MVI56-MCM Modbus Master/Slave Communication Module网络交换模块

the Modbus network.

Many host SCADA packages support the Modbus

protocol, while devices commonly supporting the

protocol include several PLCs, as well as many other

third party devices in the marketplace. (For a partial list

of devices that speak Modbus, please visit the ProSoft

Tested section of the ProSoft Technology web site).

General Specifications

• Single Slot – 1756 backplane compatible

• Local or remote rack

• The module is recognized as an Input/Output

module and has access to processor memory for

data transfer between processor and module

• Ladder Logic is used for data transfer between

module and processor.

• Configuration data obtained through user-defined

ladder. Sample ladder file included

Functional Specifications

Some of the general specifications include:

• Support for the storage and transfer of up to 5000

registers to/from the ControlLogix processor's data

files

• Module memory usage that is completely user

definable

• Two ports to emulate any combination of Modbus

master or slave device

• Supports Enron version of Modbus protocol for

floating point data transactions.

Slave Specifications

The MVI56-MCM module accepts Modbus function code

commands of 1, 2, 3, 4, 5, 6, 8, 15, 16, 17, 22 and 23

from an attached Modbus master unit. A port configured

as a Modbus slave permits a remote master to interact

with all data contained in the module. This data can be

derived from other Modbus slave devices on the

network, through a master port, or from the ControlLogix

processor.

Master Specifications

A port configured as a virtual Modbus master device on

the MVI56-MCM module actively issues Modbus

commands to other nodes on the Modbus network. One

hundred (100) commands are supported on each port.

Additionally, the master ports have an optimized polling

characteristic that polls slaves with communication

problems less frequently. The ControlLogix processor

can be programmed to control the activity on the port by

actively selecting commands from the command list to

execute or issuing commands directly from the ladder

logic.

Additional Products

ProSoft Technology offers a full complement of