Explicit messaging – Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 User Manual, Firmware rev. 3.0 or LATER User Manual

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Publication 1404-UM001F-EN-P - November 2009

Chapter 4 Communication

Please contact Rockwell Automation technical support if you find that
the default settings do not result in adequate network performance.

Explicit Messaging

Use explicit messaging to read and write all data tables other than the
I/O messaging table. The specific details of explicit messaging depend
upon the master device that initiates the message. The example in this
section uses an Allen-Bradley SLC 500 controller and DeviceNet
Scanner (1747-SDN) as the master.

Refer to the DeviceNet Scanner Module Installation Instructions,
publication 1747-IN058, for a detailed description of explicit message
programming in the SLC 500 controller.

Please refer to the Rockwell Automation KnowledgeBase for other
examples of explicit messaging to a Powermonitor 3000 unit.

In the SLC 500 and PLC-5 controllers, you assemble the explicit
message header in an integer file and transfer it to the scanner
module. When the response is received, you transfer the response
from the scanner to another integer file. The message header consists
of 6 words organized as follows.

Explicit Messaging

Message

Word

High byte

Low byte

Header

0

Transmit ID

Command

1

Port

Size

2

Service

MAC ID

Body

3

Class

4

Instance

5

Attribute

6

Data to write if applicable

7

. . .

n

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