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MVI56E-MNETR ♦ ControlLogix Platform
Reference
Modbus TCP/IP Interface Module with Reduced Data Block
User Manual
ProSoft Technology, Inc.
Page 127 of 175
June 14, 2011
Client Driver
In the Client driver, the MVI56E-MNETR module issues read or write commands
to servers on the Modbus TCP/IP network. These commands are user configured
in the module via the Client Command List received from the module's
configuration or issued directly from the ControlLogix processor (Event
Command). Command status is returned to the processor for each individual
command in the command list status block. The location of this status block in
the module's internal database is user-defined. The following flowchart describes
the flow of data into and out of the module.
1
The Client driver obtains configuration data when the module restarts. This
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 Modbus TCP/IP network.
2
When configured, the Client driver begins transmitting read and/or write
commands to the other nodes on the network. The data for write commands
is obtained from the module's internal database.