Categories
Gadgets Geekery Raspberry Pi

Ryanteck Raspberry Pi Serial Debug Clip review

When building projects on the Raspberry Pi that run ‘headless’ I’ve often found it necessary to connect to the Pi to see what’s going on, work out why it’s not working as I expected or to simply shut it down neatly without yanking out the power cable.

There are a few ways to do this – you could carry around a keyboard and monitor, hook them up to the Pi and see what’s what. The extremely useful and sadly getting rarer and more expensive Motorola Lapdock which I reviewed a while back works very well as a portable monitor / keyboard combination.

Or you could connect to the Pi using SSH if you’re both connected to the same network.

The third option is to connect to the Pi using a USB to Serial port converter. These are usually available as USB to TTL Serial Cable with a USB plug on one end and a series of female jumper wires on the other. Adafruit have a good guide on how to use one of these. Ryanteck have recently released a Raspberry Pi USB debug chip which works in the same way as the USB serial cables, but which is easier to connect to the Pi and includes friendly green and red LEDs to indicate data being sent back and forth. I recently backed this on Kickstarter so was able to get one to play with.

For this option you do need to carry round a computer, but as I discovered it works well with my tiny Toshiba Encore windows 8 tablet – and even with an Android mobile phone!

Raspberry Pi USB Serial debug chip
Lego spaceman has removed the important little jumper on the bottom left of the clip

Assembling the chip is very straightforward with the instructions on the Ryanteck website – although it’s worth mentioning that the version of the PCB supplied varies slightly from the images in the guide. The final version of the PCB includes a little jumper clip – this is quite important – with the jumper in place the Debug Clip will power the Raspberry Pi. It’s vital that the Pi is powered from either the clip or it’s micro USB port – the serial link will not work if the Pi is powered from both.

The RPi debug clip lacks any headers or sockets – it’s designed to sit on the Raspberry Pi GPIO pins underneath a hat or add-on board. In practice I found it a tight fit on the Raspberry Pi pins and a loose fit on a spare extension header I had lying around so I’ve used a 40 pin extra tall header – with this it’s possible to use the Rpi Clip with the Pimoroni Coupé style cases and have room to fit additional hats on top:

Debug clip sat on a 40 pin tall header, sat on a Pimoroni Coupé case
Debug clip sat on a 40 pin tall header, sat on a Pimoroni Coupé case

Despite having just one micro usb port it’s possible to use the debug clip on the Toshiba with a Micro USB Host OTG Cable – as there are a lot of very cheap Windows based tablets now available I imagine they all work in the same way.

To get the RPi clip working with the Toshiba Encore I installed the driver from the Microchip website, and then looked up the COM port the USB Serial port was using with the Computer Management window (right click on the Windows 8 start icon). In my case it was COM3. I opened up the Windows Telnet App PuTTY, chose a serial connection on COM3 at 115200 baud, hit enter and voila! – the Raspberry Pi login prompt appeared.

RPi debug clip
I do normally use this with a little keyboard, but it’s still very little.

It’s also possible to use the same cable with an Android mobile phone. I tested it with my bog standard Nexus 5 (which hasn’t been rooted) and a free app called DroidTerm – to connect hook up the Pi with the OTG to USB cable, make sure the header on the RPi debug clip is removed and use the following settings:

Droidterm screenshot
Basic connection options

When you first connect the screen will be blank – just enter the username you normally log in on your pi with (I think everyone uses ‘Pi’) and it will prompt you for your password. It’s a basic app – there’s no cut and paste, but for checking on things it’s fine.

Droid term /cat/proc/cpuinfo
Here’s some Pi info on a mobile!

The Ryanteck Raspberry Pi debug clip is available here for about 7 quid.

