Mapping tags – Rockwell Automation 1734-AENTR EtherNet/IP Network Configuration User Manual User Manual

Page 84

Advertising
background image

84

Rockwell Automation Publication ENET-UM001L-EN-P - March 2014

Chapter 6 Interlocking and Data Transfer between Controllers

Mapping Tags

A Logix5000 controller stores tag names on the controller so that other devices
can read or write data without having to know physical memory locations. Many
products only understand PLC/SLC data tables, so the Logix5000 controller
offers a PLC/SLC mapping function that enables you to map Logix tag names to
memory locations.

You have to map only the file numbers that are used in messages; the other

file numbers do not need to be mapped.

The mapping table is loaded into the controller and is used whenever a

logical address accesses data.

You can access only controller-scoped tags (global data).

For each file that is referenced in a PLC-5 or SLC command, make a map

entry with one of these methods:
Typing the PLC/SLC file number of the logical address
Typing or selecting the Logix5000 controller-scoped (global) tag that

supplies or receives data for the file number (You can map multiple files
to the same tag.)

For PLC-2 commands, specify the tag that supplies or receives the data.

When mapping tags, remember these guidelines:

Do not use file numbers 0, 1, and 2. These files are reserved for Output,

Input, and Status files in a PLC-5 processor.

Use PLC-5 mapping only for tag arrays of data type INT, DINT, or

REAL. Attempting to map elements of system structures may produce
undesirable effects.

Use the PLC file identifier of N or B when accessing elements in an INT

tag array.

This example shows how to use a buffer of INTs.

Advertising