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Input word offset – Rockwell Automation 1761-NET-DNI DeviceNet Interface (DNI) User Manual

Page 34

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Publication 1761-UM005B-EN-P - October 2006

34 DNI Configuration Parameters and Programming Notes

Input Word Offset

This parameter identifies the starting word within the input file
identified by the parameter Input Data File. The value entered is the
first word of data that is read from the controller attached to the DNI.

The sizes of compatible data files within Allen-Bradley controllers vary
based on the DFI device selected.

Parameter
Type

Parameter Number

Description

Range

Default Value

Series A

Series B

I/O

7

5

Input Word Offset

0…254

0

Compatible Data File Sizes

Controller

Input Data Files

File Size

MicroLogix 1000

Bit

32 Words

Integer

105 Words

SLC/Other MicroLogix

Bit

255 Words

Integer

255 Words

PLC

Bit

999 Words

Integer

999 Words

TIP

The DNI can only access files 3 through 254.

IMPORTANT

You must have sufficient room in the file that you
select. Make sure the Input Word Offset plus the
Input Size does not exceed the boundary of the
controller’s data file. For example, a MicroLogix 1000
controller has 32 words in its bit file; therefore, you
could not use a Input Word Offset of 30 and a Input
Size of 5 because this exceeds the file size.