beautypg.com

ProSoft Technology MVI56-AFC User Manual

Page 70

background image

Modbus Database

MVI56-AFC ♦ ControlLogix Platform

User Manual

Liquid and Gas Flow Computer

Page 70 of 316

ProSoft Technology, Inc.

February 25, 2011

5.1

AFC Modbus Address Space

Addressable Modbus registers are divided into four banks as shown in the

following table.

MODBUS Address Space Allocation: Total Modbus Registers: 131,072

Primary Slave Banks
(131072 registers)

Virtual Slave Banks
(20,000 registers)

Holding Registers

Input Registers

Holding Registers

Input Registers

From: 0

From: 0

From: 0

From: 0

To: 65535

To: 65535

To: 9999

To: 9999


The first 100 registers of the virtual slave (registers 0 through 99) are predefined

to map to the first 100 registers of the primary slave. This mapping cannot be

changed. Also, the Virtual Slave Input Registers can be accessed as Virtual

Slave Holding Registers by adding 10000 to the Modbus register address; for

example, Input Register 2386 is the same as Holding Register 12386.

5.1.1 Accessing the Data

The AFC Manager provides an easy way to read and write data from both slaves

through the Modbus Master Interface.

This manual is related to the following products: