LED Hacks

1908 Articles

Overhauling LED Marquees

November 14, 2008 by 11 Comments

led-sign

In a previous job, [sprite_tm] was responsible for wrangling many different LED text ad marquees. The hardware was fairly simple and he always figured they could be pushed much further with a little work. He recently acquired ten 32×16 LED displays a decided to see what he could do with them. By the end of the project, he had full motion video running on the display. This is a great project to read up on if you’ve ever wondered about LED matrix displays. He starts by reverse engineering the electronics on the board. He then attached an ATmega88 to drive the display module. Multiple display modules were daisy chained together over serial. The article covers PWM control and refresh timing as well. Check out one of a few demo videos below. Continue reading “Overhauling LED Marquees” →

Stribe 1 Kits Available

November 13, 2008 by 11 Comments

stribe

We first spotted the Stribe music controller at Maker Faire. [Josh Boughey] has since refined the controller’s design so that it can be constructed in a modular fashion and it’s being sold in kit form by Curious Inventor. The kit has two columns of 64 LEDs and a Spectra Symbol SoftPot for control. You can daisy chain eight modules together using a ribbon cable. It uses SPI control, with a separate wire for the data line (not in the ribbon). An Arduino is used to hook the controller to programs like Max/MSP.

Improved LED Menorah

November 13, 2008 by 7 Comments

Reader [Mike] was not too impressed by design in a recent post we did on an LED menorahs. Doing what any self respecting hacker would do, he designed and built a better one then sent it in to us. He just happened to have an AVR ATtiny13 sitting around, so he used that for the brains. It has single button operation, is powered by 2 AA batteries, and even simulates the candles burning out. His custom PCB turned out quite nicely as well, the power plug connects to the batteries in a way that uses them as a base. Check out his site for detailed plans and source code. Great job [Mike].

Meggy Jr RGB Portable Game Platform

November 12, 2008 by 7 Comments

meggy

Evil Mad Scientist Laboratories have just announced the release of the Meggy Jr RGB, a fully programmable handheld console with an 8×8 RGB LED matrix display. Like its big sisters Peggy and Peggy 2.0, the Meggy Jr is driven by an ATmega168 microcontroller and is made up of a bank of fully addressable LEDs. Unlike its siblings, the device boasts six buttons and the ability to be mounted inside of a custom case (or “handle set”) constructed from plastic or wood, drastically altering the look of the console. Using the popular open-souce Arduino environment, users are able to write custom software for the device. While it works great as a game console, of the many possible configurations and suggested uses, we think “disco floor for your Lego minifigurines” is the most amusing.

Weasure, A Scale That Weighs And Measures

November 9, 2008 by 2 Comments

weasure

[John Peterson] created this postal scale device for a Renesas design contest. The Weasure not only calculates the package’s total weight but the dimensions as well. He built it using a SKP16C62P evaluation board that had an LCD, pushbuttons, and indicator LEDs. The original DigiWeigh parcel scale was modified to provide PWM output and tare control. He embedded photoresistors every inch along each axis. They were angle slightly upward and the surroundings were painted black to minimize reflection. The Weasure outputs everything via a serial connection so it can be used with shipping software to generate postage.

LED Menorahs

November 9, 2008 by 5 Comments

We’re barely past Halloween and people are already working on their next LED based holiday decorations. For Hanukkah, Gizmodo pointed out the PCB menorah pictured above. It uses a set of DIP switches to control which LEDs are lit. A couple years ago, Evil Mad Scientist Laboratories put together a tutorial for building a more minimal LED menorah. Each of the nine LEDs are soldered directly to the legs of an ATtiny2313 microcontroller. Every time you power up the device an additional LED is lit. [Ori] liked the project and decided to take a slightly different approach. He used an LM3914 DIP18 LED bar driver. A potentiometer controls how many of the LEDs are illuminated.

Minimalist LED Light Detecting Candle

November 5, 2008 by 17 Comments

[youtube=http://www.youtube.com/watch?v=sPe5RtUOOdc]

Our flickering LED circuit combined two known circuit, and certainly wasn’t graceful because of it. [sprite_tm] saw quite a few areas where the circuit could be reduced. He ended up taking it down to just two LEDs, a battery, and an ATtiny13. The first step was getting rid of the current limiting resistors. The datasheet shows that with a 3V supply the AVR will limit the current well below the maximum current. The light sensor was removed next. [sprite_tm] referenced an earlier post on sensing with LEDs. He measures the voltage across one of the LEDs while it is off to see how much light is hitting it. The current draw while on is 10mA and 50uA while off.