Syncing Two Strands Of G35 Christmas Lights

December 4, 2012 by Brian Benchoff 6 Comments

Lights

For a few years now, the set of Christmas lights most wanted by hackers and makers the world over is the GE G35 color changing set. With 50 individual RGB LEDs controlled by a microcontroller, these light strings can display any pattern of lights with the help of something as simple as an Arduino. The stock light sequences are a little problematic, especially if you’re running more than one string.

[Todd] picked up two G35 strings, and even when they’re turned on at the same time the light sequences slowly go out of sync after a half hour or so. He came up with a great way to make sure these lights stay in sync that requires only a slight modification. To make two light strings stay in sync, it’s simply a matter of disconnecting the data line from one string’s controllers and bridging that connection with the other string.

It’s a very easy modification, but it won’t give you twice as many individually controllable LEDs – for that, you’ll have to use either multiple Arduinos or buy a longer RGB LED strip. Still, having two identical 7×7 LED panels is better than a single panel, so we’ll have to tip our hat to [Todd] for this one.

MonoPong: A CMOS 1-D Pong

November 23, 2012 by Eric Evenchick 6 Comments

We’ve seen a few 1-D pong games recently, and they’ve all be controlled using microcontrollers. Inspired by some of these hacks, [mischka] built the monoPong using a handful of logic chips.

The monoPong has four major components. A 555 timer in astable mode provides a clock source which is fed into a 4510 decade counter, which connects to a 4028 BCD to decimal decoder to drive the LEDs. Finally, a 4011 NAND gate IC is used to deal with the button presses. Two of the NAND gates form a RS flip-flop, and the other two NAND each player’s button with the last LED on the player’s side of the strip. If the player hits the button when their LED is on, the RS flip-flop toggles and changes the decade counter from count up to count down mode. This makes the ball bounce back.

[mischka] finished the project off by putting it in a wooden box and drilling holes for the LEDs, buttons, and a power switch. The final product looks pretty good, and is a great example of how you can use a couple logic chips instead of a microcontroller.

After the break, watch a quick game of monoPong.

Continue reading “MonoPong: A CMOS 1-D Pong” →

8x8x8 LED Cube And The Board That Drives It

November 22, 2012 by Mike Szczys 14 Comments

Check out the LED cube which [Thomas], [Max], and [Felix] put together. But don’t forget to look at that beautiful PCB which drives it… nice! But hardware is only part of what goes into a project like this one. After the soldering iron had cooled they kept going and wrote their own software to generate patterns for the three-dimensional display.

Looking at a clean build like this one doesn’t drive home the amount of connections one has to make to get everything running. To appreciate it you should take a look at this other 512 LED cube which has its wires showing. You can see from the schematic (available in the project repository) that all of these lines are managed by a series of shift registers. The board itself connects to a computer from which it gets the visualization commands. A Java program they call CubeControl can push letters or turn the cube into a VU meter.

The team built at least two of these. This smaller version uses red LEDs, while the larger one shown in the video after the break has blue ones.

Continue reading “8x8x8 LED Cube And The Board That Drives It” →

One Dimensional PONG, Take Two

November 18, 2012 by Brian Benchoff 22 Comments

Needing a Christmas present for his 4- and 5-year-old nieces, [John] built a one-dimensional PONG game, sure to be the delight of rosy-cheeked children on a Christmas morn.

The new and improved 1D PONG game is built around a digital RGB LED strip with an LPD8806 LED controller. The speed of the ‘ball’ is controlled by a pot on one side of the game. With each player pressing their button at the right time, the ball bounces back to the other player. Missing the ball awards a point to the other team and most likely an increase in the player’s frustration, greatly increasing the risk of this game being thrown across the room.

While it’s not an obscenely long 1D PONG game like [Jason]’s previous 5 meter version, it’s more than enough to keep a pair of kids occupied for more than a few minutes, a remarkable achievement for just a microcontroller, buttons, and a piece of LED strip.

You can get [John]’s AVR code in this pastebin or just check out the video after the break.

Continue reading “One Dimensional PONG, Take Two” →

POV Wheels For A Longboard

November 16, 2012 by Mike Szczys 9 Comments

If you don’t mind working with really small components this POV wheel project for a longboard will certainly attract some attention.

The name of the game here is small and cheap. Small because the wheels are only 72mm in diameter (about 2.8 inches). Cheap because [Ch00f] wants to produce and sell them locally. He went with an ATtiny24 microcontroller driving fifteen LEDs. Obviously this will present a problem as the uC uses a 14-pin SOIC package and that’s just not enough I/O to drive the LEDs individually. Add to that the issue of storing patterns to be displayed and you start to run out of program memory very quickly.

But obvious he pulled it off. The image above shows the wheel displaying the CT logo (for ch00ftech.com) and there are several other patterns shown off in the clip after the break. The LEDs are multiplexed, but the wheel spins fast enough that this turns out to be okay. The rotation is measured by an IR reflectance sensor aimed at the stationary axle. A CR2032 powers the device, with some counterweights added to keep the wheel balanced.

Our only concern is the fragility of the exposed electronics. But if you hit the right BOM price we guess you can just replace the board as needed.

Continue reading “POV Wheels For A Longboard” →

Roomba And Virtual Walls Make Up This Theme Family Halloween Costume

November 15, 2012 by Mike Szczys 7 Comments

It figures. You spend a ton of time making a cool set of costumes and then you can’t get your kid to pose for a picture. It’s okay though, we still get the point. This themed set of costumes dresses the little one as a Roomba vacuuming robot while mom and dad are suited up as virtual walls (modules that are used to keep the bot from falling down stairs, etc.). It’s fun and unique, but had it not been for some additional electronics this would have been relegated to a links post. For safety sake each costume was outfitted with a ring of LEDs. As a challenge, the lights were given the ability to sync up patterns with each other.

Each costume has a circular frame at the top with a set of RGB LED strings attached. To get them to display synchronized patterns an IR transmitter/receiver board was designed and ordered from OSHPark. Each costume has four of these modules so no matter where the wearers are facing it should not break communications. A demo of the synchronized light rings can be seen after the break

Continue reading “Roomba And Virtual Walls Make Up This Theme Family Halloween Costume” →

Birthday Badges Teach Kids How To Solder

November 12, 2012 by Mike Szczys 15 Comments

[Ian Lee, Sr] wanted to have an educational activity at his younger son’s birthday party. These were uncharted waters for him as he doesn’t remember education taking place at his own early birthday parties. But he came up with a great idea, with was to teach soldering using interactive badges which each guest could assemble themselves. He needed about twenty, so he tried to keep the BOM as small as possible. But that didn’t mean skimping on features.

You can see the black LED-type package on the left of the assembled badge above. This is an IR receiver whose counterpart transmitter is on the right side of the board. When two of these get within 6-8″ of each other the start talking back and forth. There is no microcontroller involved, instead the system relies on a multivibrator design. One of the red LEDs at the corner of the ‘smile’ is always blinking. When it is off, the IR transmitter is powered. This is picked up by another badge’s receiver, which lights the second ‘smile’ LED. You can see this happen in the short clip after the break.

Although there are relatively few components that went into this, it would take the kids a long time to put them together as they’re just learning. [Ian] and his eldest son soldered on all of the components except for the resistors beforehand.

Continue reading “Birthday Badges Teach Kids How To Solder” →