ProSoft Technology MVI56E-DNPNET User Manual
Page 106

Contents
MVI56E-DNPNET ♦ ControlLogix Platform
User Manual
DNPNET Ethernet Client/Server Communication Module
Page 106 of 140
ProSoft Technology, Inc.
February 13, 2015
The diagram above shows how the DNPNET database is structured according to the
configured point counts as named in firmware. Only the PLC and IED data sections are
shared with the PLC.
The sections in parentheses are for data pass through only; not to be shared with the PLC.
Data is shared with the PLC 240 words per block. Blocks are numbered 1 - 203. Block 1
transfers the first 240 words; block two transfers the next 240 words; etc., of PLC and IED
data only.
The PLC and IED data are packed and unpacked into/from blocks contiguously. Block
number assignments are independent of the point count assignments. Only the data with
point counts that end in PLC and IED (not the ones in parentheses) get packed into blocks
to be shared over the backplane with the PLC.
The block transfer logic transfers the database by packing blocks to their fullest payload until
the end of the database is reached. There are no specific block number assignments to
each variation.
This contiguous packing of PLC data necessitates a block numbering scheme that is not
specific to the individual variations -- data blocks are numbered according to the 240 word
(block payload) offset of the PLC and IED data to be shared with the PLC.
Block Description
Block ID Assignments
PLC and IED Database
Transfer Blocks
1 through 203
Status Block
300
DNP Output Initialization
Blocks
1000 through 1022
IED Input Initialization Blocks
1100 through 1193
Configuration Data
9000 through 9099
4.3.1 Normal Data Transfer
Normal data transfer includes the paging of the user data found in the module’s internal
databases between the module and the controller. These data are transferred through read
(input image) and write (output image) blocks.
Refer to the Installing and Configuring the Module section for a description of the data
objects used with the blocks and the ladder logic required. Each data block transferred
between the module and the processor has a specific block identification code that defines
the data type contained in the block.
The following table lists the block identification codes used for data transfer by the module.
DNP 3.0
Ethernet Data
Point Type
Range
DNP_Outputs
Binary Outputs
0 to 8000 points (500 16-bit words)
16-bit Analog Outputs
0 to 5000 points (if all other DNP Outputs are
0)