ProSoft Technology MVI69-DNP User Manual

Page 77

Reference MVI69-DNP

♦ CompactLogix or MicroLogix Platform

DNP 3.0 Master/Slave Communication Module

ProSoft Technology, Inc.

Page 77 of 129

November 3, 2008

This sequence will continue until interrupted by other write block numbers sent by
the controller or by a command request from a node on the DNP network or
operator control through the module's Configuration/Debug port.

The following example shows a typical backplane communication application.

Write Block

These blocks of data transfer information from the CompactLogix or MicroLogix
processor to the module. The structure of the output image used to transfer this
data is shown below:

Offset Description

Write Block ID

1 to 60

Write Data

61 Spare

The Write Block ID is an index value used to determine the location in the
module's database where the data will be placed as defined in the table
presented in the previous section. Each transfer can move up to 60 words (block
offsets 1 to 60) of data.

5.2.3 Command Control Blocks

Command control blocks are special blocks used to control the module or
request special data from the module. The current version of the software
supports several command control blocks, each of which are discussed in the
following topics.

Block 9901 - Event Command

This block issues one or more command control requests to slaves attached to
the DNP master port for object 12 data. When the module receives a block 9901
identification code, it places the included commands into the command queue.

Block Format for Write

Word Offset in Block Data Field(s)

Description

0 Block

This field contains the block identification code of
9901 for the block.

1 Command

Count

This field defines the number of CROB blocks to
generate. The valid range for the field is 1 to 6.

2 to 11

Command #1