Implementation of Digital Circuits using the Internet of Things

Digital circuits are used everywhere in day to day lives. There is a need to learn it practically by every undergraduate in laboratories. Digital trainer kits are being used in laboratories which use a basic circuit connection approach. Only this approach is not sufficient for a student to explore deep enough because digital circuits can be implemented by any number of approaches. A smart approach is required for enhancement of the trainer kit. This project incorporates the Iot approach required for implementation of digital circuits. This project works as a digital demo kit which helps students to smartly learn boolean functions with the Iot approach. Arduino microcontroller is a substitute for digital circuits and it brings smartness and digital logic in one platform to easily achieve the required digital functionality. In this project, implementation of logic gates, basic combinational and sequential circuits will be done. This project uses Arduino programming which is executed with respect to digital circuits. The inputs are given using ultrasonic sensors, input parameters are given efficiently using the bluetooth module and the outputs will be shown on a two bit seven segment display. Trainer kits can be fabricated using this mechanism and components and thus, it would definitely find a good application in laboratories helping undergraduates to learn in a better manner.


INTRODUCTION
Logic Gates are the building blocks of digital logic design. The arrangement of these gates in various models provides solutions in an appropriate manner to the complex problems. Nevertheless, there are challenges which pose a threat to digital circuits [1]. A part of a digital integrated circuit may misbehave due to thermal effects i.e. it may burn resulting in the failure of IC [2]. So, the replacement of the failed part is a challenge. It is not easily available in the market. Hence, there is a need to reproduce the functionality of the failed part using circuit diagrams and experience [3]. This replacement can be done using flexible components like Arduino. The present work focuses on replacing the logic gate integrated circuits with programmed Arduino with desired functionality.

RELATED WORK
Since digital trainer kits are already in use for many years, this work is an upgrade or an innovative version of it based on the emerging technologies.The desired digital functions are given using a bluetooth controller app installed in mobile. Arduino knows via bluetooth connection what digital function to implement. And based on the provided inputs it runs and displays the output on the seven segment display. Here, ultrasonic sensors are used to know what inputs are provided for the digital circuit.

MATERIALS
In this work, components like Arduino Uno board, ultrasonic sensors, one and two bit seven segment displays were used along with bluetooth module and jumper wires supported by cardboard sheets providing a platform for the connection of these components.

EXPERIMENTAL RESULTS AND DISCUSSION
The bluetooth controller app is installed on mobile to command the Arduino which digital function to be implemented. The input is given to the bluetooth module which is connected to Arduino. The Arduino receives the desired digital function which is to be implemented.     The Arduino program is compiled and runned in Arduino software and then uploaded to the Arduino board. If an object is present in front of the sensor, the input is considered '1' otherwise it's considered '0'. Left sensor detects the first bit (MSB) and the right sensor detects the second bit (LSB). Based on the provided inputs through bluetooth connection and sensors, the program is executed and the output is shown on the display. Various digital logic functions have been implemented such as the seven logic gates and combinational circuits as of now.

CONCLUSION
In this project, it would be concluded that an embedded system can be used as a digital circuit. Implementation of digital functions in a smart approach can only be done by an embedded system comprising sensors. In spite of being not an application oriented project, the mechanism is almost similar to that of an application oriented project. There would only be a slight change in outputs. In this project, the outputs are nothing but digital numbers '0' and '1' whereas the outputs can be like rotating a motor or switching lights for an application oriented project. This project will be applicable in an indirect manner through the use of the mechanism or software program.

ACKNOWLEDGEMENT
We would like to thank Assistant Professor Dr.G.Anitha and Associate Professor Dr.K.Sridevi for guiding and providing necessary resources.