ShrimpKey – make your own MakeyMakey – part 1
Do you really like the MakeyMakey, but find it too expensive?
Do you need enough MakeyMakey’s for your class/group, but don’t have the money to buy these?
Do you like to make something?
Read here how to make your own MakeyMakey (well…. your own ShrimpKey).
What is a ShrimpKey?
With a ShrimpKey you can make your own keyboard with everyday objects. Connect i.e. a couple of bananas to the ShrimpKey and the bananas are the keys of your keyboard. Then connect your ShrimpKey to your computer with a USB-cable (no need to install any software) and you can play a piano in Scratch with your bananas, look here.
The ShrimpKey is almost capable of the same things as a MakeyMakey.
There are three differences:
- the ShrimpKey has 9 connectors (MakeyMakey: 18)
- the ShrimpKey can only type letters (MakeyMakey: can move the mouse also)
- the ShrimpKey will cost you around $ 7 (MakeyMakey: $ 50)
OK, there is a fourth difference (and I find this the most fun and important one):
- the ShrimpKey is DIY (MakeyMakey: off-the-shelf)
If you don’t like the last difference, or if you don’t find this important and you don’t mind spending more money, no problem. Please buy a real MakeyMakey.
That’s easier (but I hope you will make a ShrimpKey!)
Prerequisites
Some knowledge about electronics.
Experience with soldering electronics is a must (you don’t need to be an expert, but I won’t explain how to solder).
2 part
The ShrimpKey consists of twee parts.
- Shrimp
- ShrimpKey-shield
I didn’t invent the Shrimp, they did that in the UK.
A Shrimp is a substitute for the Arduino Uno, but only cost a couple of dollars (around $ 4)
More information about the Shrimp can be found on http://shrimping.it.
I did alter the design of the Shrimp, so that add-on boards (shields) can be connected.
The first shield is, as said, the ShrimpKey. It isn’t my idea; it’s the idea of the inventors of the MakeyMakey.
But I did invent the way to make a MakeyMakey with a Shrimp.
Because you also can do a lot of fun stuff with the Shrimp (also with Scratch, I will blog about that later), I’ve chosen to make the ShrimpKey in two parts.
In this way you can use the Shrimp also without the shield.
If you want to make a ShrimpKey in one piece, please have a look at my first design.
Which tools do you need?
- soldering iron (with adjustable temperature)
- solder (for electronics)
- small wire cutter (with a sharp tip)
- sharp knife
- drillbit for metal (3,5 mm)
- hacksaw
- wire (preferably flexibel and eventual in multiple colors)
Which components do you need?
I buy my components at Tayda Electronics. This is a cheap webshop in Singapore and – if you’re not in a hurry – the shipping costs are a couple of dollars.
They regularly have discountscodes on their Facebook-page. Check it out before ordering (and always try the last discountcode, even if the due date has past).
I will mention the article codes of Tayda, because I order my components there. Please have a look at the specifications, if you’re going to buy your components elsewhere.
Before I give the shopping list, please read this:
- the chip you need (ATmega328P-PU) must have the ‘Uno Bootloader’ on it. If you order from Tayda, you will get a blank chip and you yourself have to ‘burn’ the bootloader on it (you need a Shrimp or Arduino for this). You can find these chips (with bootloader) on eBay (and probably cheaper). If you’re going to burn the bootloader yourself, please look at this great HowTo: Burn a bootloader to a blank chip – note: you probably also need the ‘not necessary’-components]
- you also need 2 Zener-diodes with a maximum of 0,5W. Tayda only has 1W-diodes. I’ve asked them to add 0,5W-ones to there assortment. If they do, I will post it here and on Twitter.
So, you have to buy these somewhere else (at the moment). - you also need to put the firmware on the chip (that’s something different than the bootloader). For this you need a CP2102/CP2104. You can buy them here. I haven’t tried the CP2104 (only the CP2102) myself, but according to ShrimpingIt, they should work (even better).
- some plastic pads are very handy to stick under the Shrimp (see photo). I’ve bought them at my local hardware store (tesa Protect Anti-noise/Anti-slip).
The components
Shrimp:
- 1x ATmega328P-PU (A-854)
- 2x 22 pF capacitor (A-523)
- 4x 100 nF capacitor (A-4008)
- 1x 10 uF capacitor (A-4534)
- 1x 10 KΩ resistor (A-2115)
- 1x 100 Ω resistor (A-2051)
- 1x 1N4148 diode (A-157)
- 1x 16 MHz crystal (A-230)
- 1x button (A-5144)
- 1x blue LED Ultra-bright 5mm (A-407)
ShrimpKey:
- 18x 10 MΩ resistor (A-2063)
- 1x 2.2 kΩ resistor (A-2087)
- 2x 68 Ω resistor (A-2086)
- 1x 100 Ω resistor (A-2051)
- 1x USB-B-connector (A-437)
- 1x green LED Ultra-bright 5mm (A-057)
- 2x 3.6V Zener-diodes (max. 0,5W) (not at Tayda)
For both (so you have to buy these once!):
- 1x pin-strip (A-197)
- 1x angled pin-strip (A-199)
- 2x pin-connector-strip (A-196)
- 1x stripboard (A-5031)
- 3x 1ft blue wire (A-4993) (they have multiple colors, with different article codes)
Oh, and you need a USB-(printer)cable (USB A -> USB B).
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
8 Comments: "ShrimpKey – make your own MakeyMakey – part 1"
Published by: Clemens Date: 11 January 2014
Beste Sjoerd,
Verder heb ik een vraag over part 1 & 2. Kun je hiervoor ook een standaard Arduino print gebruiken ? (Is deze pin compatible ?) Ik heb namelijk nog een Arduino Duemilanove liggen die ik graag zou willen hergebruiken.
Vast bedankt voor je aandacht . Groet !
Published by: Sjoerd Dirk Date: 11 January 2014
Als de chip op de Duemilanove gelijk is aan de ATmega328P-PU (en volgens mij is dat zo), dan kan dit idd.
Je hebt dan alleen het ShrimpKey-shield (deel 3) nodig.
Let echter op de pinnen van de connectoren; door een ontwerpfout is de afstand tussen digital I/O 7 en 8 op een Arduino niet gelijk aan één pin.
Hierdoor zul je waarschijnlijk niet makkelijk een stripboard erop kunnen zetten.
Published by: onk Date: 15 July 2014
Did you mean 16 MHz in the parts list ? 16000Mhz = 16Ghz.
Anyways, very useful thank you,Cheers
Published by: Sjoerd Dirk Date: 15 July 2014
Yes, I do mean 16 MHz. I’m going to change it. Thank you.
Published by: Tails0630 Date: 14 December 2014
I found an ATmega328p-pn. It will work?
Published by: Sjoerd Dirk Date: 15 December 2014
I don’t know. If it’s fully compatible with the atmega328p-pu then it should be. But if it’s slightly different, it’s probably possible. But you have to try it.
Published by: Situs84 Date: 07 July 2015
I was looking at the zener diode. You labeled “(max. 0,5W)”. did you mean to put 0.5W or did you mean from 0 to 5 watts?
Published by: Sjoerd Dirk Date: 09 July 2015
I mean a half Watt (0.5W).