MODBUS_PLUS Overview

MODBUS® Protocol is a messaging structure developed by Modicon in 1979, used to establish master-slave/client-server communication between intelligent devices. It is a de facto standard, truly open and the most widely used network protocol in the industrial manufacturing environment.. It is literally implemented by hundreds of vendors on thousands of different devices in order to transfer discrete/analog I/O and register data between control devices. It's really a lingua franca or common denominator between different manufacturers.

MODBUS® has become a de-facto standard since its introduction to the market in 1979, and is being used in multiple master-slave applications. MODBUS® is used to monitor and program devices; to communicate intelligent devices with sensors and instruments; to monitor field devices using PCs and HMIs; MODBUS® is also an ideal protocol for RTU applications where wireless communication is required, being that the reason of why it is used in uncountable Gas and Oil and substations applications. But MODBUS® is not only an industrial protocol; Building, infrastructure, transportation and energy applications are also making use of its benefits.

Note that the IDX Modbus interface group is divided according to the following interfacing functionality:

·      DM_MODBUS_PLUS: A SA85 Modbus Plus implementation.

·      DM_MODBUS_PLC: A TCP/IP Modbus implementation (PLC side).

·      DM_MODBUS_TCP: Used for TCP/IP-based Modbus interfacing.