[Ranger Bob] crafted this great looking Reverse Geocache box. Our favorite feature is the black piece of acrylic on top. It’s laser cut (not sure if the letters are engraved or not) and gives a great finished look while hiding a couple of things at the same time.

The orange box is a metal cash box, and there’s a smooth indentation in the lid where the handle resides when not being carried. [Bob] removed the handle and mounted the GPS module in that void. But there’s also an OLED display mounted next to it. As you can see in the demo video after the break, the screen is bright enough to be seen clearly through the smoky acrylic covering that depression.

This project gave [Bob] the chance to order his first professionally made circuit board. He did the design in Eagle, managing to keep within the 5cmx5cm limits of Seeed Studio’s least expensive Fusion PCB option. The board hosts the PIC 18F87J50 responsible for handing the screen, GPS module, input button, and USB port. Power comes from an internal Lithium battery.

We’ve featured a lot of Reverse Geocache boxes and they’re still one of our favorite projects because so much love goes into the design and build process. Here’s another one that we chose randomly for your amusement.

The guys over at the 43oh forums have been working on an OLED display booster pack for the TI Launchpad. The booster pack is now available in the 43oh store and is pretty cheap to boot.

The TI Launchpad is an awesome little dev board with a ravenous fan base. We’ve seen a lot of projects on Hack a Day use a Launchpad – everything from intervalometers to chicken coops. Unfortunately, the MSP430 doesn’t have the market penetration of the ‘board that shall remained unnamed,’ so it’s not very common to see a new Launchpad “shield.”

[bluehash] on the 43oh forums has been hard at work for the past month to put together his OLED booster pack. The display is 128×64 pixels with an incredible amount of brightness that we would expect from an OLED display. The software for the display is based on the SSD1306 driver with two font packs – Courier New large and small. Not a bad little piece of kit for an under appreciated dev board.

If you’re not already familiar with the 4D Systems µOLED-128-G1 display, [Gary] put together a project that shows some of the features it offers. This is a smart display, having its own onboard microcontroller and a microSD slot. The SD card stores image and video data, while the microcontroller takes care of displaying them based on simple serial commands it receives. This means you can hook it up to a computer or microcontroller and show still or animated sequences with minimal programming effort. We’ve embedded a video after the break, or you can look in on this slot machine project from last year that used the same module.

[Gary] is using a PIC microcontroller programmed with PIC Basic Pro. But most of the work is done with a 4D Systems program called Graphics Composer. You build out the images and animations you want to see on the screen, which are then formatted for the display and written to the SD card. [Gary] mentions that the card is not written using a traditional filesystem, so if you know of another way to write data to and from this card we’d love to hear about it in the comments. The image editing software will also spit out the serial commands necessary to pull your freshly minted graphics up on the display.

Is there a place in the dashboard of your high performance automobile for this Engine Control Unit feedback panel? There’s several methods of showing information at work here. The row of LEDs at the top of the bezel provide RPM feedback. The two red LEDs with chrome bezels are alarm indicators. But that big OLED display is the centerpiece of the unit. Not only can you scroll through a myriad of display options, but the screen packs more than enough contrast to be readable during the day. It looks like [Mathieu] is selling these units and has decided not to release source code because of this, but there’s a schematic available and a video after the break shows the menu system from which you can draw inspiration.

If you’ve ever thought of utilizing a small and inexpensive OLED display in your project [Rossum] has the details you need to get started. In the past we’ve seen him take a tour of available LCD screens and this is much the same, detailing his look at three different models. In the video after the break each is connected to a driver board that he made. The boards have two important components, the first is a boost driver for the 12-16V input the screens need, the second is an octal buffer necessary if you are using a 5V microcontroller. These take care of the hardware considerations, making it simple to drive them with a chip of your choosing.

[Jeri Ellsworth] has put together a couple of videos that cover how she made her own organic light emitting diodes, or OLEDs. In the first video, after the break, it discusses the difference between regular, rigid semiconductor LEDs and organic LEDs. The video then goes on to show how to make an OLED as successive layers of materials. Indium tin oxide (ITO) on glass forms a transparent anode. That is then coated with PEDOT:PSS, a conductive polymer mix that is used as a hole transport layer. Then a red diamond ruthenium complex is added to create the emissive layer. The cathode layer is a low work function metal, initially, gallium indium eutectic alloy then later other metals were shown to work. The second video, shows how to juice a glowstick and make OLEDs with the liquid. The dye in blue glowsticks, 9,10-Diphenylanthracene, is an organic semiconductor and will emit light as an electric current is passed through it. The glow stick method seems to have some problems as the ITO coated glass plate is degraded by the glowstick chemicals. It would be interesting to see if using the porous aluminum or similar technique from [Jeri]‘s flexible electroluminescent displays could be used as an electrode.

