ProSoft Technology MVI56E-MNETC User Manual page 117

MVI56E-MNETC/MNETCXT ♦ ControlLogix Platform
Modbus TCP/IP Client Enhanced Communication Module - Client/Server
1 The routine polling process is temporarily interrupted.
2 The commands in the command priority queue are executed until the queue
is empty.
3 Then the module goes back to where it left off on the MNET Client x
Command List and continues routine polling.
Event Command blocks send Modbus TCP/IP commands directly from controller
tags by ladder logic to the Client command priority queue on the module. Event
Commands are not placed in the module's internal database and are not part of
the MNET Client x Command List.
Block 4000 is functionally identical to Block 2000 with the addition of the Event
Command Sequence Number parameter.
Block Request from Processor to Module
Word Offset
0
1 to 4
5
6
7
8
9
10
11
12
13 to 247
The module will use the parameters passed in this block to construct the
command.

The IP Address for the destination server to reach on the network is entered
in four registers (1 to 4). Each octet value (0
server's IP address is placed in one of the four registers For example, to
interface with node 192.168.0.100, enter the values 192, 168, 0 and 100 in
registers 1 to 4.

The Service Port field selects the TCP service port on the server to connect.
If the parameter is set to 502, a standard MBAP (Modbus API for network
communications) message will be generated. All other service port values will
generate a Modbus command message encapsulated in a TCP/IP packet.

The Slave Address is the Modbus node address for the message.

The Internal DB Address parameter specifies the module's database location
to associate with the command.

The Point Count parameter defines the number of points or registers for the
command.

The Swap Code is used with Modbus functions 3 and 4 requests to change
the word or byte order.
ProSoft Technology, Inc.
September 20, 2018
Description
4000 to 4029 (last digits indicate which Client to utilize)
IP Address
Service Port
Slave Address
Internal DB Address
Point Count
Swap Code
Modbus Function Code
Device Database Address
Event Command Sequence Number
Spare
Length
1
4
1
1
1
1
1
1
1
1
235
255) of the destination
TO
Reference
User Manual
Page 117 of 172