Tutorials

In the previous tutorial, it was discussed how arithmetic operations on binary numbers can be implemented by the means of boolean logic operations. In a digital circuit, the logic operations are executed by logic gates. A Logic gate is an electronic circuit which makes logical decisions. The AND, OR and NOT are the basic logic gates. 

In the previous tutorial, various logic gates and their construction was discussed. In the tutorial – Boolean Logic Operations, it was discussed that how by performing logical operations on binary data, arithmetic operations can be executed. In a digital circuit, many logic gates are interconnected along with registers and memory elements to carry out a complex computation task. Any computational problem can be expressed as a boolean function or boolean expression.

In the previous tutorial, various boolean postulates and theorems were discussed. These theorems and postulates are useful in deducing a boolean expression. It was also discussed that for n number of variables, there can be maximum 2^2n boolean functions. So, there can be maximum 16 (2^4) boolean functions between two boolean variables. A boolean variable represents a singular binary data source in digital electronics i.e. a single bit or serial  stream of bits. So, there can be maximum 16 logical functions in digital circuits. Let us learn about all the logical operations. 

Note: it’s recommended to follow this VHDL tutorial series in order, starting with the first tutorial. In the previous tutorial, we designed a clocked SR latch circuits using VHDL (which is a very high-speed integrated circuit hardware description language). For this project, we will: Write a VHDL program to build a D flip-flop circuit Verify the…

The audio electronics is a branch of electronics that deals with designing of circuits that convert sound into electrical signals or electrical signals back into the sound. These circuits all together form an audio system.  Basically, an audio system is designed to receive audio signals (via microphone), record audio in some storage, transmit audio (through wired or wireless communication channels) and reproduce audio signals (via speakers). So, the audio circuits perform signal processing for representing the sound in the form of electrical signals, manipulate the electrical (audio) signals like amplifying, filtering or mixing, reproduce sound from the audio signals, store audio into computer files or reproduce audio from an audio file. All these processes are performed by different audio related circuits or devices.

In the previous tutorial, sound wave and its properties were discussed. Now it’s time to understand Acoustic Waves. Generally, the term sound wave is used to refer the waves having frequency range audible to humans that is 20 Hz to 20 KHz. The waves having frequency greater than 20 KHz are called Ultrasonic waves and waves having a frequency range in Giga Hertz or higher are called Hypersonic Waves. The term Acoustic Wave is a more general term to refer sound or vibration of any frequency.   In physics, Acoustic is the branch of science which deals with the study of any mechanical wave in the solid, liquid and gaseous medium. Acoustic Waves are longitudinal waves.

In the previous tutorials, physical properties of sound waves and acoustic waves were discussed. Sound or Acoustic Waves are in the form of vibration. Sound needs to be converted into electrical signals so that it can be processed by electronic circuits. So, the sound which is a mechanical energy must convert into electrical energy and must be precisely represented as an electrical waveform (analog) for any signal processing operations.  So, there is need of a device which could sense the audio signals efficiently and convert them into electrical signals. 

In the previous tutorial, working principle and classification of microphones was discussed. The microphone is an input transducer which converts sound waves into electrical signals. The audio signals from a MIC are amplified by a preamplifier and transferred to the main audio unit. The audio unit might comprise of amplifier and/or filter circuit or may have other circuitry to store audio to a computer. The amplified or stored audio is reproduced using another type of transducer which is called speaker.  The Speaker is a type of output transducer which converts the electrical signal into audio signal. Speakers are enclosed in a rectangular or square shape cabinet. The shape of the box affects the quality of the sound. The cabinet consists of different types of transducers/speakers which produce different types of audio frequency. Each transducer is called as ‘driver’ and the whole cabinet is known as ‘loudspeaker’.

In the previous tutorials, two of the most important building blocks of an audio system – Microphone  and Speaker were discussed. An audio system is designed to receive audio signals (via microphone), record audio in some storage, transmit audio (through wired or wireless communication channels) and reproduce audio signals (via speakers).

