ProSoft Technology MVI46-DFNT - Manual (Page 76)

Reference MVI46-DFNT ♦ SLC Platform
User Manual EtherNet/IP Client/Server Communication Module
Page 76 of 177 ProSoft Technology, Inc.
October 12, 2010
The DFNT module supports server functionality using the reserved ControlNet
service port 0xAF12. Services supported in the module permit client applications
(that is, RSView, ControlLogix processors and RSLinx) to read from and write to
the module’s database. This document discusses the requirements for attaching
to the module using several client applications.
The following illustration shows the relationship of the DFNT module’s
functionality to devices on an Ethernet network:
Server functionality places all data transfer operations outside the module. There
is no configuration required in the module other than setting up the network and
database parameters in the configuration file. Ladder logic in attached
processors use MSG instructions to perform read and write operations on the
module’s internal database.
When RSLinx links a user application to the module, the module’s server
functionality must be used. RSLinx exists on an Ethernet network only as a client
application. It cannot act as a server. User applications can use the DDE/OPC
capabilities built into RSLinx to interface with the data in the DFNT module.
RSView can link directly to the module using drivers supplied by RSLinx.
The internal database of the DFNT module is used as the source (read requests)
and destination (write requests) for requests from remote clients. Access to the
database depends on the MSG command type executed to interface with the
database. The following table defines the relationship of the module’s internal
database to the addresses required in the MSG instructions: