number for UDP.

Addr DINT

Specify the remote IP address for UDP.

0.0.0.0 is an invalid IP address for UDP.

BufLen DINT Specify the number of bytes of data to write.

Buf SINT array

Contains the data.

This number must be large enough to contain the maximum amount of data expected. For a standard connection, the

maximum is SINT[472]. For a large connection, the maximum is SINT [3972].

Parameter Value

Service Type DeleteSocket

Service Code 4f

Class 342

Instance from Socket Create

Attribute 0

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Chapter 2 Socket Object Services

Considerations

Delete a socket instance if it is no longer needed. If unused instances are not deleted and you continue to create additional instances, you

can exceed the maximum number of instances.

DeleteAllSockets

The DeleteAllSockets service deletes all currently created socket instances. For TCP, the DeleteAllSockets service also closes all connections

before it deletes the instances.

Choose Custom for the service type. DeleteAllSockets is not an available option from the Service Type pull-down menu.

MSG Source Element

Not used.

MSG Source Length

Specify 0 bytes.

MSG Destination Element

Not used.

Considerations

Call the DeleteAllSockets service with instance 0.

Use the DeleteAllSockets service as the first operation when the program first begins to operate.

IMPORTANT Be careful with the DeleteAllSockets service when there are multiple controllers that use the socket interface of the

EtherNet/IP module. The service deletes all socket instances that are created by all controllers, not just the controller

that calls the service.

Parameter Value

Service Type Custom

Service Code 51

Class 342

Instance 0

Attribute 0

32 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 2 Socket Object Services

ClearLog

The ClearLog service clears the debug log on the TCP/IP Socket Object webpage. This service does not change the logging options.

Choose Custom for the service type. ClearLog is not an available option from the Service Type pull-down menu.

MSG Source Element

Not used.

MSG Source Length

Specify 0 bytes.

MSG Destination Element

Not used.

JoinMulticastAddress

Joining a multicast group lets a socket receive multicast data. When a join is executed, it sends an IGMP membership packet and enables the

hardware filters to receive the multicast data. A specific address can be joined only once. Subsequent joins receive an error message until

the multicast address is dropped. Multicast joins are system wide. Two sockets cannot join the same multicast address simultaneously.

When the socket that the join was executed on is deleted, the multicast address is dropped. Each socket can join one or more multicast

groups.

Choose Custom for the service type. JoinMulticastAddress is not an available option from the Service Type pull-down menu.

IMPORTANT The TCP/IP Socket Object webpage is not visible on ControlLogix 5580, GuardLogix 5580, CompactLogix 5380,

Compact GuardLogix 5380, and CompactLogix 5480 controllers.

Parameter Value

Service Type Custom

Service Code 52

Class 342

Instance 0

Attribute 0

Parameter Value

Service Type Custom

Service Code 53

Class 342

Instance from Socket Create

Attribute 0

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 33

Chapter 2 Socket Object Services

MSG Source Element

Choose a tag with a user-defined data type. Use the information in Table 13 to define the data type.

Populate the Join_Source_Data.Addr field with a multicast IP address in hexadecimal format. The value must be a hexadecimal

representation of the IP address. For example, for address 239.1.2.100, enter 16#EF010264.

MSG Source Length

Specify 8 bytes.

MSG Destination Element

Not used.

DropMulticastAddress

Dropping a multicast address disables a socket from receiving multicast data. When a drop is executed, it sends an IGMP leave group packet

and disables the hardware filters from receiving the multicast data.

Choose Custom for the service type. DropMulticastAddress is not an available option from the Service Type pull-down menu.

Table 13 - Data Type for JoinMulticastAddress Source Element

Member Name Data Type Description

SocketsAddr structure A user-defined structure that specifies the multicast address to join.

Family INT Specify the address family. Must be 2.

Port INT Not used. The port is determined when the socket is created.

Addr DINT Specify the multicast IP address to receive from.

Parameter Value

Service Type Custom

Service Code 54

Class 342

Instance from Socket Create

Attribute 0

34 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 2 Socket Object Services

MSG Source Element

Choose a tag with a user-defined data type. Use the information in Table 14 on page 34 to define the data type.

MSG Source Length

Specify 8 bytes.

MSG Destination Element

Not used.

Table 14 - Data Type for DropMulticast Address Source Element

Member Name Data Type Description

SocketsAddr structure A user-defined structure that specifies the multicast address to drop.

Family INT Specify the address family. Must be 2.

Port INT Not used. The port is determined when the socket is created.