 

Categories
Activism Raspberry Pi Work stuff

Raspberry Pi powered General Election Swingometer

In the UK it’s election time again and the BBC are preparing to wheel out the latest version of their Swingometer. The BBC Swingometer dates back to 1959, and was a visual device for displaying the balance in seats won by the two main political parties. The Swingometer coined a whole load of phrases along the lines of a ‘swing away’ or ‘swing towards’ a particular party or candidate, and was well suited towards the simple days of two party politics.

Here’s version 1.0 back in 1959:

There's a chap with a pipe behind controlling the arrow
There’s a chap with a pipe behind moving the arrow (photo BBC)

The BBC have more or less stuck to the same device for every election since, although sadly in the same way that CGI ruined the Star Wars films, Swingometers have recently become more and more complicated. This is perhaps also a consequence of the UK moving to multi-party politics where working out who exactly in power after polling day is getting a bit complicated.

Here’s version 14.0 from 2010:

There's just a big green room
There’s just a big green room (photo BBC)

In a tribute to the original, the charity I work for – Concern Worldwide have been using a Development Swingometer, which pays homage to the original 1959 version and tracks the number of candidates who have signed up to support Concern’s 5 pledges on fighting global poverty and protecting international aid (you can tweet them on that page with some code I mashed up using TheyWorkForYou.com and YourNextMP.com).

https://twitter.com/ConcernUK/status/593761711020183552

Building a Raspberry Pi powered Swingometer

As our low-budget version is a bit simple, for a bit of fun I thought I’d build a slightly more technical version that updates itself automatically. My updated Swingometer uses a servo to move the arrow, and a Raspberry Pi to fetch the ‘swing value’ from a web page when you push the big friendly button. The code I’ve used can be edited to fetch more or less any numerical value from a web page and turn it into a ‘swing’ so It should be possible to repurpose this into a political swingometer, or something that displays anything with a value of 1-180 (the angle of swing possible with a servo).

Push the button for results
Just push the button for the latest results

The back of the frame (£5 from Wilko) shows the Raspberry Pi model A and a little slice of Pi board I soldered up. There are two buttons – the big friendly update button for the front and a safe shutdown button on the back, so I can run this without a screen and keyboard.

Here's the back with an arcade machine button and the wiring to the servo
Here’s the back with an arcade machine button (white wires) and the wiring to the servo (brown – red – yellow wires)

The method I’ve used to control the servo is similar to RaspiTV’s Raspberry Pi flag waving post – although I opted for the version detailed in the Raspberry Pi cookbook over Adafruit’s single servo control. For my power supply I used a D-link powered USB hub to supply both the Pi and the Servo via separate USB cables. This results in a slightly wobbly update of the Swingometer arrow, which suits me fine. For more precise control you can use a dedicated servo control hat which can control up to 16 separate servos.

https://twitter.com/kimondo/status/595957624614563841

For the code I modified the Raspberry Pi cookbook tutorial code to fetch a value from a web page using Beautiful Soup. You can install this on the pi using:

sudo apt-get install python-beautifulsoup

Note that this installs version 3 – but you’re still able to do lots of clever things to grab content from web pages. If you want to build a political swingometer I’d suggest grabbing values from the election forecast page. There’s a lot more information about using Beautiful Soup on the web page here.

Here’s the code I’ve used to update the swingometer:

import RPi.GPIO as GPIO
import time
from BeautifulSoup import BeautifulSoup
import urllib2

#change this bit
url="http://www.kimondo.co.uk/swingometer-control/"
page=urllib2.urlopen(url)
soup = BeautifulSoup(page.read())

value = soup.find('span',{'style':'color: #99cc00;'})
value = value.next
value = float(value)

print value

GPIO.cleanup()
GPIO.setmode(GPIO.BCM)
GPIO.setup(18, GPIO.OUT)
pwm = GPIO.PWM(18, 100)
pwm.start(5)
t_end = time.time() + 1

while time.time() < t_end:
        print value
  angle = value/100.0 * 180
  print angle
        duty = float(angle) / 10.0 + 2.5
        pwm.ChangeDutyCycle(duty)

exit()

An alternative I considered was using the Sentiment 140 twitter sentiment tracker API – this tracks positive and negative sentiment towards keyword searches on twitter – although it seems to get fooled by ironic tweets.

