Author Archive | Daniel

Getting Started: Using Sparkles

The Sparkle has got to be one of the most popular and satisfying Crumbs (components) for the Crumble. It is an easy to use RGB LED, which can be set to pretty much any colour. If this wasn’t enough, you can chain up to 32 together, and individually control each one!

They’re really easy to get started with, and are often used as a starting point, due to the clear results and feedback. We’re going to focus on connecting individual Sparkles, however we will look at other Sparkle-based items later on.

To get started, you will need to connect your battery pack to the Crumble. Notice that we connect the positive (+) on the battery pack to the + on the Crumble, and the negative (-) on the battery pack to the – on the Crumble.

Hint: You can connect to either the left or right + and -, but we use the left as standard.

Now we need to connect up our Sparkle. It’s important to get this bit correct, otherwise they won’t work. We need to connect the + and – from the Crumble to the corresponding connections on the Sparkle, and D, which you can think of as ‘data’ connects to the D input on the Sparkle. Take care to notice which way the arrow on the Sparkle points (away from the Crumble).

Now it’s time to get programming! Connect the Crumble to your computer via the micro USB lead, and open up the software. Write the following code, and think about what it will do before you run it. If you need more help programming, check out our first ‘Getting Started’ blog.

When you’re ready, switch on the batteries and run the program. You should see that your Sparkle has now turned red.

Changing the colour of your Sparkle is really simple. Click on the box with the colour in to bring up a colour palette, and select your colour of choice. Reprogram your Crumble and watch the colour change!

More Sparkles

Using multiple Sparkles is just as easy as using one! First of all, let’s connect another one to our chain. We connect the second Sparkle to the right hand side of the first one, matching the +, – and D connections. Notice the direction of the D arrow – it still points away from the Crumble.

Controlling each Sparkle individually is also really simple, in fact if you’ve followed these instructions, you’ve already done this. The number at the beginning of the Sparkle block, 0 by default, represents which Sparkle we want to control. This means that the 2nd Sparkle is ‘1’ and the 3rd would be ‘2’ etc. If you want to change which one you’re controlling, click the white box and change the number – you can control up to 32 of them.

If you want to set all of the Sparkles you’ve got connected to a single colour, you can use the ‘set all sparkles’ block. This sends the information to turn all of the Sparkles to the chosen colour.

Turning them off

It’s all well and good being able to change the colour of a Sparkle, but what if we want to turn them off instead? This is as easy, if not easier than changing their colour.

We can use either of the blocks pictured above, either to individually control one to turn off, or to turn them all off.

There is also another way to turn Sparkles off. You may have noticed already that the colour picker includes black, and for those of you that didn’t know already, we cannot shine a light black. In fact it is the opposite, it is an absence of light. Therefore if we set our Sparkle to be black, it will turn off!

Using RGB Values

The final two blocks that we haven’t covered (for individual Sparkles) are the RGB blocks. These blocks work in exactly the same way as the others, except we don’t use a colour picker to assign the colours, we instead choose how strong we want the red, green and blue emitters to be.

To change the values, click on the number within the red, green or blue boxes – you can insert a value between 0 and 255, 0 being low or off, and 255 being high, or fully on. You can also put variables in here too.

To help visualise the effect of changing the values, take a look at this graphic. The red, green and blue line represent the how strong we want the corresponding colour, between 0-255, and the background colour represents the colour that the Sparkle will produce.

Once you’re comfortable with how to connect and code Sparkles, you can include them in all manner of projects! Remember how we said that you can connect and control up to 32 at once? Well instead of wiring them up individually, we also do a Sparkle Baton (8 Sparkles), a Sparkle Matrix (5×5 grid of Sparkles), and a flexible Sparkle strip (30 Sparkles) all for your shiny pleasure, because let’s face it – you can never have too many lights!

We hope that this has covered the basics of how to use Sparkles, but if you do have any queries or questions, or you spot something that isn’t quite right feel free to get in touch! Get in contact with us via emailFacebookTwitter or our Forum, and we may feature your work!

Getting Started: Flashing the Motor LEDs

One of the very first things you can do when you get started with a Crumble, is to flash the Motor LEDs. This is pretty much the ‘Hello, World!’ program within the Crumble ecosphere.

It’s really easy to do, and it doesn’t require anything other than a Crumble, micro USB lead and a computer with the software installed.

So to get started, connect the USB lead into your computer, and connect that to the Crumble.

