Introduction to the Simple Modbus Driver

This driver is a simple driver. It provides additional functionality to enable Geo SCADA Expert to interface with specific supported devices using a particular protocol. To interact successfully with such devices, you need to:

Intended Audience

This guide is primarily intended for engineers who are responsible for configuring Modbus items and features in the Geo SCADA Expert database.

The guide also contains information for:

Document Scope

This guide explains the configuration, features and database items that are specific to Geo SCADA Expert’s Simple Modbus driver. The Simple Modbus Driver allows a Geo SCADA Expert system to be populated with data from, and control points on, Modbus Slaves or Modbus PLCs. The driver provides extra functionality within the server for retrieving data from, or controlling points on, Modbus devices. For example, Modbus PLCs use registers to store point data. Properties used by the Simple Modbus driver determine the location of the data within those registers (see Modbus Register Ranges). Function codes supported by the Simple Modbus driver determine how it reads or writes data to those registers (see Modbus Function Codes Supported by the Geo SCADA Expert Simple Modbus Driver).

For information on how to configure Geo SCADA Expert to act as a Modbus PLC and report any data changes back to its Master, see the Geo SCADA Expert Guide to the Modbus Slave Driver.

The Modbus documentation explains how to configure Modbus-specific features and items within the Geo SCADA Expert database, with sections on:

It also explains driver-specific features that are of interest to operators, such as:

and driver-specific aspects that may be of interest to system administrators and engineers when diagnosing unexpected system behavior:

Geo SCADA Expert can communicate with Modbus devices using one of several drivers—for information on which driver is appropriate for your system requirements, see Which Driver?.

Policy of Continuous Development

To maintain Geo SCADA Expert's position as a leading SCADA solution, we operate a policy of continuous development. Each new version of our product supports additional features and functionality to previous releases. To use the new drivers, features, or functionality involving database items, your system has to be running the latest version of Geo SCADA Expert software. Additionally, if you have upgraded from an earlier version of the product, you have to deactivate any Database Emulation that was activated during the upgrade process. You should only deactivate the Database Emulation once you have successfully completed the upgrade process on all of the servers and clients in your system (see Deactivate Database Emulation after a Successful Upgrade).