If you’ve been inspired to build a Swingometer please share it in the comments! One day I’d quite like to build something like the Weasley clock.

You can ask your election candidates to support Concern’s 5 pledges to fight global poverty and support development here and my fantastic blog about the Development Swingometer on Concern’s website.

Categories
Arts Code Gadgets Geekery Raspberry Pi

ASCII camera with the Holga 120d

So now I’ve finished my digital Holga project, one of the things I wanted to do was to get a bit creative with it – so here’s my first attempt at an ASCII art generating camera.

Holga 120d ASCII text image
High contrast images work best.

This uses the ASCII art script written by Steven Kay, please visit his blog to find out more – I’ve modified the original script to use the python picamera library – this helps speed up the image resize. There’s also a timestamp added to the text file which uses the same script I wrote about in my previous Holga post.

If you just want to run Steven Kay’s script you’ll need the python imaging tools – install with

sudo apt-get install python-imaging

Here’s my modified script:

'''
ASCII Art maker
Creates an ascii art image from an arbitrary image
Created on 7 Sep 2009

@author: Steven Kay
'''

import time
import picamera
from PIL import Image
import random
from bisect import bisect

# greyscale.. the following strings represent
# 7 tonal ranges, from lighter to darker.
# for a given pixel tonal level, choose a character
# at random from that range.

greyscale = [
            " ",
            " ",
            ".,-",
            "_ivc=!/|\\~",
            "gjez2]/(YL)t[+T7Vf",
            "mdK4ZGbNDXY5P*Q",
            "W8KMA",
            "#%$"
            ]

# using the bisect class to put luminosity values
# in various ranges.
# these are the luminosity cut-off points for each
# of the 7 tonal levels. At the moment, these are 7 bands
# of even width, but they could be changed to boost
# contrast or change gamma, for example.

zonebounds=[36,72,108,144,180,216,252]


#take photo

with picamera.PiCamera() as camera:
                        camera.capture('image.jpg');

# open image and resize
# experiment with aspect ratios according to font


im=Image.open(r"image.jpg")
im=im.resize((160, 75),Image.BILINEAR)
im=im.convert("L") # convert to mono

# now, work our way over the pixels
# build up str

str=""
for y in range(0,im.size[1]):
    for x in range(0,im.size[0]):
        lum=255-im.getpixel((x,y))
        row=bisect(zonebounds,lum)
        possibles=greyscale[row]
        str=str+possibles[random.randint(0,len(possibles)-1)]
    str=str+"\n"

print str

date_string = time.strftime("%Y-%m-%d-%H:%M:%S")

text_file = open('image' + date_string + '.txt', "w")
text_file.write(str)
text_file.close()

There are lots of settings to tweak – the image above was generated by the script – and bear in mind this is designed to be viewed with black text on a white background. Perhaps I’ll see if I can dig out an old dot matrix printer from somewhere.

For a blog of ‘photos’ updated whenever I take them and am in range of WiFi check out:

http://holga120d.blogspot.co.uk/

This emails the ASCII art in HTML format to blogger whenever I take a photo (and the Pi Holga is in range of the internet).

For more about the Digital Holga check out my previous blog posts on the hardware and building the case.

Categories
Activism Websites Work stuff

TweetyourMP.com launched

Since I’ve upgraded my hosting, one thing I’ve been wanting to do was to find a proper home for my Tweet Your MP script.

This is a php based script that looks up a UK parliamentary constituency given a postcode, and then returns the details of the MP using it’s own database. It’s been a handy resource for a few work projects, and since being published on GitHub as an open source project has been downloaded and used by a few other organisations as well.

