Monthly Archives: April 2013

Driving LED Arrays

I have started to investigate how I can drive a large bank of LEDs directly from my Beaglebone or Raspberry PI. I have developed a video before:

where I drove a 2 colour 8×8 LED common anode dot matrix display using three 74HC595s and a transistor array UDN2981A to source the current. This used the Arduino as the platform to drive […]

By |April 28th, 2013|Beaglebone, Digital Electronics, Raspberry PI|3 Comments

Remove index.php from your WordPress URL

You will notice that this site which runs using WordPress that there is no index.php in the URL when you are directly addressing a page/post or when you are linking to other pages/posts. This can achieved using the following configuration.
There are two step 1’s, depending on whether you/your web provider is using Apache or Zeus scripting. To […]

By |April 27th, 2013|Blog|22 Comments

Building Ångström for Beaglebone from Source

The Ångström distribution is a Linux distribution for many embedded devices, the Beaglebone included. Here I am going to document the steps that I took in order to build a full distribution of Angstrom (easier to write without the unusual letters). I am working from the steps described at this site: but here I will document any difficulties and the times […]

By |April 23rd, 2013|Beaglebone, Blog|36 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

Linux Portscan Your Network

It can often be the case that you need to scan the network to find a particular machine that has received a different IP address under a DHCP (Dynamic Host Configuration Protocol) allocation.

The easiest way to do this under Linux is to use:

Where I am scanning in the range of DHCP allocation that I have allocated on my network. My […]

By |April 20th, 2013|Blog, General, Linux|0 Comments

Beaglebone: Embedded Linux and Stepper Motors

This video examines how we can drive stepper motors using C++ within Embedded Linux using the open source hardware EasyDriver board. The video begins by describing stepper motors and the effects of micro-stepping. It then discusses the EasyDriver Board (V4.4) and all of the available inputs and outputs. The board uses the Allegro A3967 which allows for full, half-, quarter […]

By |April 16th, 2013|Beaglebone|15 Comments

Building FFMPEG for Beaglebone from Source

For my USB Logitech C920 MPEG4 webcam I decided that I would try to build ffmpeg from source and see if it improved the streaming capability of the camera. Currently, the stream is halting after about 30 seconds and the data stream becomes frozen.

So, based on the steps at this link I downloaded the x264 source and built it. I had […]

By |April 15th, 2013|Beaglebone, Blog|9 Comments