During my time with the Pi I’ve experimented with various devices and sensors. Here is my Top 10 list of devices to connect to the Raspberry Pi. In most cases they are very cheap and easy to interface and are great building blocks for more complicated future projects. I’ve included links to more detailed posts where I can and many of these include example Python scripts to help you get going. From robot cars to security systems there are plenty of ways of combining these mini-projects into some amazing creations! If you need to buy a present for a Pi…
Author: Matt
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While searching for a simple way to measure temperature using my Raspberry Pi I came across the DS18B20 1-wire digital temperature sensor. This promised an accurate way of measuring temperature with a few wires and almost no external components. The device only cost a few pounds and it seemed too good to be true …
Following on from my first PIR sensor module article I thought I would create a Python script that allowed me to easily measure the reset time. That way I could attach a module, run the script and measure the time it took for the output pin to drop back to the Low state. Then I could tweak the trimming resistor and adjust the reset time to my preferred value in a more controlled and precise way.
Interfacing a Raspberry Pi with a Radio Controlled car was on my list of projects so I need to experiment with powering the Pi from batteries. I had a number of basic requirements. Use AA batteries as I already had lots of rechargeables and chargers Reduce the overall cost low by keeping additional electronics to a minimum The batteries would be required to power the Pi which needed 5V. AA batteries can vary in voltage from 1.2V-1.5V so some sort of voltage regulator was required to provide a stable 5V to the Pi. With the addition of a Bluetooth or…
All Raspberry Pi boards have at least one status LED. The number and position of these varies between the different models. Below is a list of the different configurations you are likely to find on your Raspberry Pis.
From the very beginning the Raspberry Pi Foundation aimed to create a device that would encourage young people to experiment with computers, programming and real-world hardware. Just as George Lucas decided to make Star Wars Episode 4 first, the Foundation released the Model B as it had the best chance of catching people’s imagination. It succeeded. Now it is time for the Model A to make an appearance on the Raspberry Pi stage. The Model A is almost identical in both specification and appearance to the Model B but with the following main differences : It has no Ethernet port…
I was looking for a way to send data to my Raspberry Pi via Bluetooth. Ideally I wanted to do this via an Android tablet and a custom app but I couldn’t get the app to connect. During a large amount of Google searching I came across a Python library called “CWiid”. It allows you to read data from a Nintendo Wii Controller via Bluetooth and use this within your own Python script. So I decided to give it a go and see how easy it was. As it turned out it is not difficult at all once you know…
Following on from my Ultrasonic Distance Measurement Using Python – Part 1 article I decided to make my Python script a little bit more sophisticated. In this example the script takes three measurements and calculates the average. This is displayed and one second later it takes another average. This allows the script to be used to constantly measure distances and print them to the command line.
The Gertboard is an add-on board designed by Gert van Loo who is also one of the hardware engineers involved in the original design of the Raspberry Pi. The board was originally sold by Farnell/Element14 in kit form but has just been re-launched as a fully assembled unit. This may come as a disappoint to those people that wanted to solder their own boards but perhaps a relief to those that will be happy with a pre-built product. The Gertboard plugs directly onto the Raspberry Pi GPIO header and provides a range of features and interfacing possibilities including : Drive…
A great little sensor you can add to your Raspberry Pi projects is a PIR module. These 5V “Passive Infra Red” sensors are available for a few pounds from eBay. They can be powered from 5V and output 3V so can be connected directly to pins on the Pi’s GPIO header without any other components. The module sets a single output pin high whenever it detects movement within its field of view. It holds this pin High (3.3V) for a minimum period of time. If continuous movement is detected the output pin will stay High. When the time has elapsed…
This is a list of the free tools and utilities I use on a regular basis when messing around with Raspberry Pi development. They are quite specific to the type of projects I am working on but I thought people might be interested in what is available. I would have liked this to be a “Top 10” but I only wanted to include applications I genuinely used on a regular basis. So there was no option but to make a “Top 8”! All the tools listed are free to use but in some cases only for non-commercial use.