So I can now reveal tweetyourMP.com

Tweet my MP
Version 1, still in BETA
  • The data set has been updated – it now includes twitter accounts for 495 MPs
  • MP Email addresses and websites (where available)
  • Notable additions since the last update include Kate Hoey and Zac Goldsmith
  • the script is running on it’s own virtual host so it should be much faster.
  • The updated dataset is available as a google doc.
  • There’s now @tweet_your_MP on twitter which is an account which follows MPs who tweet
  • You can fork the project on GitHub

The next step of the project is to provide a widget version of the tweet your MP tool which can be added to blogs easily.

Also on the horizon is a completely hosted solution that makes use of the open source postcode to constituency database.

As always this is made possible by the very useful TheyWorkForYou.com API and the PHP-API interface script originally written by Ruben Arakelyan.

If you have any corrections to the data, please let me know.

A few facts and figures about UK parliamentarians

In total 86% of Labour78% of Liberal Democrats and 72% of Conservative MPs are on twitter.

For MPs not on twitter at several have parody accounts registered in their names, including Iain Duncan Smith who has over 26 thousand followers.

22 MPs don’t even have websites.

Categories
Arduino Gadgets

The smallest USB mechanical keyboard in the world*

Sometimes it’s annoying when your favourite old school mechanical keyboard lacks some of the modern function keys that we’ve grown used to using in recent years. Or you might be re-purposing a keyboard for a use it wasn’t really designed for – I have a lovely chicklet keyboard with my Raspberry Pi Motorola Lapdock hack which lacks both left and right windows keys.

You can of course usually find a way round these limitations by hitting control and frantically hammering in the number of the function key (if you can remember it) – but sometimes that doesn’t work. For example the ArcEm emulator that runs on the Raspberry Pi RISC OS requires both left and right windows keys to be pressed simultaneously to exit.

Fortunately to the rescue is this – the smallest USB mechanical keyboard in the world (probably):

Smallest USB keyboard in the world
Now I just need a portal gun

The blue Cherry MX keys are illuminated, and for 10 seconds when you first plug it in you can remap them to almost anything (including words and short phrases). I did find a couple of programmable USB keystrips that offered similar functionality, but these were a bit expensive and lacked mechanical keys. If you shop around for the parts you can build this for less than £15.

Build guide:

First you need a few parts:

  • An Adafruit USB trinket (5v) In the UK available from Pimoroni
  • 2 x MX cherry keys (try ebay – e.g. this listing)
  • 2 x keycaps (lots on Amazon)
  • 2 x 3mm LEDs (and a 50 ohm resistor)
  • A mini (the older not micro) USB cable
  • Some wire
  • A suitable box (the one I used was a little on the small size – something 6cm x 3cm x 3cm might be better)
  • Craft knife, dremel, soldering iron, multimeter with continuity tester

This project does require a bit of soldering – I opted to solder the pins onto the the trinket, and then attach the wires using female jumper cables – for a neater build you could solder the wires directly between the cherry keys and Trinket. If you’re opting for total neatness you can also solder the USB wires directly to the underside of the Trinket as there are some surface mount tabs.

A costlier but wireless alternative to the Trinket is the Adafruit Bluefruit EZ HID keyboard controller again available from Pimoroni in the UK.

Putting it together

This is based on the Adafruit USB Trinket – a very cut down minimalist Arduino clone (it runs some simple Arduino code no problem, but needs it’s own version of the programmer tool). Adafruit have a tutorial which shows how to wire up a Trinket to act as a USB HID along with a couple of code examples.

First step is to try out the Adafruit tutorial on some breadboard – if you get stuck head over to the forums where Frank can help – to get this to work on my Mac I needed to plug the USB cable into a USB 2 port directly (not via a hub) and use the experimental library. Make sure you’re using Adafruit’s version of the Adruino IDE – all the info is on the Trinket page.

Adafruit Trinket as a USB keyboard
Trinket as a USB keyboard

Plug this in and try out uploading the sketch – when you first connect the Trinket the red LED will blink for 10 seconds – you have to hit the upload button on the Arduino IDE app in this time for it to work. Once the red LED has stopped blinking, your computer should recognise the keyboard.

