[Greg] is really working on a small scale with his LED Matrix backpack PCB. It’s a toy that he designed as an activity. He constrained himself to a board which would exactly match the outline of an 8×8 bicolor LED matrix package.

What you see here is the side of the PCB which will be facing the underside of the LED dot matrix module. Let’s call this the top of the board. The underside has a CR2032 battery holder which provides enough juice to run the display. Since the matrix is bi-color there’s a slew of pins to drive. [Greg] uses three shift registers for the high side, and sixteen N-channel MOSFETS for the low side. He’s chosen an MSP430G2201 microcontroller which has a nice sleep mode for power conservation. It has no problem driving tri-color animations as seen the clip after the break, but also has an unpopulated clock crystal footprint if you wanted to use it as a timepiece.

Despite the small footprints and cramped board [Greg] still hand soldered all of the components. He even posted a time-lapse of the process in the page linked at the top.

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[Bill Porter] is helping a friend out by designing a simple security system for her home. It relies on Xbee modules to alert a base station when doors are opened, or a pressure mat is stepped on.

The door sensors are quite simple, and you’re probably already familiar with them. One part mounts to the door and has a magnet in it, the mating part mounts to the jamb and has a reed switch that closes a contact when the magnet is in place. The floor mat uses two sheets of conductive material separated by bits of foam. When it is stepped on a circuit is completed and can be sensed by the Xbee as a button press.

These sensors report back to an Arduino base station that has a buzzer and three 8×8 LED modules to scroll a message saying which sensor was tripped. [Bill] does a good job of showing what goes into configuring an Xbee network if you’ve never worked with the hardware before.

You’ll find his demo video after the break.

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[Retro Brad] has come a long way with his 8×8 gaming device which he calls Super Pixel Bros. The newest rendition has a fab house PCB and freshly rewritten code. The game is still played on an 8×8 LED matrix, but it looks like he’s sourced a version with square pixels, which is a nice touch since he was inspired by the block-based Super Mario games. Also new in this version is the character LCD screen which displays score, level, and life information. But it’s not just the shiny new hardware that’s different, he’s rewritten the software in Swordfish Basic to run on the PIC 18F4550. The new code allowed him to tweak how levels are loaded and stored. He’s even written a level editor and has finished 20 levels thus far.

The demo after the break does a great job of showing off the hardware and the game play. He’s added a lot, including enemies, the ability to shoot fire, and of course the common moves of jumping and breaking blocks is all there. He mentioned that the fab house he used is selling boards for around $5 and he’s looking into the possibility of getting a kit service up and running.

His progress since we last checked in on the project is quite impressive.

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[Daniel] wanted his child to stay in bed until a semi-decent time each morning. The problem is the kid doesn’t know how to read a clock, so [Daniel] built him a clock. Yeah, doesn’t make much sense to us either, but we’ve used our own shaky premises for projects so who are we do judge?

He used a bi-color 8×8 LED matrix as the clock display. What caught our eye is the point-to-point soldering he used for the three strip boards that make up the device. Note the use of a drill-bit to break the traces when needed. Each board has its own purpose; the matrix drive, the logic board, and the power board. A PIC 18F4550 lets [Daniel] control the clock via USB, and takes care of lighting up the hour as a red number when it’s time to sleep, and a green one when it’s okay to arise. There’s a flashing pixel for seconds, and a binary readout of minutes along the bottom.

We’ve asked [Daniel] to post a schematic and an image of the clock face when displaying the time. No word yet but we’ll keep our eye on it. In the mean-time, check out this clock that uses an RGB 8×8 LED matrix.

A lot of thought went into [Patrick Mccabe's] Pong gaming console build. He used components we’re familiar with; an Arduino as a controller, 8×8 LED modules as the display, and potentiometers (with fancy knobs) in project boxes as the controllers. But every step along the way he took care to build this cleanly and robustly. Even the MAX7219CNG drivers for the six LED modules reside on PCBs from a fab house. The finished project is something you’d be proud to pull out and play when you have friends over. Even if they’re not part of the geek elite we think they’d enjoy a game or two. Great job [Patrick]. We hope to see an internalized microcontroller and scoring in your next update!

Want to do this but the cost of the matrix drivers scared you away? Follow our tutorial to build your own display using an AVR for the multiplexing.

This little board serves as a current gear indicator for a motorcycle. It was designed with the Suzuki V-Storm motorcycles in mind as they have a sensor built into the gearbox. Other gear indicators rely on sensors on the shifters themselves, but reading the voltage level from a gearbox sensor gives much more reliable information.

The voltage measurement is handled by an ATmega88 microcontroller which in turn drives the 8×8 LED display. Also built into the system is a temperature sensor and photoresistor. The firmware takes advantage of both of these inputs, displaying temperature when in sixth gear or at the push of a button, and dimming the display based on ambient light. There are also settings for screen rotation, and user preferences.

We didn’t find schematics or software but this should be pretty easy to replicate. If you need a primer for AVR programming we’ve got you covered.

[Thanks Michal]

[Mathieu] built this display in hopes that he can play pong on it. You can imagine the headache that awaits when trying to figure out how to drive the 6144 bi-color LEDs. I must have worked out because the thing looks great in the video after the break. The solution he chose was a bit unfamiliar to us though. He used a Field Programmable System Level Integrated Circuit produced by Atmel, or FPSLIC. This is a kind of mash-up of components we’re more accustomed to.

The AT94K is a single chip that houses an 8-bit AVR microcontroller, and FPGA, and SRAM. This project uses that FPGA to handle the multiplexing of the display via code written in VHDL. The AVR core receives data via a USB port, stores two images in the SRAM (one for each LED color), and then outputs it to be drawn on the display. On second thought, this project sounds like fun and it’s a great way to get start learning that VHDL you’ve been putting off. Read the rest of this entry »

The GLIP project takes the delight of blinking LEDs and combines it with the ingenuity of modular communications. This takes the Puzzlemation concept a few steps further. In that project the modules were programmed through a base station and could be removed and used as a puzzle from there. The GLIP project uses a master block that you can see tethered in the photo. But the blocks communicate with each other via an infrared protocol. This way they can be continuously updated as they are place next to each other. Each module includes an STM32F105 ARM Cortex-M3 processor, quite a punch for the little blocks. Take a look at what they can do after the break.

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