This unofficial site is devoted to the Raspberry Pi credit card sized computer offering tutorials, guides, resources,scripts and downloads. We hope to help everyone get the most out of their Pi by providing clear, simple articles on configuring, programming and operating it.
You will also find information about the BerryClip addon board, the easiest, cheapest way to start experimenting with hardware and software.
Posted in BerryClip
In my Introduction to the GertDuino I explained how it allows the Pi to compile and send code to an Atmega328 micro-controller. In this post I will explain the steps you need to take to get it up and running with an example program called “blink”.
The example is fairly basic and turns on the onboard blue LEDs. Once completed you will have a working system ready for your own experiments. When I started I had never used an Arduino so hopefully this post will help simplify some of things that confused me when I took the board out of the box.
I’ve just recently got hold of a new board by Gert van Loo, the volunteer engineer who helped design the Raspberry Pi. It’s the GertDuino and follows in the footsteps of the Gertboard.
The GertDuino is a an Arduino based add-on board for the Raspberry Pi. It offers the same features as an Arduino Uno but with some additional functionality. What is an Arduino you might be thinking? Well take a look at the Wikipedia page to find out. I’ve never used an Arduino so this seems like a good place to start. I will create blog posts as I learn and will try to present them in a way that they will be useful to someone else that has never used (or heard of) an Arduino.
Today I went to the DigiMakers (aka Raspberry Pi Boot Camp) event held in the @Bristol Science Centre. I had booked a place for my son on the “Controlling a Robotic Rover with Scratch” workshop run by Alan from Dawn Robotics.
The workshop was an hour and a half long and aimed to introduce using Scratch to control a Raspberry Pi powered vehicle. The vehicle had to move around its environment and locate an “artefact” which was in an unknown location. The rover had a camera and was capable of recognising black and white patterns using some basic computer vision.
If I need to edit text files directly on my Raspberry Pi my text editor of choice is nano. There are other text editors available but I prefer nano’s relatively straightforward interface.
As a command line based utility it may feel strange for users who are more familiar with a graphical interface but it is easy to learn the basics. Syntax colouring is available which makes reading and reviewing scripts easy.
As soon as I ordered some Pi NoIR camera modules I also ordered some bits and pieces for testing. This included some standard IR LEDs and a couple of cheap IR CCTV illuminators.
These would allow me to test with the camera module and work out what sort of IR lighting I needed for different applications. Ideally I was looking for suitable lighting for an outdoor security camera and I wanted to workout if it would be easier to use ready made lights or make my own.
The Raspberry Pi camera has been available for a while now and it has resulted in plenty of camera based projects.
Like many camera modules it is fitted with an infrared (IR) filter which is there to improve overall image quality. Humans can’t see infrared so it most cases it is better to filter it out and tune the camera to visible light. Most webcams use a similar technique.
However this reduces the usefulness of the camera module in some applications. Many webcams can have the filter removed with a bit of hacking but this wasn’t very easy with the Pi camera … until now.
The Raspberry Pi has no built in analogue inputs which means it is a bit of a pain to use many of the available sensors. I wanted to update my garage security system with the ability to use more sensors so I decided to investigate an easy and cheap way to do it. The MCP3008 was the answer.
The MCP3008 is a 10bit 8-channel Analogue-to-digital converter (ADC). It is cheap, easy to connect and doesn’t require any additional components. It uses the SPI bus protocol which is supported by the Pi’s GPIO header.
This article explains how to use an MCP3008 device to provide 8 analogue inputs which you can use with a range of sensors. In the example circuit below I use my MCP3008 to read a temperature and light sensor.
“Adventures in Raspberry Pi” is a book by Carrie Anne Philbin, a valued member of the Raspberry Pi community.
Miss Philbin is a secondary school teacher of computing so knows a thing or two about the challenges of teaching kids computer programming. Her book aims to teach computer programming and some system administration skills to kids using the Pi. No previous knowledge is assumed so is suitable for everyone.
The book is written with 11-15 year olds in mind but I suspect it will be useful for a younger audience with appropriate support.
Posted in Books, Programming
It’s that time of year when mad inventors start creating Halloween themed electronics projects. I’ve never managed to be organised to do a seasonal project but this year I decided to give it a try.
So this year I decided to take what I’ve learnt about the Pi-Lite and create a simple Halloween project I can stick in the window along side our more traditional carved pumpkins.
In my previous post about the Pi-Lite I explained how to set it up and how you could display scrolling text in Python. In this post I will explain how to create custom 14×9 pictures and then send them to the Pi-Lite. This is the same technique used to create the Pac Man image to the right.
The Pi-Lite has a frame buffer feature which allows you to send it data which determines the state of each LED. You can set each LED to be on or off and once all your data has been received the Pi-Lite sets the LEDs as instructed.
This command is a string of 126 ones and zeros. The string defines the top left LED and then works down the first column. It then defines the second and so on until all 126 LEDs have been set to either a 1 or 0.