Now, if you haven’t already done so, open up the Crumble software. To get a motor LED on, we’re going to run the following program. Drag the blocks from the toolbar, connect them together, and hit play when you’re ready.

All being well, you should see a message telling you that programming was successful. Take a look at your Crumble – you should see that the motor LED is now on. Well done for writing your first Crumble program!

Now let’s move onto flashing the motor LED. As before, drag your blocks over and have a go at writing the following program. Before you run it, think about what it might do.

Hint: You can change/edit parts of blocks that are white or grey – click on the word ‘forwards’ to cycle through to stop.

Hopefully your motor LED is now flashing away. If you want to make the other side flash, simply click on the ‘1’ in the motor block, and it will change to 2!

Programming the Crumble is as easy as that! When you feel comfortable, you can move onto connecting the battery pack along with other components, like Sparkles, switches buzzers etc. If you want any ideas or inspiration for what to make, check out our blog or project pages.

Scanner Bot – The Inside Scoop

For those of you that ventured along to Bett this year, you may have spotted a small spinning robot on our stand, which we christened ‘The Scanner Bot’.

You may have even seen posts about it on Twitter. The project drew a lot of attention, and eventually it got us thinking – we need to turn this into a project on the website.

The idea for the project actually stemmed from last year’s Bett, where Helen, one of the Directors here at Redfern, wanted to highlight that fact that motors can be used in different ways. So whilst we were there, she created this :

As you can also see, Helen had been inspired by the video of a students’ work, posted by Phil Wickins.

Given that the inspiration for our new Scanner Bot had been ‘magpied’, we wanted to give credit where credit is due. So we contacted Phil to tell him about our project idea, and whether he was ok with us referring to it.

When he came back to us, he had gone above and beyond in providing loads of information about the project, including the original design work, which is awesome!

Meet the ‘Burglar Alarm Bot’ – the true inspiration behind our Scanner Bot project.

The Burglar Alarm Bot was made by William Bradley, a Year 6 pupil from Bitterne Manor Primary School, Southampton. We absolutely love this project, and as you can see, it looks great and it works really well!

In his blog about the teaching that went around this project, Phil outlines his creative approach to teaching physical computing. Instead of having a set project in mind, he teaches the children how to use the individual components, and then lets them use their imagination to come up with a project. We really like this approach to physical computing, as it enables children to work within their means, and push themselves to their own limits. The phrase “low floor, high ceiling and wide walls” comes to mind here.

One of the most important steps within this process, is the planning stage. As you can see from William’s design, he was confident in how he wanted his project to look.

The careful thought and consideration that went into the planning stage, and the prior learning (components) meant that William knew how the ‘insides’ would fit together, and this lead to a brilliant project.

Although we’ve focussed primarily on the Burglar Alarm Bot, if you head over to Phil’s blog, you will see many more great designs by the other pupils in his class.

If you want to have a go at making your own Scanner Bot, head over to our project page.

If you have a go at this project, or any other, we’d love to see! Get in contact with us via emailFacebookTwitter or our Forum, and we may feature your work!

I have the NEW Starter Kit – What Next?

The eagle-eyed amongst you, along with any one who saw us at Bett, or anyone that has ordered one already, will have noticed that the Starter Kit has changed!

Our New Starter Kit

It’s a long-discussed decision, and we finally felt that now was the right time to do it. Since its inception, the Starter Kit has undergone a few changes, including swapping out a normal battery box, for our short-protected one, and more recently, switching the plain white box for a fancy printed version, all whilst keeping the price the same!

The Starter Kit remains a very popular way for schools to get their hands on Crumble kit, with many opting to buy 15/16 for a class of 30 pupils. Although there are a good number of projects you can do with it, we decided that we wanted even more.

We thought long and hard, and we’ve now added in a buzzer and a light sensor, which transforms the number of projects you can do with just the starter kit!

Without further ado, let’s get stuck into some project ideas!

First of all, if you haven’t already looked at it, make sure to check out our original post. All of the projects still apply, but they don’t make use of the buzzer or the light sensor.

Morse Code

For a start, let’s look at morse code. We covered this in our original post, however morse code is traditionally audible – therefore it makes sense to put the buzzer to use!

The buzzer can be wired/controlled in a few different ways. You can either connect the positive side to an output (A, B, C or D) and the other end to negative (-) on the Crumble or the battery back, or you can connect the + and – to the corresponding connections on a motor output. We’re opting for the former.