Here’s an interesting take on augmenting a car’s dashboard. [Daniel] is using a button blank to house a 1″ OLED display in his Jetta. It shows auxiliary data such as boost pressure and several sets of temperature readings. The display itself has a tiny little circuit board with a PIC 24 to drive it. A larger board, seen above, collects the temperature data from some sensors that [Daniel] added as part of the hack. There are some pictures of the installed display inside of the dark car and it looks really easy to read. It also sounds like there’s some dimming functionality built into the firmware. This is the easiest way we’ve seen to add a display to your dashboard as it just requires you to pop out a button blank, rather than disassembling the entire console or patching into what’s already there.

We have gotten a number of Arduino tips in the last couple days, and we thought we would combine them for your convenience. The first tip we received was for some hints provided by [Bill] on some digitalWrite() alternatives. Similar to some previous research we covered, this tip also includes some tips on how to make the direct register writing a little easier by using #define to simplify things. Obviously this wont be as idiot-proof as digitalWrite() is, but we think you can handle it.

Our second tip is for a set of OLED displays from 4dsystems sold as Arduino Shields. They have a couple of different sizes from .96″ to 1.7″, depending on your needs and budget. There is no official display library for them yet, but 4dsystems have been kind enough to provide a few resources to work from. Hopefully we’ll see a few great applications from this, maybe a much bigger pixel Mario? A much smaller Game of Life? Feel free to send us your projects, or leave your ideas in the comments!

Want to really stretch the battery life on your phone? If you have an OLED display [Jeff Sharkey] may have the answer. He did some testing with his Nexus One to see if color alterations can save on current. Darker colors draw less amperage and he found that the red pixels are the most efficient. He did a little work with SurfaceFlinger, which handles the display on Android devices to make this easy, but what will you get by going red? He measured that using only the red pixels dropped the current use down to 35% of what the full color display was pulling. This reminds us of those efforts to save energy by running a black background with Google. Whether you use it or not his post is an interesting read.

There’s nothing groundbreaking about this hack, called the TweetWall, but the craftsmanship is gorgeous! [Yergacheffe] had access to the right tools; an epilog laser and a thermoplastic bender (an item we didn’t know we needed until now… thanks a lot). It has the usual bits you’d expect in a Twitter ticker, an LED matrix and an Arduino. There is also an OLED screen that displays the avatar of the current Twitter feed. Because data is transferred over a serial connection the SD slot on that screen is used to cache images which helps to keeps the messages coming without delay. The end product is quite good, we’d expect to see it hanging on the wall of the pub down the street.

The University of Wisconsin is hosting a tutorial on how to make your own Organic Light Emitting Diodes. This is so amazingly awesome. We want you guys to make some. Someone make your own matrix and display some patterns on it and submit it. Please. Though we’ve seen lots of uses for OLED screens, we never really delved into the process of creating them. It looks much less complicated than we would have imagined.

[via MakeZine]

The fantastic people at MIT have taken it upon themselves to explain how an OLED works. Their visual aide in this explanation is an electrocuted pickle. This helps describe how OLEDs are actually constructed from organic material.  Many of you probably already know how they work, but for those who don’t this video will clear up any questions you might have. Even if you do know how OLEDs work, you may learn something too. We hadn’t realized how amazingly thin the displays are.

[via Engadget]

We caught a glimpse of this Basic Stamp 2 controlled electronic slot machine on YouTube. We’re very grateful that [Mike Donahue] was willing to share more about his project with us.

He uses tactile switches instead of dropping coins in a slot, and a lever-style switch sets the one-armed bandit in motion. The action is displayed on a 1.5″ µOLED-128-G1 screen that has its own controller (which explains how this operates so well with the relatively slow BS2). For realism there’s some pretty good sound effects provided by a piezo speaker. We’ll look at the code, graphics, and some video after the break.

The connections are quite simple and [Mike] has built the project on the Basic Stamp 2 Homework Board. The display is addressed through two serial lines and a reset pin.

He generated the graphics using MSpaint, creating three full screen images that rarely change. The icons for the spinning dials are much smaller and overlayed on top of the larger images. Three of these icons are stored next to each other in memory. That way, a pointer can be advanced and the next image will start to scroll in, resembling a spinning cylinder. Here’s a bit larger version of the schematic and images if you need it.

This makes for a fun toy and it’s quite well executed. If you’re interested in taking a look under the hood, here’s a copy of the source code.

[John] wanted to take a pong clock and put it in a wristwatch form factor. Take an afternoon and pour over his detailed build logs. This multi-year project is done with meticulous cleanliness that makes us jealous. He’s milled the case and buttons himself, achieving a professional look that equals or surpasses the quality of some commercially available “gaming” watches. The project centers around an OLED display driven by a TI MSP430F2013 processor. Don’t miss the video after the break covering prototyping, PCB work, case milling, and the watch in action. Currently, this is the third generation of development but with a project this exciting, are you ever really finished?

[Thanks Chris]