FIELD TESTometimes bigger is better, or rather,
sometimes you just need a larger
display for your project. Think really
large, like Times Square-TV large. Well,
that’s exactly what these panels could be
used to build. You can find them all over
the place in urban areas in the form of large-scale video
advertising displays. They can be chained together to
create really large animated, and full colour, displays.
That being said, there are a few considerations when it
comes to creating large video screens.
As displays get bigger, especially when thinking
about full colour display, the prices can skyrocket.
However, the Adafruit 32×32 RGB LED Matrix
Panel still comes in at a respectable $39.95. That’s
not too bad for 1024 RGB LEDs in a 7.5” × 7.5”
form factor. Yes, it gets expensive if you needS
Adafruit 32×32 RGB LED
Matrix Panel
ADAFRUIT $39.95 adafruit.comdozens of them, but in many instances one will
work just fine.
Something else to consider when using large
displays is the horsepower required to drive them- or, in our case, the speed that is needed to
control them effectively. These particular panels
were designed for high-speed FPGAs or similar
processors. They rely on the image being drawn
over and over at a high speed, something that a
typical microcontroller can’t do very well since a lot
of data needs to be processed quickly. Your best
bet is to use a Raspberry Pi with an RGB Matrix
HAT or Teensy microcontroller, rather than the less
powerful Arduino microcontroller.
Another thing you’ll need to consider is the
power required for the panels. Fortunately, the
drivers are built into the back of the panel, and the
power is low voltage, requiring only 5 volts and 4
amps when all the LEDs are on full power. There
are plenty of guides on the Adafruit website to help
you get started quickly, no matter what controller
you choose.
One of my favourite projects that uses this
display is SmartMatrix Animated GIF Player by
Louis Beaudoin. It uses a microSD card and
a Teensy to play back animated GIFs on the
32×32 RGB display. With the simple addition of a
translucent covering, the pixels are blended and
smoothed out, which looks great with the looping
animated GIF. You can check out the complete
tutorial at hsmag.cc/sBBbNS.
Another cool project that uses this display is
the Raspberry Pi LED Matrix Display by Tony
DiCola; hsmag.cc/crohbf. In this build, Tony goes
over how to use the rpi-rgb-led-matrix library, a
Raspberry Pi 2, and a few other components to play
low-resolution games, movies, and images. And
although this won’t complete with your new 4K TV,
it still has a redeeming retro charm.
When you need
a large display,
this is the board
to consider.VERDICT
9 / 10
Left
If the 1024 RGB LEDs
still aren’t enough
for your project, you
can easily add more
panels to create
larger displays
Credit
Adafruit licensed
under CC