Addr DINT Specify the multicast IP address to drop.

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 35

Chapter 3

Socket Attributes

You access socket attributes by configuring a CIP™ Generic MSG instruction to get or set the specific attribute:

• To change an attribute value for a socket, choose Set Attribute Single from the Service Type pull-down menu.

• To get a socket value, choose Get Attribute Single from the Service Type pull-down menu.

Some socket attributes apply to all sockets, and some apply to specific socket instances:

• For information about all sockets, type 0 in the Instance field. See Socket Class Attributes

• For information about a specific socket instance, type the specific socket instance number in the Instance field. A Socket Create or

AcceptConnection service returns the instance number. See Socket Instance Attributes on page 36

Socket Class Attributes

Class attributes apply to the socket object, not to specific socket instances. When you get or set a Class attribute, set the instance to 0.

Table 15 - Socket Class Attributes

Class Attribute Name Data Type Access Description

1 Revision INT Get Object revision.

2 Max Instance INT Get Largest socket instance number currently created.

3 Number of Instances INT Get Number of socket instances currently created.

Log Enable

(1)

(1) The Socket Object webpage is not visible on ControlLogix® 5580, GuardLogix® 5580, CompactLogix™ 5380, Compact GuardLogix 5380, and CompactLogix 5480 controllers.

DINT

Get

Set

Enable (1) or disable (0) logging to the Socket Object Log webpage.

Each socket service has a corresponding bit:

• If enabled, requests for that service request are logged.

• If disabled, then requests for that service are not logged.

Bit 0: Socket Create requests

Bit 1: OpenConnection requests

Bit 2: AcceptConnection requests

Bit 3: Read requests

Bit 4: Write requests

Bit 5: DeleteSocket and DeleteAllSockets requests

Bit 6: Get / Set Attribute requests

Bit 7: Log all service errors

9 Object Enable SINT

Get

Set

Enable (1) or disable (0) the Socket Object. Default is enabled.

36 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 3 Socket Attributes

If you use the Get Attributes All service to get class attributes, the response contains all class attributes in Table 15 in the order shown with a

total size of 10 bytes.

If you use the Set Attributes All service to set class attributes, the request contains only the Log Enable class attribute.

Socket Instance Attributes

The socket object provides a number of instance attributes that apply to specific socket instances. To get or set an instance attribute,

specify a valid instance number.

If you use the Get Attributes All service to get instance attributes, the response contains all attributes in Table 16

in the order that is shown

with a total size of 36 bytes.

If you use the Set Attributes All service, the request must include attributes 3, 4, 5, 6 and 7 in that order with a total size of 20 bytes.

Table 16 - Socket Instance Attributes

Instance

Attribute

Name Data Type Access Description

1 (16#01) LocalAddr Struct SockAddr Get Local address for the socket.

2 (16#02) RemoteAddr Struct SockAddr Get Remote address for the socket.

3 (16#03) SendBufSize DINT

Get

Set

Size of the socket send buffer (bytes).

4 (16#04) RecvBufSize DINT

Get

Set

Size of the socket receive buffer (bytes).

5 (16#05) TCPKeepAlive DINT

Get

Set

Enable (1) or disable (0) TCP Keep Alive for the socket.

Enabled by default.

6 (16#06) TCPNoDelay DINT

Get

Set

Enable (1) or disable (0) the TCP No Delay behavior.

Enabled by default.

7 (16#07) InactivityTimeout DINT

Get

Set

Time for the inactivity timeout (default of 5 minutes). If a socket instance

receives no service requests for the amount of time that is specified by the

inactivity timeout, the socket instance is deleted. If you then try to use the

socket instance, the MSG instruction receives the error Class or instance not

supported.

8 (16#08) MulticastTTL DINT

Get

Set

Set the TTL value for UDP multicast, transmitted packets.

9 (16#09) UDPBroadcast DINT

Get

Set

Enable (1) or disable (0) the ability to transmit broadcast packets on UDP.

Disabled by default.

10 (16#0A) LingerOnOff DINT

Get

Set

Specifies whether the socket performs an orderly close (1) or an immediate

close (0).

Defaults to no linger (immediate close). For TCP sockets, setting linger to 0

results in a TCP RST packet to close the connection. If you set linger to

nonzero, then it results in the standard TCP connection close sequence (3-way

FIN, FIN-ACK, ACK handshake followed by TIME_WAIT).

