ProSoft Technology MVI69-DFNT - Manual (Page 82)

Reference MVI69-DFNT ♦ CompactLogix or MicroLogix Platform
User Manual EtherNet/IP Client/Server Communication Module
Page 82 of 167 ProSoft Technology, Inc.
May 14, 2014
Block Transfer Backplane Data Transfer
The MVI69-DFNT module communicates directly over the CompactLogix or
MicroLogix backplane. Data is paged between the module and the CompactLogix
or MicroLogix processor across the backplane using Input Image and Output
Image operations. Data is transferred from the module to the processor using the
Input Image blocks, and data is transferred from the processor to the module
using Output Image blocks.
The following illustration shows the data transfer method used to move data
between the CompactLogix or MicroLogix processor, the MVI69-DFNT module,
and the Ethernet Network.
Server
Driver
Logic
Client
Driver
Logic
DFNT Module
To Ethernet
Network
Ladder Logic
Transfers Data
from module’s
Input Image to
data areas in the
processor
User Data Files
Processor
Ladder Logic
Transfers Data
from Processor
data areas to
Output Image
Input Image
Data Block
Output Image
Data Block
Status
Read Data
Write Data
TCP/IP
Stack and
Ethernet
Interface
Module’s
Internal
Database
Command Control
As shown in the diagram, all data transferred between the module and the
processor over the backplane is through the Input Image and Output Image
blocks. Ladder logic must be written in the CompactLogix or MicroLogix
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 0
Register Data
3999