Implementation of an IIoT Access Gateway for the ModBusE – Modbus Extension using BeagleBone Black

Abstract

The implementation of this Industrial Internet of Things (IIoT) gateway for the ModBusE protocol aims to improve the data flow at the level of slots and acquisition cycle, using microcontroller’s architectures. In this paper, the gateway implementation is performed using a BeagleBone Black board. BeagleBone Black uses the Sitara AM335x processor from Texas Instruments. This processor consists of a 32 bit ARM Cortex A8 processor that operates at a frequency of up to 1 GHz and two 32 bit PRU (Programmable Real-Time Units) processors that operate at a frequency of 200 MHz. The acquisition cycle of the ModBusE protocol based on a client-server (master-slave) architecture will be implemented on one of those two PRU processors. The high power ARM Cortex A8 processor can be used to implement OPC UA server and client. The aim is also to develop a specific AM335x Sitara driver that allows fast transfer between the two processors (PRU – ModbusE client / server and Cortex A8 - OPC UA server and client). This paper proposes the general structure of an IIoT gateway that makes the connection between the physical environment using devices connected through the ModBusE protocol and the upper levels of IIoT through OPC UA.