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 37

Chapter 4

Troubleshoot Socket Applications

To help you troubleshoot socket applications, this chapter describes the following resources:

• Diagnostic webpages

• Debugging tips

• Error codes

• Knowledgebase articles

Diagnostic Webpages

To help debug and troubleshoot applications, the socket interface provides a set of webpages:

• For communication modules and controllers, go to Diagnostics > Advanced Diagnostics > Miscellaneous > System Data > Socket

Object.

• For web server modules, go to Diagnostics > Advanced Diagnostics.

IMPORTANT The Socket Object webpage is not visible on ControlLogix® 5580, GuardLogix® 5580, CompactLogix™ 5380, Compact

GuardLogix 5380, and CompactLogix 5480 controllers.

Webpage Description

Socket Object Diagnostics

Displays information about each instance:

• Instance number

• Socket type—client, server, or listen

• Local and remote ports and IP addresses

• Send and receive buffer sizes

• Socket up time and inactivity time

• Socket state and last error state

Socket Object Attributes Displays attribute settings for each instance

Socket Object Logs

Displays a log of service requests with a maximum of 100 log entries:

• Service requests made to the socket object

• Parameters that are passed for each service request

• Whether the service request was a success or failure

You can enable or disable logging for some services by using the Log Enable class attribute. See Socket Class Attributes on

page 35.

38 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 4 Troubleshoot Socket Applications

Debugging Tips

This table describes tips for debugging problems by category.

Error Codes for Socket Services

If a socket object encounters an error with a service request, the following occurs:

• Socket object returns an error code.

• MSG instruction sets the .ER bit.

• MSG instruction sets error codes in the Error (.ERR) and Extended Error (.EXTERR) fields.

This table describes common error codes. For more a comprehensive list of error codes, see the Knowledgebase article Logic Sockets

Services Error Codes.

Category Consideration

EtherNet/IP™ module

Make sure the EtherNet/IP module has a valid IP address. Also, if you communicate with devices on different subnets,

configure the EtherNet/IP module with a valid subnet mask and gateway address.

Socket Create service

Make sure that the Destination tag is a DINT tag.

After creating the socket with the Socket Create service, make sure that you use the instance number that the service returns

in the subsequent socket services you call.

MSG instruction

Make sure that the Source Element is of a type that matches the request parameters for the requested service. Also make sure

that the Source Length is the correct length for the service parameters.

There is a limit to the number of active MSG instructions in a Logix 5000® controller. If an MSG instruction is enabled and

exceeds the maximum number of active MSG instructions, the MSG instruction receives an error (.ER bit set).

OpenConnection service

Make sure that the Source Length includes the size of the Timeout parameter + Address Length parameter + the Length of the

address itself.

Service Timeout parameter

Make sure that the Timeout parameter is sufficient for the service. Also make sure that the Timeout parameter is less than the

MSG instruction timeout.

If the timeout is set to 0, the service returns immediately.

TCP protocol

A TCP connection is a byte stream with no inherent message boundaries. The application defines how to interpret message

boundaries. For example, the application can use a fixed length for all messages. For a variable-length message, the

application can use a fixed-length header that contains the length of the remainder of the message.

Both ends of the TCP connection must agree on the application protocol that is used.

"our program should handle the loss of TCP connections in case they get dropped due to network issues or other reasons.

Ethernet sniffer

An Ethernet sniffer is useful to monitor the messages between the EtherNet/IP module and other devices. You can capture

network traffic and create filters to isolate messages between particular devices and particular messages between those

devices.

Table 17 - Common Error Codes

Error Code Extended Error Code Description

16#0001 16#0000_0117

An invalid path was programmatically entered in the MSG.Path string via COP or another string manipulation command.

For more information, see the Knowledgebase article, Sockets Error code 16#0001 Extended Code 16#0000_0117

16#0001

16#0000_0318

16#0000_0103

When configuring a CIP Generic MSG instruction for Open Socket communication, all CompactLogix 5370 controllers must use

unconnected MSG instructions.

If you configure an MSG instruction for a CompactLogix 5370 controller, make sure that the Connected checkbox is cleared on

the Communication tab of the Message Configuration dialog box (page 16

16#0001

16#0000_0900

through

16#0000_0915

See the I/O fault code descriptions in Logix 5000 Controller and I/O Fault Codes, publication 1756-RD001

16#0002 Simultaneous execution of Read, Write, or Delete messages.

16#0004

An attempt to access the socket object via the Ethernet port is blocked because of resiliency concerns.

