Writing a Linux Kernel Module — Part 3: Buttons and LEDs

Introduction
In this series of articles I describe how you can write a Linux loadable kernel module (LKM) for an embedded Linux device. This is the third article in the series — please read:

Writing a Linux Kernel Module — Part 1: Introduction, and
Writing a Linux Kernel Module — Part 2: A Character Device,

before moving on to this article, as those articles […]

By |April 26th, 2015|Beaglebone, Blog, Linux|40 Comments

Writing a Linux Kernel Module — Part 2: A Character Device

Introduction
In this series of articles I describe how you can write a Linux loadable kernel module (LKM) for an embedded Linux device. This is the second article in the series — please read “Writing a Linux Kernel Module — Part 1: Introduction” before moving on to this article, as it explains how to build, load and unload loadable kernel modules […]

By |April 18th, 2015|Beaglebone, Blog, Linux|20 Comments

Writing a Linux Kernel Module — Part 1: Introduction

Introduction
In this series of articles I describe how you can write a Linux kernel module for an embedded Linux device. I begin with a straightforward “Hello World!” loadable kernel module (LKM) and work towards developing a module that can control GPIOs on an embedded Linux device (such as the BeagleBone) through the use of IRQs. I will add further follow-up […]

By |April 14th, 2015|Beaglebone, Blog, Linux|28 Comments

Introduction to CMake by Example

Introduction
This article provides a straightforward set of “Hello World!” introductions to using CMake for building C++ projects. All steps are performed using Linux on the BeagleBone platform, but the instructions are relevant to most Linux platforms.
The make utility and Makefiles provide a build system that can be used to manage the compilation and re-compilation of programs that are written in any programming […]

By |April 1st, 2015|Beaglebone, General, Linux|26 Comments

CGI using C++ on the BeagleBone (Ggicc)

Introduction
In Chapter 10 of my book (pg. 388-393), Exploring BeagleBone, I describe how you can build web-based CGI applications that can interface with electronics hardware that is attached to the BeagleBone using Bash scripts that call C/C++ programs. The solution works well for very straightforward applications, but this discussion investigates more advanced solutions for applications where there are more complex interactions — for example, […]

By |March 27th, 2015|Beaglebone, Embedded Systems, Linux, Raspberry PI|3 Comments

Exploring BeagleBone: Tools and Techniques for Building with Embedded Linux

This is what is keeping me busy at the moment… (very, very busy!). I have presently drafted 9 of the 14 chapters. This book on the BeagleBone is due for publication in Dec. 2014. A provisional description is available at: http://www.amazon.com/Exploring-BeagleBone-Techniques-Building-Embedded/dp/1118935128/
There is a website to support this book at: www.exploringbeaglebone.com
Derek.

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[This is a draft description, please see the website for the final description […]

By |June 18th, 2014|Beaglebone, Blog, General, Main Blog|60 Comments

Analog Discovery: Getting Started with the Analog and Digital Tools

Introduction
I recently purchased the Digilent Analog Discovery and this is my first post on the tools that are available. I wrote this as a set of blog posts, but I have now replaced this with a full video on my YouTube channel

In this video I investigate the use of the Digilent Analog Discovery with Waveforms and look how it can […]

By |January 12th, 2014|Analog, Blog, Digital Electronics, Main Blog, Tools|0 Comments

Analog Discovery: Getting Started with the Logic Analyzer and Digital Pattern Generator

Introduction
I recently purchased the Digilent Analog Discovery (Revision C). In this post I am looking at the Digital features, in particular the Pattern Generator and Logic Analyzer functionality.
Test Circuit Setup
For this test circuit I am going to use a JK Flip-Flop, in this case a negative-edge triggered JK Flip-Flop, the 74HCT112N, which is manufactured by NXP/Philips. Like all JK Flip-Flops, it […]

By |January 12th, 2014|Blog, Digital Electronics, Tools|0 Comments

DIY LED Aquarium Lights Tutorial

In this post I give a short video tutorial on how I built the LED fish tank lights for my fish tank. I’m using high-performance Cree XP-G LEDs (XPGWHT-R5) on 23mm star PCBs. Each one outputs 556 lumen at 350mA. I use 6 in this video to give an output of 3,336 lumen at a cost of about 39 Watts […]

By |June 22nd, 2013|Blog, General|13 Comments

Resize a VirtualBox guest Linux VDI Disk under Windows Host

My Linux VirtualBox guest OS often runs out of space – I never learn that to build anything in Linux, you need about 10 times the amount of space that you think you need. Also, VirtualBox recommends very small default values, so it is easy to be caught out.

Anyway, here are the current steps to re-size a VirtualBox disk, where Linux is the […]

By |April 21st, 2013|Blog, General, Linux|158 Comments