Manual

Publication 1203-5.13 – February, 2002
Chapter
6
Using Messages
Chapter Objectives
Chapter 6 provides information about using messages on the
ControlNet network. It includes the following:
• Required equipment and software.
• Discussion of messaging.
• Examples of rungs that enable messaging.
This chapter assumes you already have experience creating ladder
logic programs and using messages in RSLogix5.
Required Equipment and Software
Before adding messages to a PLC ladder logic program, your PC
should be:
• Running RSLogix5 and RSLinx applications. Refer to
http://www.software.rockwell.com for more information on these
products.
• Connected to and communicating with the ControlNet network
using a 1784-KTCX card, 1784-PCC card or 1770-KFC adapter.
Using Messages
Messaging lets you view and modify SCANport product parameters
as well as provides access to other internal SCANport-related
information and services.
To use messaging, you need to:
1. Insert a MSG rung in your ladder logic program. A unique
message number must be used for each message.
2. Insert a control word in the MSG rung.
3. Configure the message using the MSG dialog box.
The following must be completed in the This PLC-5 section:
•In the Communication Command field, use the drop-down
list to specify whether the MSG instruction performs a read
or write operation and what type of message is used.
•In the Data Table Address field, enter the data table address
containing the message in the controller (e.g., PLC-5).
•In the Size in Elements field, enter the number of elements
being transferred.
•In the Port Number field, enter 2 to enable the ControlNet
dialog parameters.