For more information, see the Knowledgebase article, Logix Sockets message error 16#0004

16#0005

16#0000_0000

16#0000_0001

1. Ethernet module does not have firmware that supports Logix Sockets.

2. The socket instance does not exist. This error can occur in these scenarios:

– The socket instance number that the Socket Create service returned does not match the instance number in the socket

read or write message.

– The socket instance closed due to inactivity.

– The DeleteSocket service deleted the socket.

16#0006

Failed attempt to write more than 460 bytes with a CompactLogix 5370 controller. SocketWrite messages are limited to

460 bytes with CompactLogix 5370 controllers. This value is specified in the MessageSourceBuffLen tag.

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 39

Chapter 4 Troubleshoot Socket Applications

16#0008

A 1756-ENxT or 1756-ENxTR module that is used for socket messages is in a remote chassis that is connected to the controller

over the ControlNet® network or is using an older EtherNet/IP module that supports only 478-byte messages.

For more information, see the Knowledgebase Article Open Sockets: Message Read/Write error 16#0008 if "Large Connection"

option is enabled.

16#0009

Invalid socket descriptor. To resolve this error, do the following:

• Make sure that a valid socket instance exists.

• Make sure that the message source data format and source values are correct.

• For Create messages, make sure that Type and Family is set correctly.

• For UDP Read/Write messages, make sure that Source tag member Family is set to 2.

16#000b

16#000c

The Open (Connect) message instruction and Accept message were executed on the same socket.

For more information, see the Knowledgebase Article Open Sockets Error codes 16#000b, 16#000c

16#000d Invalid data in Source UDT.

16#0011

Failed attempt to read more than 484 bytes with a CompactLogix 5370 controller. SocketRead messages are limited to

484 bytes with CompactLogix 5370 controllers. This value is specified in the MessageSourceBuffLen tag.

16#0013

16#0015

The ‘Write’ message instruction Source length must be exactly equal to the buffer length+16.

For more information, see the Knowledgebase Article Open Sockets Error code 16#0013 and 16#0015

16#0020

The ‘Write’ message instruction Source length is less than 17 bytes. Length must be exactly equal to the buffer length+16.

For Connect messages, make sure that the Destination String address includes ‘?port=xxxx’ similar to 192.168.1.34?port=9100.

For more information, see the Knowledgebase Article 1756-EN2T, 1756-EWEB sockets error 16#0020

16#00ff

16#0000_0016

16#0000_0033

Open Sockets (TCP Client) is unable to connect to a third-party device (Slave). The device reports WIN=0 and the 1756-EN2T

module immediately closes the connection. For more information, see the Knowledgebase Article Open Sockets: Open

connection fails with error 16#0000_0046,16#0000_0016 or 16#0000_0033.

16#00ff 16#0000_0030 The address is already in use. This error can occur when multiple Socket Create requests are issued to the same port address.

16#00ff 16#0000_0036

A connection was forced closed by a peer. This error can occur when a remote device closes a connection with a Logix

module without notifying the module.

To resolve this error, delete the socket and then reconnect to the remote device.

16#00ff 16#0000_0039 In Server mode, instance number from Accept Message was not copied to Read/Write messages.

16#00ff 16#0000_003d

A connection refused by a peer. Possibly peer is out of connections if Logix module closes them without Linger Attribute set.

For more information, see the Knowledgebase Article Logix Open Sockets Linger Control

16#00ff 16#0000_0041

A socket operation could not find a route to the remote host. This error typically occurs in these scenarios:

• A remote IP address that is specified in the MSG instruction is not on the same subnet as the Logix module.

and

The IP address of the gateway or router is not specified in the Logix module properties.

• UDP multicasts messages to an unpingable IP address require you to specify a gateway address in the Logix module

properties even if a gateway address does not exist or is not required.

For more information, see the Knowledgebase Article 1756-EWEB socket errors 16#0041 and 16#0043

16#00ff 16#0000_0043

The remote device or gateway is not responding.

This error can occur if a UDP multicast message is sent to a gateway address that is not specified in the Logix module

properties.

For more information, see the Knowledgebase Article 1756-EWEB socket errors 16#0041 and 16#0043

16#00ff 16#0000_0046

The socket operation timed out. Known reasons include the following:

• Connect Service message:

– Server IP exists, but port does not.

– Server IP and port exist, but does not accept connections on this port.

– Service timeout value in UDT set to 0 or low value.

The peer device reports WIN=0 and the 1756-EN2T module immediately closes the connection. For more information, see the

Knowledgebase Article Open Sockets: Open connection fails with error 16#0000_0046,16#0000_0016 or 16#0000_0033.

