Micromod MOD: Extended Modbus (XModbus) OPC Server Users Guide - Manual (Page 3)

1 Introduction
1.1 Introduction
Extended Modbus OPC Server is an Industrial IT enabled software product. It is an OPC
Foundation compliant server application (serial communications device interface) that
allows hardware devices to communicate with OPC Clients such as ABB Operate IT
Products and other software manufacturer's HSI packages like ICONICS’ Genesis32,
Intellution's FIX Dynamics and similar packages from Wonderware, CI Technologies and
others. For client software packages that are not OPC compliant, the server also supports
dynamic data entry (DDE) type links. ViZapp, Visual Application Designer, is also an
OPC Client that can use this OPC server to communicate with the devices it configures.
The OPC server handles the reading and writing of the device data. See Overview of OPC
based configuration for steps involved in configuring the client and server.
This OPC server supports MODCELL and MOD 30ML devices using Extended Modbus
as well as generic Modbus devices such as the MODCELL 2050 and the Commander
controllers and recorders including: C100, C200, C250, C300, C310, C500, C1900, L150,
L160, PR100, PR250, and MR250.
The server is used to build the tag database that contains information about the tags such
as tag name, address, device (instrument) from which they are coming and communication
port settings. Any OPC Client application, such as OPC based HMI Software, can plug
and play with this and present the data to the user.
An OPC Client is included in the ABB Extended Modbus OPC Server. This monitor client
is useful for viewing live data and determining if configured tags are receiving correct
data from the hardware.
1.2 Definitions
1.2.1 Standard Modbus Protocol
Standard MODBUS supports single-register, 16-bit integer values. ABB Commander
series instruments and the Modcell 2050 use this protocol. Modcell and MOD30ML
floating-point data may be converted to this format with ML blocks. For maximum
resolution, specify an actual engineering-unit range in the ML block. If the engineering
range is greater than 65535, a scaled range must be selected. Some standard MODBUS
drivers may be capable of reading floating-point data, using a 32-bit two-register format.
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