beautypg.com

ProSoft Technology MVI56E-MCMR User Manual

Page 87

background image

MVI56E-MCMR ♦ ControlLogix Platform

Configuring the MVI56E-MCMR Module

Modbus Communication Module with Reduced Data Block

User Manual

ProSoft Technology, Inc.

Page 87 of 225

May 13, 2014

Value

Description

Float Start

Register offset in message for floating data point. See Floating Point
Data Handling for more information (page 87).

Float offset

Internal address for floats

Internal Slave ID

Valid values are 1 to 247

Minimum Response Delay

0 to 65535 milliseconds to delay before response

Bit Input Offset

Defines the starting address within the module for 1x Modbus
addressing. A value of 0 sets 10001 to 10016 as address 0 in the
MVI56E-MCMR module.

Word Input Offset

Defines the starting address within the module memory for 3x
registers.

Output Offset

Defines the starting address within the module for 0x coils.

Holding Register Offset

Defines the starting address within the module for 4x addressing.

Use Guard Band Timer

Y

ES

or N

O

Packet gap timeout for messages

Guard Band Timeout

0 to 65535

A value of 0 uses the default baud rate, or you can set a timeout value
in milliseconds.

2.4.4 Floating-Point Data Handling (Modbus Slave)

In most applications, the use of floating-point data requires no special handling.

1 Copy the data to and from the MVI56E-MCMR module with a tag configured

as a data type REAL in the ControlLogix processor.

Each floating-point value will occupy 2 registers on the Modbus network.
Some Master devices use Enron or Daniel Float data. These types of floats
require one Modbus register for each float in the module memory. If your
Master requires this addressing, refer to the following section.
For standard floating-point data handling, the following is an example of
copying 10 floats to the module.

2 First, configure a tag within the ControlLogix processor.

3 Then configure a COP statement within the main routine to copy this tag to

the module’s MCMR.DATA.W

RITE

D

ATA

array.

The length of the copy statement is determined by the Dest file size. To copy 10
floats from the MCM_Write_Floats array to the MCMR.DATA.W

RITE

D

ATA

array,

the length of the COP statement must be set to a value of 20.