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Sample programs for flex i/o analog modules, Plc-3 programming – Rockwell Automation 1794-IF4I, -OF4I, IF2XOF2I, -IF4IXT, -IF4ICFXT, -OF4IXT, IF2XOF2IXT FLEX I/O Isolated Analog Modules User Manual

Page 33

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Publication 1794-6.5.8 - January 2010

Module Programming 33

Sample Programs for FLEX
I/O Analog Modules

The following sample programs show you how to use your analog
module efficiently when operating with a programmable controller.
These programs show you how to:

configure the module

read data from the module

update the module’s output channels (if used)

With RSLogix5000, just read or write the tags provided. RSLogix will
perform the transfer so an explicit block transfer is not required.

These programs illustrate the minimum programming required for
communication to take place.

PLC-3 Programming

Block transfer instructions with the PLC-3 processor use one binary
file in a data table section for module location and other related data.
This is the block transfer control file. The block transfer data file stores
data that you want transferred to your module (when programming a
block transfer write) or from your module (when programming a
block transfer read). The address of the block transfer data files are
stored in the block transfer control file.

The same block transfer control file is used for both the read
and write instructions for your module.
A different block transfer
control file is required for every module.

A sample program segment with block transfer instructions is shown
in Figure 1.1, and described below.