We’re using exactly the same circuit, with the exception of adding 2 LEDs in series. The trinket has a 5v pin which supplies just about the right amount of power for the LEDs I used but check with an LED circuit calculator to see if you need to add a resistor. The Cherry switches have 2 small holes for the LED wires to sit in.

Next we need to prepare the keys and a box for them to sit in – here for some Dremel action!

Photo of USB keyboard before assembly
all the bits, prior to wiring

The Cherry keys are wedge shaped so cut a hole slightly too small and then widen using the Dremel – they are about 12mm square. I did find this a little messy and resorted to using a glue gun to tidy things up! for a neater build you could try a hot knife cutter, or for the über neat build 3d print a proper case. Fortunately once the keys are in place you don’t really see the holes.

Once the keys are fitted, solder on some wires. Note that the pins from the cherry keys are quite brittle (they’re designed to sit in a printed circuit board) so avoid bending them if possible.

The wiring arrangement I used was this:

Cherry keyboard wiring
Cherry keys viewed from the underside

Make sure the LEDs are wired in series (+ to – to + to -) – you can identify the positive (anode) lead on the LED as it’s the longer one. The LED and key circuit can all share the same ground connector. It doesn’t matter which way round you add the resistor.

Once you’ve got everything soldered together, plug it in and test – especially before putting the box together. I found cramming it all into the case a bit tricky but managed it just. I cut up a USB mini cable and re-soldered the wires to fit in the box. As I mentioned previously – soldering the wires directly to the Trinket would save a lot of space.

USB keyboard internal wiring
here it is, tight fit.

Finally enjoy your mechanical keyboard! – although this has only 2 keys, the action on the Cherry MX blues is so nice I’m now thinking I might need to invest in a proper full size one.

*probably – I’m not expecting a call from Guinness just yet.

Update – I’ve potentially been outdone with the single key keyboard which has been launched on Kickstarter.

Categories
Code Gadgets Geekery Raspberry Pi

Holga 120 D

This is an update to my original Raspberry Pi Holga camera case project.

Earlier this year Holga Direct created a digital version of the Holga – the 120d as an April fool joke – although my version lacks the 73 megapixel sensor and retina back display it does actually exist, can take nice pictures and is fairly easy to build yourself if you’d like to give it a try.

The aim of this is to build a neat case which fits the Raspberry Pi and camera module, and to do a bit of experimenting with the GPIO (General Purpose Input and Output) pins to use them to control various aspects of the camera. Lacking instant feedback and having no idea what you’ve captured until you take it home also fulfils some of the ideas behind retro analogue photography made popular by Lomography. It also looks a bit hipster.

Holga 120 d Raspberry Pi camera
Shutter release and power on the front lens

This is a fully working Digital Holga 120d – it used the case from a broken Holga, unfortunately it doesn’t use the original plastic lens (although I have kept this) as the Pi Camera board has it’s own built in lens, however it is now possible to use screw on lenses and filters.

The case is now finished but I have made a few changes since my last post:

I’ve lost the external USB port as there wasn’t quite enough space inside the case to fit the USB plug – I am now using a nano wifi adapter inside the case – specifically the Edimax EW-7811UN adapter which works well with the Raspberry Pi model A and fits inside the case.

Along the way I’ve added a few extra parts:

  • A 49mm adapter ring on the front lens – it is now possible to add filters – this is a zomei 46-49mm adapter ring (similar to this one) which screwed in to the original Holga plastic lens after using a dremel to sand down the holga lens until it fitted.
  • 3.5mm plug for external camera trigger – this is a stereo headphone socket with 2 wires attached. Am using a mono 3.5mm cable to use as a cable release driver as I think it’s some kind of standard.
  • led indicator (in the viewfinder – which glows red to indicate a picture is being taken )
  • Optoisolator flash circuit – this is an LED attached to an image sensor – the model I’m using is rated to control very high voltages.
  • A 3 position rotary switch – to select between video, still photos and program mode. This is a 12 way switch so i’m only using a few of the contacts. I used a big chunky switch I found on ebay which makes a satisfying click when you turn it – it did fit after a dremel was used to cut a larger hole. I’ve used a tap washer to fill the gap between the switch and the camera case.
Holga 120d Raspberry Pi Camera Case
Here’s the 3/4 view with the big clunky switch. It will switch something eventually.

