ProSoft Technology MVI69-DNPSNET - Manual (Page 80)

MVI69-DNPSNET ♦ CompactLogix or MicroLogix Platform Reference
Distributed Network Protocol Interface Module
Page 80 of 119 ProSoft Technology, Inc.
November 3, 2008
Data tags in the CompactLogix or MicroLogix processor contain the data to be
used by the module and the configuration information is stored in the text file,
DNPSNET.CFG, stored on the module's Compact Flash Disk. Before you
generate the program or layout the data files, you must first design your system.
Time spent doing system design at the outset of the project will greatly enhance
the success and ease of development of the project.
5.3.1 Designing the system
System design defines the data requirements of the system, communication
parameters, and module functionality. The application developer should refer to
the person responsible for the DNP master and slave device configurations to
verify that the functionality and data types required for the whole system are
consistent. Review the DNP Device Profile and DNP Subset documentation for a
definition of the level of DNP support offered by the module.
The following topics describe each element of system design.
Data Requirements
This phase of design defines what data elements are to be interfaced in the
CompactLogix or MicroLogix processor with the DNP master. The module
provides the following data types: digital input, digital output, counter, analog
input, analog output, float input and float output. All communications between the
DNP master and the PLC is through these data types. Therefore, all data to be
used by the system must be contained and configured in one of these data types.
The following illustration shows the databases maintained by the module for the
DNP data.
DATA AREA
BINARY INPUTS
ANALOG INPUTS
FLOAT INPUTS
COUNTER DATA
BINARY OUTPUTS
ANALOG OUTPUTS
DNP DATA
FLOAT OUTPUTS
FROZEN DATA FROZEN COUNTER DATA
BINARY INPUTS
ANALOG INPUTS
LAST VALUE DATA
FLOAT INPUTS
BINARY INPUT EVENTS
ANALOG INPUT EVENTS
EVENT DATA
FLOAT INPUT EVENTS
The module is responsible for maintaining the databases using data acquired
from the PLC and DNP master attached network port.