I’ve recently got myself an Amazon Echo Dot; Amazon’s speech-based, voice-controlled device using Amazon’s Alexa, digital assistant. They’re pretty nice devices; and they’re quite fun to play with (and not too expensive either) – though I’ve not had it long enough to say if it’s actually useful yet… Obviously the first thing that I did with […]
Last time we looked at how to write a server application in C++, and call it from Python. This time, we’ll do things the other way around: implementing a service in Python, and calling from C++.
Inspired by the famous XKCD cartoon that started it and by Google’s Peter Norvig over on O’Reilly.com I decided to play some RegEx Golf myself this Easter… If you’re not familiar with the game – the idea is to write the shortest regular expression possible that will select every element of a list, without selecting […]
Xbee modules provide a very simple way to add a wireless capability to communications on Arduino. Essentially they let you work in exactly the same way as a direct serial connection between two boards – albeit wirelessly. The easiest way to connect an Xbee to your Arduino, is to use the Arduino Wireless Shield. It’s […]
In my last post on using sysfs for GPIO on Raspberry Pi, I showed you how you can use the sysfs file system to manipulate the state of the GPIO pins. This time, we’re going to explore how to do the same thing programmatically. I’m going to walk you through developing a C library to […]
EDIT (August 2023) – The technique outlined here will still work, but it’s been deprecated for some time now – so I’ve written a new post about how to use the new methods… The Raspberry Pi (in case you’ve been living under a rock for the last six-months) is a cheap ($25) ARM Linux computer, primarily […]
Here’s a video that I made, talking about one way to use seven-segment displays with a microcontroller.
In my previous posts in this series I looked at a couple of ways to use an Arduino to generate analogue waveforms. In this third part I look at a much simpler, IC-based digital to analog (DAC) circuit to provide the waveforms, and look at ways of changing the frequency of the output.