I’m currently powering this using a (rather big) Anker USB battery – will likely use something smaller in due course but the Anker battery seems to last forever and powers the Pi with the Wifi adapter with no problems at all.

The next step is to build the hardware to connect the various inputs and outputs to the Raspberry Pi. I’ve been experimenting with these using breadboard and hope to solder it all neatly together – with details – for my next project post. Essentially I need to wire 3 switches (shutter, 2 rotary switch positions) and 2 LEDs (indicator, optoisolator) to the GPIO.

Then finally there’s the matter of some software to pull it all together. At the moment I’ve been testing using the rather useful BerryCam iOS app – although it seems ironic to be using a device with it’s own much better built in camera to control the camera of another computer remotely, it’s a useful app to test things with. If you use the instructions in the first bit of my post about using the Pi as an Adblock server you can also set the IP address to be the same each time.

Update: I’ve added the inputs and 2 LED outputs to the GPIO on the Raspberry Pi – check out this post for more details, circuit diagrams and code.

Finally here’s a selfie in the mirror:

BerryCam Holga 120d self portrait
Hello me

 

 

Categories
Geekery Raspberry Pi

How to play the original 8-bit Elite on a Raspberry Pi

Ok, so after my last post about running the Archimedes 32-bit version of Elite on RISC OS on the Raspberry Pi I got a few comments about running the earlier (and more authentic) 8 bit version on modern hardware. So I thought I’d have a bit of a play and try out a few options for running the original version.

Probably the easiest way to get a taste is to run the NES version on an emulator – Elite co-creator Ian Bell describes this as “the best way to re-experience the feel of 8 bit Elite“.

There are NES emulators available for almost any platform – here it is running on my Android 4 MK802 lapdock using iNES. You can download the ROM freely (and legally) from Ian Bell’s website.

Elite running on the iNES emulator on an Android 4 MINI PC
Cobra mk III

If you find the display corrupts you need to make sure it’s set to PAL and not NTSC or ‘auto’ . iNES has a nice function where you can remap keys to the various buttons, which is handy when using an external USB keyboard with the MK802.

It works well- although Elite’s many keys are replicated through combination key presses which takes a bit of getting used to. You can fly, shoot, get shot at, and crash at docking.

As I mentioned in my previous post – it’s rather fun to play Elite on the Raspberry Pi computer – the original BBC B’s spiritual successor, which also shares a creator with Elite.

The Raspberry Pi also has (various) NES emulators available for it – although I’ve yet to find one that can run Elite smoothly and without any issues (consider this a work in progress). However you can emulate the machine where it all started back in 1984:

How to emulate the BBC Micro  (model B) on a Raspberry Pi (model B)

Bridge of the Cobra Mk III image from the Elite user manual
Bridge of the Cobra Mk III – uncanny how the console of a 31st century starship looks a bit like a 1981 microcomputer…

It is possible to run the original BBC B version of Elite using the !BeebIt emulator – this is an emulator that runs in RISC OS.

Compared to the linux and android based emulators available this runs much more quickly since RISC OS is a very lightweight operating system.

To relive the original Elite – I’ve prepared a step by step guide – make sure you do all this on a Raspberry Pi running RISC OS – particularly unpacking the zip files.

First create an SD card running RISC OS or just download the NOOBs installer.

RISC OS uses a 3 button mouse – you’ll need one to access menus using the middle button – applications have a ! at the beginning of their name, and shift-click opens the application folder. There’s more RISC OS info available here.