• Read/Write Service message:

– Read and write executed simultaneously.

For more information, see the Knowledgebase Article Open Sockets message Error 16#00FF extended 16#0000_0046

• UDP Read message only:

– UDP Receive buffer is empty with no new incoming data.

16#00ff 16#0009_0315 Invalid path string manually or programmatically entered to the MSG.Path string.

16#00d0 16#0000_0001 CA certificate file has a loading error.

16#00d0 16#0000_0002 Trusted peer certificate file has a loading error.

16#00d0 16#0000_0003 Both certificate files have a loading error.

16#00d0 16#0000_0004 No resources for the TLS session.

16#00d0 16#0000_0005 Unknown error during TLS handshake.

Table 17 - Common Error Codes (Continued)

Error Code Extended Error Code Description

40 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Chapter 4 Troubleshoot Socket Applications

Exposing TLS Errors

During the TLS handshake process, errors can occur that are not covered by the CIP specification but are defined in various RFCs. These

errors are exposed through extended status codes 16#0000_0900…16#0000_0915, as defined in Logix 5000 Controller and I/O Fault Codes,

publication 1756-RD001

Knowledgebase Articles

For additional help, see these Knowledgebase articles:

Knowledgebase Article Description

Sample Application for Ethernet module Sockets Feature

Sample applications for the 1756-EWEB module and CompactLogix 5380 controllers.

Logic Sockets Services Error Codes

Descriptions of possible socket error codes.

EWEB socket services hints

Helpful hints for EWEB socket services.

Summary of Logix Socket Information

Summary of major sockets topics and functionality descriptions.

RSLogix 5000®: AOI example for using sockets to read time from NTP or SNTP

server

Add-On Instruction example for using sockets to read time from NTP or SNTP server

Example Add On Instructions for Sockets

Using sockets in AOIs (Add-on Instructions).

