ProSoft Technology MVI46-DFNT - Manual (Page 30)

Configuring the MVI46-DFNT Module MVI46-DFNT ♦ SLC Platform
User Manual EtherNet/IP Client/Server Communication Module
Page 30 of 177 ProSoft Technology, Inc.
October 12, 2010
2.4 [DFNT Client x Commands]
This section defines the EtherNet/IP commands to be issued from the module to
server devices on the network. These commands can be used for data collection
and/or control of devices on the TCP/IP network.
2.4.1 Command List
In order to interface the virtual database with DF1 slave devices, you must
construct a command list. The commands in the list specify the DF1 slave device
to be utilized, the function to be performed (read or write), the data area in the
device to interface with and the position in the virtual database to be associated
with the device data. There is a separate command list for each DF1 master
device emulated. The list is processed from top (command #0) to bottom. A poll
interval parameter is associated with each command to specify a minimum delay
time between the issuance of a command. If the user specifies a value of 10 for
the parameter, the command will be executed no more frequently than every 10
seconds for the serial implementation and 1 second for the network
implementation.
Write commands have a special feature, as they can be set to execute only if the
data in the write command changes. If the data in the command has not changed
since the command was last issued, the command will not be executed. If the
data in the command has changed since the command was last issued, the
command will be executed. Use of this feature can lighten the load on the DF1
network. In order to implement this feature; set the enable code for the command
to a value of 2.