To demonstrate it, we’ve opted to make the letter C. To sound the buzzer, set the output it is connected to, to HI. To stop the buzzer sounding, set it to LO.


Next up, we have a simple night light. The idea behind this is to create a light, using the Sparkle, which turns on when it gets dark. Connecting the light sensor is easy. Connect the + on the light sensor to a + output from either the Crumble or the battery pack. Then connect the negative (-) on the sensor to an I/O (A, B, C or D).

To incorporate this into a program is simple. We can either take and use the analogue reading from the connected I/O pad, or check whether the pin is HI or LO. We have used the latter for simplicity (this wouldn’t be easy with the old LDR). If A is HI, it is therefore light so we want to turn the Sparkle off, otherwise A must be LO, and it is dark so we want to turn the Sparkle orange.

If you want more detail, head to our nightlight project page.


Extending the idea of a nightlight brings us neatly onto a lighthouse. By using the same components, we can achieve a different outcome.

We’ve chosen to write the code slightly differently, to show how there are multiple ways of achieving the same outcome. This time our condition checks whether or not A is LO (it is dark). If it is, flash the Sparkle. Otherwise, turn the Sparkle off.

If you want more detail, head to our Lighthouse project page.

Drink Alarm

Our final idea combines the principles of the previous projects together, as well as the buzzer and light sensor. The idea behind this is that you have an object e.g. a drink on top of the light sensor. When the item is removed, the buzzer sounds. You could even add a flashing light if you wanted too!

Once again we’ve chosen a ‘different’ way of programming this. You could easily use the ‘IF__ELSE’ condition from the previous examples. This time we are putting a ‘pause’ on our program which waits until A is HI (the drink is removed and it gets light). After this condition is met, the program continues and beeps the buzzer. We then loop back to the beginning. If A is still HI then we keep hearing the buzzer beep.

These are just a few more examples of projects you can do with the Starter Kit, and we are sure that you will think of many more!

If you have a go at this project, or any other, we’d love to see! Get in contact with us via emailFacebookTwitter or our Forum, and we may feature your work!

Crumble Heads to Bett

Once again, some of the team here at Redfern are going along to exhibit at Bett – the British Educational Training and Technology show. The show takes place at the ExCel centre in London, and is one of, if not the largest educational technology shows in the World.

Last year’s stand at Bett.

Boasting over 34,000 attendees from 131 Countries spread across 4 days, Bett is no small feat. This year, the show is running in a slightly different way. Last year saw The Education Show take place alsongside Bett, but this year it will be ‘inside’ of it. Additionally, the show will be separated into six different zones: Learning Tech, Teaching Tech, Management Solutions, The Education Show, Equipment and Hardware, and Global Showcase. We will be in the Learning Tech Zone.

We will be there showcasing the Crumble, as well as telling you all about some new accessories and software upgrades we have in store! We will also have various items for sale at a discounted rate!

Bett is free to attend and it runs from 22nd – 25th January. Why not pop along and see us on stand SD70.


Jazz up your Christmas Tree

Christmas is fast approaching, and to spruce up the office we decided to get a tree. However, this tree is a little bit different. Are they massive flexible Sparkles or is the tree really small?

Sadly, it is the latter. We picked up the tiniest little Christmas tree, and decided it needed a bit of a Crumble makeover. 

We snipped 10 lights off of our Flexible Sparkle Strip and soldered them together. If you don’t feel confident enough doing this, you could use the whole flexible strip and wrap that around your tree, or if you want to use big Sparkles, you can croc-clip them together like we did a couple of years ago.

After decorating, you can then program your own custom light sequences! We decided that we wanted a fairly classic light sequence, lighting up random colours between red, orange, yellow, green and blue. To achieve this, we are taking inspiration from our ‘Random Colour Picker’ blog

The program is simpler than it looks. Assign a variable a number, which will define what colour our Sparkle will light up. Then set a random Sparkle between 0 and 9, to the chosen colour. Wait 10ms before doing it all again!

This is not only way way of running your lights – you could have them fading through RGB, pulsing on and off, chasing up and down the tree, or you could even make your tree interactive!

Our lovely bit of festive cheer, to brighten up the office.

Thank you all for making this our best year yet. We have many exciting things planned for next year, and we are excited to share them with you soon. We hope you all have a wonderful Christmas, and a Happy New Year! See you in 2020.

