Introduction to the LED UI Project
This project and this website is about making applications
for the kind of LED grid (also known as LED
Matrix) devices that are available for
single board computers or micro-controllers, but you can also
them on a normal computer using your normal screen, for
to emulate an LED grid.
Obviously, this is a whimsical endeavour, and is meant to be
fun. A load of weird lights is an entertaining but very niche
way to read and interact with a computer.
It might be difficult to write a sequel to War and Peace with
this format, but it works quite well for certain simple games
as well as: "rain 20 degrees, meeting at 11, don't forget the
milk" or whatever you want to be notified about. Even
music player could be controlled through an LED grid.
If you are making an application for LEDGrids, I would love
to hear about it.
Why are we here?
I realised that my Raspberry Pi Sense HAT, an 8x8 LED Grid,
used 25 times less power than my little DSI touchscreen and
50 times less power than my HDMI monitor.
Having spent my whole childhood playing Tetris, my brain is
already trained to read coloured blocks from a grid. Therefore
I decided to see how far I could push the concept of using an
LED grid with a small board computer. Could it replace a
desktop computer and monitor in my house (e.g. for
notifications and certain other tasks), saving electricity
and thus helping the planet?
This was my first attempt at an LED grid based
It aimed to show me a visual summary of my
communications while away from my main desk, e.g. on the
breakfast table, etc.
The symbol in the top right is telling me that today it
will be cloudy with rain (i.e. it is actually meant to
be a little picture of a rain cloud).
However, I can cheer up because the two columns of
stacked dots are telling me I have five emails in my
Gmail and three Twitter notifications.
The next logical step was to be able to read email subjects,
tweets, etc on the device. So when I selected a dot using a
joystick, it would scroll the text across the screen using
This however was slightly slow and fragile, i.e. if in my
impatience, I got bored and moved my gaze away, I could
easily lose a few characters and have to wait until it had
finished scrolling and then start it scrolling all over
What I really wanted was a way to have several
characters on screen at one time. I realised that if each
character was encoded in a vertical 4 square block, I
could see up to 16 characters on screen at once.
Later, come back and see if you can read this message.
LED UI clearly takes off, especially in the 23rd
Century. Enterprise science officer and first officer
Spock, has all the information he needs from four colour
matrices. No fancy pictures, no talking robots, no
Incidentally, Matt Jefferies, art director and
production designer on the original Star Trek series was a
distinguished World War II aviator, and took the concept
of 'space navy' seriously in his designs, using military
technology and design principles.
In the Predator movies, the creatures control their
masks and weapons using these four little panels. I don't
want to spoil the plot, but we can say it is the last
display a Predator will ever need.
Green Rain from the Matrix films, beautiful if somewhat
slightly impractical. These days, even nano can colour