John Hopkins

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Adventures in Science: Level Up Your Arduino Code With Timer Interrupts

Name<p>Size<p>Possible Interrupts<p>Uses in Arduino<p>Timer0<p>8 bits<br>(0 - 255)<p>Compare Match<br>Overflow<p>delay(), millis(), micros()<br>analogWrite() pins 5, 6<p>Timer1<p>16 bits<br>(0 …

Arduino

Learn Regular Expressions - Lesson 1: An Introduction, and the ABCs

<i>Regular expressions</i> are extremely useful in extracting information from text such as code, log files, spreadsheets, or even documents. And while …

Typography

Top 10 Tips for Professional Schematic Design | EAGLE

<i>This engineer deserves a medal for his schematic organization! (Image source)</i><p>If your schematic isn’t large enough to require separate sheets for each …

Microcontroller

All The Stuff You Wished You Knew About Fourier Transforms But Were Afraid To Ask

The Fourier transform underpins so much of our technological lives, in most cases probably without our realising it. The ability to mathematically …

Mathematics

Most useful BASH commands to master

“The problem with being self-taught is that you seldom know what it is you don’t know.” --a wise Autodidact. Recently, the my boss introduced me to …

Linux

How to access/view Python help when using vim - nixCraft

I am a new Vim text editor user. I am writing Python code. Is there is a way to see Python documentation within vim and without visiting the …

Linux

How to reload .vimrc file without restarting vim on Linux/Unix - nixCraft

I am a new vim text editor user. I usually load ~/.vimrc using:vs ~/.vimrcfor configuration. Once edited my .vimrc file I need to reload it without …

Linux

FTDI ESP8266 Definitive Wiring

Introduction: FTDI ESP8266 Definitive Wiring<p>If you wish to use the cheap ESP8266 ESP-01 module without the nuisance of having to press buttons or …

Arduino

#58 ESP8266 Sensor runs 17 days on a coin cell/transmits data to sparkfun.com and ubidots.com

Microcontroller

ESP8266 ESP-01 Low Power Mode – run it for months

Amazing <b>ESP8266 ESP-01</b> WiFi boards have pretty irritating problem: theirs power consumption is pretty high. Minimal power consumption of about 70mA …

Microcontroller

IFTTT Smart Button

Things used in this project<p><b>Hardware components:</b><p>Everything ESP ESP8266 ESP-01<p>×<p>1<p>Buy from Newark Element14<br>• Buy from MCM Electronics<p>1N4001 Diode<p>×<p>1<p>Resistor …

Microcontroller

ESP8266 Projects

The Button - a WiFi connected push button<p>The button is one of those project that is easy to make and useful in more ways than I can count. The idea …

Arduino

Arduino Motion Detector + Make It Wireless + Call Phone When Motion Detected

Introduction: Arduino Motion Detector + Make It Wireless + Call Phone When Motion Detected<p>I have always wanted a motion sensor system at my<br>house but …

Arduino

Arduino / ATmega 328P fuse settings

« SSH Kung Fu »

27 April 2014<p>OpenSSH is an incredible tool. Though primarily relied upon as a secure alternative to plaintext remote tools like telnet or rsh, …

How to Change Fuse Bits of AVR Atmega328p - 8bit Microcontroller Using Arduino

The AVR AtmegaXXX microcontrollers comes with a default 1 MHz internal oscillator. In this instructable I will show you how to change the fuses of …

Developing for the Atmel AVR Microcontroller on Linux

Easy to code for: AVRs were designed from the ground up to allow easy and efficient programming in high-level languages, with a particular focus on C.<p>…

Why is Donald Duck on the Radio? Math Behind Single Sideband Explained

AM, or amplitude modulation, was the earliest way of sending voice over radio waves. That makes sense because it is easy to modulate a signal and …

30 Handy Bash Shell Aliases For Linux / Unix / Mac OS X

An alias is nothing but shortcut to commands. The alias command allows user to launch any command or group of commands (including options and …

Linux

How to encrypt a USB flash drive with VeraCrypt

If you need to make use of encryption for a USB drive, there's no easier way than with the help of VeraCrypt. Jack Wallen shows you how.<p>Sometimes you …

How to Use Encryption: It's Easy

The past year was a tough one for data security, with consumers being affected by ransomware attacks, phishing scams, and a dizzying number of data …

EAGLE Tutorial: Library Part Creation Part 2 - Creating Symbols

1. Introduction<p>This is the second part of my EAGLE Tutorial series, following on from EAGLE Tutorial: Library Part Creation Part 1 - Creating …

Arduino

WebSockets

A WebSocket is a standard protocol for two-way data transfer between a client and server. The WebSockets protocol does not run over HTTP, instead it …

Learn C • Build Your Own Lisp

Build Your Own Lisp <br>Learn C and build your own programming language in 1000 lines of code!<p>If you're looking to learn C, or you've ever wondered how …

Fixing car using... Via https://twitter.com/ismonkeyuser/status/940486092041719808

An Introduction To Utilizing Public-Key Cryptography In Javascript

Open Cryptochat - A Tutorial<p>Cryptography is important. Without encryption, the internet as we know it would not be possible - data sent online would …

How we build real-time features using NodeJS and SocketIO

Users are increasingly enjoying instant access to information such as emails, messages in chat rooms, changes made by everyone for collaborative …

JavaScript

Build an Express API for Mongo database

I took a formal Mongo course by Stephen Grider on Udemy. I am very happy with the way Stephen teaches. It is slow. Very relevant and practical. I …

Putting the helmet on - Securing your Express app

Express is a great way to build a web server using Node.js. It’s easy to get started with and allows you to configure and extend it easily thanks to …

How To Make An HTTP Request in NodeJs? Http Mechanism & Libraries

Pick Javascript and master the art of both front-end and back-end development.<p>In our Node.js series of articles we have together covered till …