Reference MVI56-DNP
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ControlLogix Platform
User Manual
DNP 3.0 Server
Page 106 of 171
ProSoft Technology, Inc.
July 21, 2011
Master Driver Mode
In the Master mode, the MVI56-DNP module issues read or write commands to
slave devices on the DNP network. These commands are user configured in the
module via the Master Command List received from the ControlLogix processor
or issued directly from the ControlLogix processor (Special Function). Command
status is returned to the processor for each individual command in the command
list status block. The following flow chart and associated table describe the flow
of data into and out of the module.
Step Description
1
The Master driver obtains configuration data from the DNP.CFG file. The configuration
data obtained includes the Master Slave and Command Lists. These values are used by
the Master driver to determine the type of commands to be issued to the other nodes on
the DNP network.
2
After configuration, the Master driver begins transmitting read and/or write commands to
the other nodes on the network. If writing data to another node, the data for the write
command is obtained from one of the module’s internal databases to build the command.
3
Presuming successful processing by the node specified in the command, a response
message is received into the Master driver for processing.
4
Data received from the node on the network is passed into the module’s appropriate
internal database, assuming a read command.
5
Status is returned to the ControlLogix processor for each command in the Master
Command List.