Light sensors are widely used in electronic applications. The most common one used is a photoresistor or light-dependent resistor. Despite a long response time, this sensor is inexpensive and useful in several applications. A photoresistor consists of a zigzag track of photo-sensitive semiconductors. It offers pure resistance although this is dependent on the ambient light.…

In the previous tutorial VHDL tutorial, we designed 8×3 encoder and 3×8 decoder circuits using VHDL. (If you are not following this VHDL tutorial series one by one, you are requested to go through all previous tutorials of these series before going ahead in this tutorial) In this tutorial, We shall write a VHDL program…

In the previous tutorial VHDL tutorial, we designed an 8-bit parity generator and 8-bit parity checker circuits using VHDL. (If you are not following this VHDL tutorial series one by one, you are requested to go through all previous tutorials of these series before going ahead in this tutorial) In this tutorial, We shall write…

Having been around for more than two decades, USB connectors are one of the most popular and well-recognized interconnect components in electronic designs. From Type A to Type-C, USB has gone through an array of changes both in terms of the physical connector as well as their associated standards. USB Type-C is the most advanced…

Nowadays programming language is getting more popular and is being used in each and every domain. Various applications, software etc. are created by programming. C programming is easy and simple language,  which can prove to be a useful choice for a beginner who wants to become a programmer.C language is the basis of all languages and is useful to understand the concept of Linux in brief. Most of the part of Linux kernel is written in C language. So knowledge of C programming helps to understand Kernel program and application.

A file is everything in Linux. When a file is executed, it is understood as a process. Process is created by another process and gets destroyed after being used. Multiple processes can run on Linux system and various commands are specified for management of process.  Each process is identified by a unique number called Process-ID (PIDwhich is allocated while the process is created. from the parentPID.If you execute any single command from shell terminal, it also creates a process. Refer the tutorial Process in Linux for more information about process.Here I will explain various process commands which  give out the information about running process.

Linux supports both GUI (Graphical User Interface) and CLI (Command Line Interface) environments. GUI is more user friendly for users and it’s easy to point, click and drag without any confusion. You can create folder, file and various operations as per your need and work upon them like window operating system. Traditional UNIX environment supports CLI but not GUI. Command Line Interface is a terminal where you can enter the command to tell computer what to do. You can create file, folder and various operations by entering command in CLI terminal and it is faster and more powerful than GUI. Various Linux distributions make use of similar commands. You need to read various commands before working in Linux with CLI.

This tutorial explains how to install and run Arduino in Linux distribution such as an Ubuntu. Arduino is already available in the software center of Ubuntu which is one of the repositories of Linux. Ubuntu needs to meet the required dependencies of Arduino. so before installibng Arduino make sure that the dependencies are met.Arduino software is made in java environment  and to run the java program, we need to download and install Java run time environment. There is no need of installing java run time if it is already installed in your system.. Since Arduino software already includes java you can install  it individually from Ubuntu software center using the following command line from command terminal: Ubuntu needs to meet the required dependencies of Arduino. so before installibng Arduino make sure that the dependencies are met.

Now that we know the basics of Brainwaves and the sensor on which we are working, it’s time to learn about the brain of this brain wave sensor. The main part of any device is its processing part and in the case of Mindflex Sensor, it’s the NeuroSky EEG Chip.Let’s move on to the details so as to know what the chip contains and how does it work.

Note: it’s recommended to follow this VHDL tutorial series in order, starting with the first tutorial. In the previous tutorial VHDL tutorial – 11, we learned how to design half and full-subtractor circuits by using the VHDL. In this tutorial, we will: Write a VHDL program to build an 8-bit parity generator and checker circuits Verify…

Note: it’s recommended to follow this VHDL tutorial series in order, starting with the first tutorial. In previous tutorial VHDL tutorial – 10, we had designed half and full-adder circuits using VHDL. In this tutorial, we will: Write a VHDL program to build half and full-subtractor circuits Verify the output waveform of program (digital circuit) with…