Email with Basic Login Authentication Using Sockets and AOI

Using Sockets for Email with Basic Login Authentication

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 41

Index

AcceptConnection service 26 - 27

access

Knowledgebase

MSG configuration 23

socket attributes

application messages

TCP considerations

uninhibited module considerations

architecture, socket interface

number and type of sockets

overview

TCP client transactions

TCP server transactions

UDP communication

11 - 12

attributes

access via MSG instruction

socket class attributes

socket instance attributes

socket object

broadcast 8

change

controller mode

socket attribute value

class attributes

ClearLog service

client socket, TCP

codes, error

communication

socket object

15 - 16, 17

UDP

11 - 12

connection loss

considerations, programming

19 - 21

controller mode

ControlLogix enhanced redundancy

crossload

datagram 11, 21, 23, 27

debugging

37 - 40

DeleteAllSockets service

DeleteSocket service

diagnostic web pages

DropMulticastAddress service

33 - 34

dropped connection

enhanced redundancy 20

error codes

Ethernet sniffer

EtherNet/IP module

debug

reset

instance attributes 36

instance, socket

instruction, MSG

socket attributes

socket communication

15 - 16, 17

timeouts

interface architecture

JoinMulticastAddress service 32 - 33

Knowledgebase articles 40

listen socket, TCP 8

Logix5000 controller

as TCP client

as TCP server

logs, socket object

maximum packet size 16

messages

TCP considerations

uninhibited module considerations

mode, controller

module reset

MSG configuration 23

MSG instruction

debugging

socket attributes

socket communication 15 - 16

timeouts

multicast

OpenConnection service

about

25 - 26

debugging

packet size 16

partial reads

partial writes

Program mode

42 Rockwell Automation Publication ENET-AT002E-EN-P - January 2023

Index

programming considerations 19 - 21

protocol, TCP

reads, partial 21

ReadSocket service

27 - 29

redundancy, enhanced

request socket services

reset

Ethernet/IP module

Run mode

secure socket object 13

sequence of transactions

TCP client

TCP server

UDP communication

11 - 12

server socket, TCP

Service Timeout parameter

service timeouts

services

AcceptConnection

26 - 27

ClearLog

DeleteAllSockets

DeleteSocket

DropMulticastAddress

33 - 34

JoinMulticastAddress

32 - 33

OpenConnection

25 - 26

ReadSocket

27 - 29

Socket Create

WriteSocket

29 - 30

size, packet

sniffer, Ethernet

socket class attributes

Socket Create service

about

debugging 38

socket instances

attributes

crossload

timeouts 17

types of

socket interface

architecture

MSG instructions

number and type of sockets

programming considerations

19 - 21

service timeouts

TCP client 9

TCP client transactions

TCP server

TCP server transactions

UDP communication

11 - 12

socket object attributes

socket object diagnostics

socket object logs

socket object services

AcceptConnection

26 - 27

ClearLog

DeleteAllSockets

DeleteSocket 30

DropMulticastAddress

33 - 34

error codes

instances

JoinMulticastAddress

32 - 33

OpenConnection

25 - 26

overview

8, 23

ReadSocket

27 - 29

Socket Create

timeouts

WriteSocket

29 - 30

switchover

TCP application messages 20

TCP client socket

TCP client transactions

TCP communication

8, 9 - 10

TCP connection loss

TCP listen socket

TCP protocol

TCP server socket

TCP server transactions

timeout parameter

timeouts

tips for debugging

TLS

transaction sequence

TCP client

TCP server

UDP communication 11 - 12

troubleshooting

debugging tips

diagnostic web pages

error codes

Knowledgebase articles

UDP communication 8, 11 - 12

UDP socket 8

unicast

uninhibited modules

application message considerations

web pages, diagnostic 37

writes, partial

WriteSocket service

29 - 30

Rockwell Automation Publication ENET-AT002E-EN-P - January 2023 43

EtherNet/IP Socket Interface Application Technique

Additional Resources

These documents contain additional information concerning related products from Rockwell Automation. You can view or download

publications at rok.auto/literature

Resource Description

EtherNet/IP Network Devices User Manual, ENET-UM006

Describes how to configure and use EtherNet/IP devices to communicate on the EtherNet/IP

network.

Ethernet Reference Manual, ENET-RM002

Describes basic Ethernet concepts, infrastructure components, and infrastructure features.

System Security Design Guidelines Reference Manual, SECURE-RM001

Provides guidance on how to conduct security assessments, implement Rockwell

Automation products in a secure system, harden the control system, manage user access,

and dispose of equipment.

UL Standards Listing for Industrial Control Products,

publication CMPNTS-SR002

Assists original equipment manufacturers (OEMs) with construction of panels, to help ensure

that they conform to the requirements of Underwriters Laboratories.

American Standards, Configurations, and Ratings: Introduction to

Motor Circuit Design, publication IC-AT001

Provides an overview of American motor circuit design based on methods that are outlined

in the NEC.

Industrial Components Preventive Maintenance, Enclosures, and Contact

Ratings Specifications, publication IC-TD002

Provides a quick reference tool for Allen-Bradley industrial automation controls and

assemblies.

Safety Guidelines for the Application, Installation, and Maintenance of

Solid-state Control, publication SGI-1.1

Designed to harmonize with NEMA Standards Publication No. ICS 1.1-1987 and provides

general guidelines for the application, installation, and maintenance of solid-state control in

the form of individual devices or packaged assemblies incorporating solid-state

components.

Industrial Automation Wiring and Grounding Guidelines, publication 1770-4.1

Provides general guidelines for installing a Rockwell Automation industrial system.

Product Certifications website, rok.auto/certifications

. Provides declarations of conformity, certificates, and other certification details.

Publication ENET-AT002E-EN-P - January 2023

Rockwell Automation Support

Use these resources to access support information.

Documentation Feedback

Your comments help us serve your documentation needs better. If you have any suggestions on how to improve our content, complete the

form at rok.auto/docfeedback.

Technical Support Center

Find help with how-to videos, FAQs, chat, user forums, Knowledgebase, and product

notification updates.

rok.auto/support

Local Technical Support Phone Numbers Locate the telephone number for your country. rok.auto/phonesupport

Technical Documentation Center

Quickly access and download technical specifications, installation instructions, and user

manuals.

rok.auto/techdocs

Literature Library Find installation instructions, manuals, brochures, and technical data publications. rok.auto/literature

Product Compatibility and Download Center

(PCDC)

Download firmware, associated files (such as AOP, EDS, and DTM), and access product

release notes.

rok.auto/pcdc

Rockwell Automation maintains current product environmental compliance information on its website at rok.auto/pec.

Allen-Bradley, CompactLogix, ControlLogix, expanding human possibility, GuardLogix, Logix 5000, MicroLogix, Rockwell Automation, RSLogix 5000, and Studio 5000 Logix Designer, are

trademarks of Rockwell Automation, Inc.

CIP, CIP Security, ControlNet, and EtherNet/IP is a trademark of ODVA, Inc.

Trademarks not belonging to Rockwell Automation are property of their respective companies.

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