3 rd International Conference on Multidisciplinary Research & Practice Page | 74 Volume IV Issue I IJRSI ISSN 2321-2705 Design and Development of a Programmable Logic Controller Using Atmel Controller and MATLAB Simulink Priyam Parikh # , Himanshu Singh * , Selva Kumar Nadar $ # Assistant Professor, Mechatronics Department, SAL College of Engineering *$ UG Student, Electronics & Communication Engineering, Department, Amiraj College of Engineering & Technology Abstract— This document shows an in-depth introduction into programmable logic controllers (PLCs) interfaced with matlab for better and easier task fulfilling operations in an industry. This article starts with an overview of the history and the role PLCs in factory automation. Keywords— PLC, Relay Unit, MATLAB hardware support package, Serial Communication, ATMEL Controller, MATLAB, motors, encoder I. INTRODUCTION PLC is digital operating electronic apparatus which uses a programmable memory for internal storage of instruction for implementing specific function such logic, sequencing, timing, counting and arithmetic to control through analog or digital input/output modules various type of machines or process. The core modules of an industrial-control system are examined: the analog input function, analog output functions, the distributed control (fieldbus) interface, digital inputs and outputs (I/Os), the CPU, and isolated power[2] . Fig. 1 Block diagram of a typical plc This document shows the design of a controller based PLC which would have 8 channel I/O and 6 channel analog Input. The system would have an AVR micro-controller and would also have relay cards to interface motors like DC, stepper, servo and AC motors too. Here Software MATLAB (Simulink) is used to establish a serial communication with the PLC which is much easier than writing a machine language program. One can program this plc by just placing the desired blocks into it.[7] A. Methodology This document explains how the actual plc works. First, the plc is programmed normally by developing an algorithm for the plc to work in the MATLAB hardware support package and feed it to the plc using inbuilt I2C or SPI. [1] Now as the plc is ready to use the hardware connections for the desired task is to be done. External power is required to power the relay cards and also the plc. If not, the plc can be given the power supply using usb cable connected to the algorithm developing device.[3] B. Objectives The main objectives of the project are as follows:  Reduce programming time.  Free up more memory in the controller compared to code feeded controller.  Easy and quick interface.  I/O ports interface and access as needed.  Multiple output run simultaneously. C. Arduino This section explains about the heart of the plc prototype. This prototype contains the microcontroller based prototyping open source platform called “Arduino” which also uses Atmel controller. It connects to a computer via a USB cable, and is programmed using it with a language similar to C++.[4]-[6] The Arduino has a number of input ports which can be used to read in signals from other circuits or devices, and output ports which can be used to drive external lights, speakers, motors etc.[8] A