ProSoft Technology MVI71-DFNT User Manual

Page 70

Reference

MVI71-DFNT ♦ PLC 5

User Manual

EtherNet/IP Client/Server Communication Module

Page 70 of 175

ProSoft Technology, Inc.

February 3, 2011

The MVI71-DFNT module communicates directly over the PLC backplane. Data

is paged between the module and the PLC processor across the backplane using

BTR and BTW operations. Data is transferred from the module to the processor

using the BTR blocks, and data is transferred from the processor to the module

using BTW blocks.

Block Transfer Backplane Data Transfer

The following illustration shows the data transfer method used to move data

between the PLC processor, the MVI71-DFNT module, and the Ethernet

Network.

As shown in the diagram, all data transferred between the module and the

processor over the backplane is through the BTR and BTW blocks. Ladder logic

must be written in the PLC processor to interface the block data with the

module's internal database. All data used by the module is stored in its internal

database. The following illustration shows the layout of the database:

Module’s Internal Database Structure
4000 registers for user data

3999