If you have a go at this project, or any other, we’d love to see! Get in contact with us via emailFacebookTwitter or our Forum, and we may feature your work!

DIY Switches 2:

One blog post was definitely not enough to look at DIY switches. Given how simple the idea is, it’s surprising just how many different ways you can make a switch! If you haven’t already seen it, take a look at our first post.

We love these, as they provide an alternative way of using interesting inputs with the Crumble. We’ve decided to show you a few more examples of switches you can make yourself, and whilst going through this process we’ve thought of a brilliant idea for a new project, which we are working on now.

The first switch we have here, is a moisture sensor. It is made using two strips of copper tape (you could use anything conductive) placed close together.

If you wet your finger and place it across the two strips, the moisture bridges the two pads, causing the switch to be ‘closed’.

Next up, we have a reed style switch. For those of you unfamiliar with a reed switch, take a look at our Magic Candle blog to see it in action. Put simply, it’s a switch that is triggered (closed) by a magnet. We have fashioned our own using some aluminium foil (not magnetic), and a nut glued to the raised flap of foil.

When a magnet goes near the underside of the switch, the nut is pulled towards the other piece of foil, closing the connection. When the magnet is moved away again, the foil flaps open again. It’s amazing how resilient and springy foil can be!

Now we move onto something a little bit different. We’re going to call this a ‘joust switch’. It serves the same purpose as a whisker/bump/micro switch.

When it is pressed, the connection is broken (push-to-break). We can use this as a limit switch, and easily make a bump-and-reverse buggy!

Our final switch takes inspiration from a tilt switch. We have left the top off of this version, to make it easier to see what is going on.

When tilted in a certain direction, the ball bearing touches our two electrodes, closing the switch. When it’s tilted back, the ball bearing moves away from the electrodes and breaks the connection, opening the switch.

And there you have it, more switches to use with your projects!

If you have a go at this project, or any other, we’d love to see! Get in contact with us via emailFacebookTwitter or our Forum, and we may feature your work!

DIY Switches

Although the outputs (motors, Sparkles, buzzers etc) of the Crumble get a lot of love and attention, we mustn’t forget how awesome inputs are! They allow us to interact with our projects. Arguably the simplest type of input, the humble switch provides us with a digital(binary) input for the Crumble; it is either on/off or HI/LO.

Before we look at making our own switch, we need to consider what a switch is, and what it does. This will help us later on. If you already have a good understanding, then feel free to skip over the next bit.

First, let us consider a circuit – a closed loop of conductive material and electronic components through which electricity flows. The important word here is ‘closed’. Electricity will only flow when there is a clear path from positive (+ve) to negative (-ve). If we break the circuit/connection, then the electricity will stop flowing. This can be very useful when we want to control components in a circuit e.g. a buzzer or a light. We can do this by using a switch – a component which we use to control the flow of electricity.

There are all manner of switches available, from a good ol’ push switch to an illuminated key switch. But sometimes there just isn’t quite the one we want, or one we can integrate into a project how we want. A great way of solving a particular problem and thinking about how switches work is to make your own. To make something, which when interacted with in some way, will close a circuit. Not only does this give you a great insight as to how switches work, the concepts involved are perfect for meeting various Computing/Science/Design & Technology curriculum targets.

So without further ado, let us look at different ways to make switches!

First of all, let’s make a classic split pin/paperclip switch.

By moving the paperclip, we can open/close the switch. The paperclip joins together our two contacts (split pins), which are connected to the Crumble – one on a +ve output, and the other to an input (A, B or C – D is used for a Sparkle). When the connection is made, A becomes HI and the Crumble turns a Sparkle on red. When the connection is broken, the Sparkle turns off.

Our code for this is as follows. Although not the most efficient way of achieving our desired result, this code is easily extendable for our rotary switch. If A is HI, then set the Sparkle red, otherwise turn the sparkle off.

Continuing along the theme of a simple switch, lets make a ‘pressure pad’ style switch.

When pressure is applied to the top surface, the foil bridges the gap between the two foil contacts on the bottom surface (connected to the Crumble as before). This then runs the same program as before – the switch is a straight swap.

Finally, we decided that we wanted a rotary switch, with multiple outputs.

The centre arrow can be lined up with one of three outputs. Each one connects to a separate input on the Crumble. Depending on which one of the inputs is HI, the Crumble lights the Sparkle red, green or blue.

