ProSoft Technology MVI46-DFNT - Manual (Page 79)

MVI46-DFNT ♦ SLC Platform Reference
EtherNet/IP Client/Server Communication Module User Manual
ProSoft Technology, Inc. Page 79 of 177
October 12, 2010
Client Driver
In the client driver, the MVI46-DFNT module is responsible for issuing read or
write commands to servers on the EtherNet/IP network using explicit, connected
messaging. These commands are user configured in the module via the Client
Command List received from the module's configuration file (DFNT.CFG).
Command status is returned to the processor for each individual command in the
command list status block in the command control data area. Ladder logic is
responsible for acquiring this data from the module. The following flow chart and
associated table show the flow of data into and out of the module.
Step Description
1 The client driver obtains configuration data from the DFNT.CFG file when the module
restarts. The configuration data obtained includes the timeout parameters and the
Command List. These values are used by the driver to determine the type of commands
to be issued to the other nodes on the EtherNet/IP (see Module Configuration).
2 After configuration, the client 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 the module's internal database to build the command.
3 Presuming successful processing by the node specified in the command, a response
message is received into the client driver for processing.
4 Data received from the node on the network is passed into the module's internal
database, assuming a read command.
5 Status data is returned to the SLC processor for the client and a Command List error
table can be established in the module's internal database. This data is requested using
the command control data area and is a responsibility of the ladder logic.
The Module Setup section provides a complete description of the parameters
required to define the client.