It’s possible to buy preloaded SD cards to use with your Raspberry Pi but at some point you will need to learn to create your own. This will allow to update your system for free or allow you to create multiple SD cards, perhaps one per project. In this article I will explain how to write the latest official Raspbian image to an SD card using the free Fedora ARM Installer utility. Apart from a few minutes of your time this process is completely free. [UPDATE Nov 2016 : The Fedora ARM Installer is no longer available on Windows. I…
Ignoring the fact that they made the mistake of turning a two film story into three films, The Matrix is cool. Regardless of what my wife says. So I decided it was vital that I get the Matrix text “rain” on my little 12V LCD screen. A quick Google and I found ‘CMatrix’ written by Chris Allegretta. This can be easily installed on the Pi using apt-get. I’m using the standard Raspbian image but I guess it will work for other distributions.
LEDs, buzzers and switches are the most common items people attempt to interface to their Raspberry Pi’s. Something I found in eBay that is a little bit different is an ultrasonic measurement module. This allows you to measure the distance to the nearest wall or solid object. The modules are easy to buy, cheap and relatively straight forward to interface to the GPIO header. So here is some information on my experiments with an Ultrasonic measurement module and Python. In future projects I can see these modules being a great way to add some intelligence to a Pi powered robot…
Lots of people experimenting with the Raspberry Pi already have a box full of tools suitable for electronic hardware projects. However if you are just starting out you may be wondering what you need to get up and running. This article aims to list the things you might want to consider buying. You don’t need all of it and it depends on your project but the items below have all proved useful to me. You do not need to spend a fortune. Better quality tools cost more but sometimes the extra cost simply isn’t worth it. The only thing in…
Most of the later Raspberry Pi models have mounting holes. These give users some extra options when it comes to mounting the Pi and depending on the design the Pi will have either two or four holes. I have created a Raspberry Pi mounting hole template that can be printed onto paper and used to drill holes in cases or other materials for attaching a Pi to. It also includes the Pi camera module which has four mounting holes. This template is the quickest and easiest way to put holes in the right place, first time.
The Raspbian SD image gives your Raspberry Pi a default name of ‘raspberrypi’. This name appears in the command prompt. Many people will leave it at the default but you may wish to change it to something more unique. It’s quick and easy to change by following the steps below.
At the Bristol Raspberry Jam in October 2012 I saw someone with a small 3.5 inch LCD attached to their Raspberry Pi. It cost less than £20 so I decided to buy myself one. I had no idea what I was going to use it for but decided to worry about that another time. What you get in the box 3.5 inch TFT LCD screen 2 female phono sockets for AV inputs (Yellow & White) 1 male 5.5mm DC power jack with in-line fuse (Red) 1 cable with female 5.5mm DC power plug on one end (Black)
The default Raspbian SD card image configures a default user account called ‘pi’ with a password of ‘raspberry’. Every device using this image will therefore have the same username and password combination. This is great for quickly getting starting but isn’t very good practice from a security point of view. You should therefore consider changing the default password as soon as possible. It’s easy to do and only takes a minute. There are three methods you can use : Method 1 – Change Raspberry Pi Password on the Command-line From a command line prompt type passwd followed by the Enter…
On 15th October Bristol held its second Raspberry Pi Jam at the Bristol & Bath Science Park. The event was attended by over 100 people and included some weird and wonderful project demonstrations. The plans were disrupted with the almost unavoidable problems with projectors and HDMI connections but three projects were presented.
The Raspberry Pi Revision 2.0 introduced a new header to the PCB. This header is called P5 and consists of 8 pins. It is located directly underneath the standard 26 way P1 GPIO header. It was intended that this header is populated on the underside of the PCB so any connectors or cables do not interfere with the P1 header. Pin 1 has a square pad whereas the other 7 have circular pads. The P5 pins provide : +5V, 3V3 and Ground GPIO28 GPIO29 GPIO30 GPIO31
My Raspberry Pi Revision 2.0 arrived from Farnell today. I almost fainted when I saw the word “China” on the label but luckily the white box contained a Revision 2.0 board stamped “Made in the UK”. This means it was made a the Sony factory in sunny Wales. This meant I could marvel at the new mounting holes, the blue audio jack and the new mysterious P5 header. So here are a set of photos I have just taken so you can compare to the Revision 1.0 Pi :