The code for this is an extension of our previous two switches, except that we check for multiple different conditions being true (inputs being HI).

These are just a few different ways of making your own switch. By taking the very basic principle of ‘bridging a gap’ and closing a circuit, you can easily let your creativity run.

If you have a go at this project, or any other, we’d love to see! Get in contact with us via emailFacebookTwitter or our Forum, and we may feature your work!

The Crumble at New Scientist Live

Last week saw us attend what is coined as ‘the world’s greatest science festival’. Over 40000 people attended across the four days, and made, what turned out to be an amazing show.

We had never been to, let alone exhibited at New Scientist Live (NSL) and as such, we were not sure how successful or useful the show would be. We’d ended up being at the show, after it was suggested to us that the Global STEM Award and the Crumble would fit in well. So we thought about it, and gave it a shot.

We ended up having a fantastic time, not just looking around the show, but talking to, and interacting with so many wonderful people! It’s lovely to watch children and adults alike being enticed in by a plethora of exciting Crumble activities.

UKSTEM were on the stand with us, talking about the Global STEM Award, and showing off their latest developments (which will be announced soon). For the vast majority of the show, we were swamped with people!

Mike from UKSTEM talking about the Global STEM Award

For the Crumble parts of the stand, we decided to work on making it look more exciting and fun to use. As we were in the lunar section, we went with a ‘spacey’ theme. We had two main Crumble activities – the first was to pre-program a lunar vehicle to get from one area of ‘the Moon’ – to another.

A Crumble Buildbot on our lunar surface

And the other was to recreate a light signal, which was shown to you on a matrix display. After programming a Crumble, you ‘docked’ it onto the giant matrix display to see if you had gotten the pattern correct!

Our giant Crumble Matrix

All in all, we had a brilliant time over the four days. We had many interesting conversations with people about the Crumble, our mini dataloggers and the Global STEM Award. and I definitely think that we will be exhibiting next year.

NCW Day 5 – Game Time!

Welcome to our fifth and final blogpost from our National Coding Week special. If you’ve missed any of the other four, or want to find our more about what we’re doing, and why we’re doing it, then head over here to find out more.

This final post, as mentioned previously, is all about playing a game. We are going to combine together each of our previous elements, and turn them into something playable! To recap, we’ve got the Colour Picker, the Dice, the Letter Spinner and the Countdown Timer.

Before we get into the fundamentals of the game, we are going to combine together each of our individual elements, so that at the push of a button, our game runs! If you remember, each of our projects shared the fact that they were started at the push of a button, or when the I/O pad was HI. By tweaking each project to turn an I/O pad, connected to another Crumble, to HI at the right moment, we can cause a chain reaction! To get a better sense of what is going on programmatically, lets look at our new Colour Picker code.

Notice the addition at the end of the code. We’ve set C HI, which is connected to A on the next Crumble (running the Dice program). We then wait 100ms and set it LO again.

We’ve changed each program (apart from the Countdown Timer) so that it runs the additional code snippet after it’s finished it’s main purpose. We have changed the Countdown timer code so that it doesn’t wait for another input to reset the servo, rather it resets itself after a few seconds.

To get this to work correctly, we need to have common grounds (-ve). The easiest way to do this, like we have, is to use a single power supply.

This is only one of the ways to connect your projects up.

Lets look at the chain reaction in action!

Now we come to the game, which is played as follows. The aim is to come up with as many words as you can, which are as long as the number on the dice, within the time limit (one and two may be tricky, so you could remove them). The colour at the beginning relates to a bit of a forfeit which takes place during the round. These are as follows:

  • Red – Scattergories mode. If any of your words are the same as anyone else’s, they don’t count for anyone! You need to be unique to win.
  • Green – Hand switch. Swap your usual writing hand, for your non-dominant one.
  • Blue – Shout it out. Every time you write down a word, you have to shout it out.
  • Yellow – Normal. No bizarre rules, just write down as many words as you can.

Let’s look at an example.

Here we’ve ended up with green, five and G. This means that we need to write as many five letter words as we can, that start with the letter G, in 30s. But we have to do it with our non-dominant hand, so in my case I would swap to my left hand to write with.

And there we have our game ready to play! Clearly you aren’t limited to this version of the game. There’s a plethora of possibilities out there using these examples or combinations of your own.

If you have a go at this project, or any other, we’d love to see! Get in contact with us via emailFacebookTwitter or our Forum.