All posts by Avinash

About Avinash

Avinash Gupta is solely focused on free and high quality tutorial to make learning embedded system fun !


Obstacle Sensing Walking Stick for Visually Impaired Persons

This project is designed to guide a visually impaired person to walk and avoid bumping into obstacles. Low cost ultrasonic rangefinders along with a microcontroller is used to measure the distance to obstacles and if they are close enough provide a feedback to the user in form of beeps or vibrations. The project is made on a small single layer PCB. The sensors are not mounted on the PCB but they are mounted on front of the stick and connected to the main board using wires. All the parts of project PCB is shown in the image below. Read more … Pages Introduction and Usage Block Diagram Schematic and BOM PCB Layout Details of the Sensor Program and it’s Explanation

GSM Based Projects Buyer’s Guide

Today the market is flooded with so called project guidance institutes who provide ready made projects to the students of engineering. Over hyped and flashy names are the characteristics of such projects. I am writing this for the guidance of both students who are planning to buy such things or the faculty members of the collages evaluating such projects. Below I am giving some simple tests that could help you judge how well the software is developed. Start up the system with GSM Module disconnected from the MCUs Rx and Tx line and check if the system is able to detect this fault. Start up the system without inserting a SIM card, and check if the system is able to tell you the exact problem. Use a SIM card which has NO balance and SMS pack and check if the system is able to tell you weather message sending failed or not. Check if the system is able to detect presence of network before sending message. Faculty members of collage should arrange a mobile blocker, turn it on and then boot the system. If the system is designed to receive the message, try sending more that 32 SMS to the system to make the SIM memory full and then check what happens. A properly designed system should delete the messages […]


Interfacing MMA7455 I2C Accelerometer with AVR ATmega8

This article on Digital Wizard describes everything about interfacing MMA7455 I2C accelerometer with an AVR ATmega8 MCU. A C library compatible with Atmel Studio 6 is also provide with step by step instructions to get it properly installed in your new AS6 project. Each function in the library is also explained in details. Finally we make a demo program to show raw acceleration readings for each axis on a LCD. Read more …


Relays, Introduction, Working and Interfacing

Relays are very interesting and useful electronic component. They are a kind of switch, like those we use everyday in our home and offices to turn on and off electrical devices like bulbs, TVs, fans etc. The function of relay is to control the switching of a relatively heavier load which demands high voltages (like 240 V AC mains) or high current, from a relatively low voltage control signal (like 5v or 12v) Relays, an Introduction Working of Relays Interfacing of Relays with Microcontrollers Pinouts of common relays Relay Interface with AVR ATmega8 Relay Interface with AVR ATmega16


Transformers, an Introduction

Transformers are at the heart of power supply units for any electronic device that is to be powered from household wall power plugs. They help step down the higher voltages to lower voltages suitable for electronic circuits inside the devices. Read more …


Breadboard, an Introduction

Breadboards part of very advance method of building test circuit. They don’t use soldering and due to this some times they are called a solderless breadboard. Ability to make circuits without soldering is also useful for beginners who don’t know how to solder or yet they have not mastered the art of soldering. They are most useful for kids, because sometimes we don’t want them to be playing with a hot soldering iron. Learn more about breadboard


General purpose PCBs, an Introduction

General purpose PCBs, as their name suggests is the generalised from of PCB. By generalised we mean that we are free to make any kind of circuit as we wish using this PCB. This makes it useful for small scale production of electronic devices and also for testing out new ideas before production. Read more


PCBs (Printed Circuit Boards), an Introduction

An electronic device is made by using several components like ICs, transistors, diodes, capacitors, resistors, displays, indicators, switches, buttons, connectors etc. All these are connected to other components according to a schematic. A printed circuit board helps hold all components of a device in one place as a single unit and at the same time provide required electrical connection between pins of components. Read more …

Techniche offers delight for students from North-east

The first day at Techniche, the annual techno management festival of IIT Guwahati has filled the audience and participants from various colleges in Northeast and nationwide with lots of fun and rich experience in technology and management related events. The day started with various events like Workshops, Lecture series, exhibitions and finished with nites and drum circle show. In the morning, there were the nationwide prelims of Escalade, a pole climbing robotics competition where students from 12 cities all over the nation participated to test their robotics temperament. From Guwahati and adjacent areas, there were 50 teams out of which 6 teams were selected for the final round. This was followed by exhibitions by The Northeast frontier railway. In parallel, the first rounds of Junkyard wars & Techscribe and the prelims of Bermuda Triangle under Predef module occurred. The events are team based and require proper planning and coordination between the team mates. The Best Manager and Case study competitions were offered by Corporate Module on Day1. The participants, fully clad in Business attire, were trying to impress the judges and outsmart their peers. The Day1 lecture series line-up included Bikas Sinha the Homi Babha Chair Professor, Kota Harinarayan the father of India’s Tejas programme and Peter Atkins, the author of well-known series of Chemistry books. There were greeted by […]

Techniche festival kick-starts in IIT Guwahati

The sixteenth edition of the annual techno-management festival of IIT Guwahati-Techniche is back with a bang and a greater zeal and enthusiasm. Enthusiasts poured in from different areas of the country to witness this grandeur and a celebration of technology. Students came from over 180 different colleges all over India. The event started with an opening ceremony in the institute auditorium which was decorated by all the dignitaries of IIT Guwahati. Speaking of the importance of such activities in students’ life, the Director said  “Such events foster overall development of the students. Apart from their regular workload, it is great to spend some time to enrich their technical and competitive skills on a national platform. This would be a huge benefit for the students of North-east”. There are many challenging events lined up for the rest of four days and he urged all the college students to pour into IIT Guwahati campus to witness and be a part of this technical extravaganza. Following this was the rock-on concert by the VH1 group which bought in the much needed enthusiasm to keep up for the rest of the days. Liquid drumming was the other event where performers showed their expertise in the fields of drumming and rock bands. Sand painting was the best amongst the events where the audience were nothing […]