Note that it also helps to have a standard, full size keyboard.

Then download !BeebIT – of the two versions available I’ve been using Michael Foot’s.

Extract the archive on your Raspberry Pi by dragging and dropping the download file, and then double clicking and dragging the !Beebit application file to a new folder. (Note that RISC OS is very drag and drop orientated).

Next you’ll need some BBC ROMs – the ROMs download on Michael Foot’s page contain both the OS2 and DFS ROMs you’ll need:

Download

Open up this archive as before – this will contain a !Beebit application icon – just drag and drop this over the !Beebit application you extracted earlier. (Application files on RISC OS are folders containing the program and needed files – by dragging and dropping the ROM file you are just adding the files you need)

Double click !BeebIT to run – it should appear on your icon bar. If you get any errors for missing ROMS, check the steps above or try downloading them individually. f12 will exit the emulator back to the RISC OS desktop.

Download BBC Micro Elite extract and set the type to DFSImage (the icon should change to a floppy disc) – to do this click the middle (menu) button on the file > File ELITEBBC/SDD > Set type and change “Data” to “DFSImage”.

Double click on the image file to run.

Once in !BeebIT type *!BOOT (on my keyboard the @ was *)

then enjoy!

The classic loading screen
The classic loading screen

Have a go at playing with the settings – you can choose a high quality display mode, or set CPU speed to Full Speed. If you’re feeling a bit more adventurous !BeebIt also emulates the Master 128 which ran a full colour version of Elite which is similar to the NES version – you’ll need to download the correct ROMs but all the info is included in the !BeebIt help file (middle click on the !Beebit application App.> ‘!Beebit’ >Help)

Commander Jameson
Commander Jameson

The easiest way to save your progress is to hit f12 to return to the desktop and then the middle button on the !Beebit emulator icon to then choose Save >Save as snapshot. Dragging the snapshot file back to the !Beebit icon will reload your game in the same state you left it. Note for some reason double-clicking on the snapshot icon to load it won’t work.

If you’re interested in Elite you can read a bit more about the 32-bit version of the game in my previous post – or check out the Elite Dangerous Kickstarter which is collecting pledges for a 21st Century version.

Categories
Gadgets Geekery

MaKey MaKey + Moleskine notebook + Graphite pencil = sketchy controller

As part of my ongoing kickstarter addiction I’ve recently acquired a MaKey MaKey – a sort of universal keyboard adapter gadget based on an Arduino-type microcontroller, that lets you turn virtually anything that conducts electricity into a USB keyboard or mouse.

MaKey MaKey board
It even lights up when you plug it in..

The board comes supplied with a pack of crocodile clips and a nice long USB cable – on the MaKey MaKey website there’s a list of ideas to try (apparently bananas work well as a piano). All you have to do is find something suitably conductive, connect them up with the clips, and away you go.

The simplest interaction is creating a space bar input – this Olympic hurdle game from the ONE Campaign works well as something to try.

I’ve done a bit of experimenting to see what conducts with the aim of making controller doodles in my moleskine notebook. Conductive paint from these guys works – interestingly metalic effect paint and ink doesn’t work (I suspect as the metal is in a suspension).

The easiest and most sketchable I’ve found is using a big chunky graphite pencil like this one KOH-I-NOOR Jumbo Woodless Graphite Pencil 6B available from amazon for a couple of quid:

image of moleskine jump button and MaKey MaKey
hitting the gap between the U and the M creates a space bar press

You have to press quite hard with the pencil to get a good circuit – shorting the gap between the U and the M with your finger is enough to register as a space bar press:

Playing the race against hunger game with a MaKey MaKey
Ignore my score, it’s hard to hit jump and hold a camera at the same time..

So there you are – a sketchable, moleskine portable control interface! (even if it does get a bit smudgy after extended play).

Check out the ONE Campaign race against hunger game here.