The LED display toy known as the Peggy2.0 just keeps getting cooler and cooler. [Leonard] is now sharing with us how we can stream flash animations to one. It requires some Java and an Arduino, but the final effect is quite fluid and responsive. We’ve seen the Peggy grow from basically an electronic litebright to doing video and even being chained together to make larger displays.
Since we first mentioned the Leapfrog DIDJ, a lot has happened. A number of avid readers of Hack a Day teamed up with a couple hackers experienced with the DIDJ, and have managed to make some huge progress into making a linux based game console on the cheap. For all the readers who missed out on the last sale on Woot, its about time for a second chance.
The team working over at the HackerFoundry forum have managed to gain serial console access, map the file system, create a fake update server, and are almost at a point where replacing the stock OS and firmware can be done with software alone. They have also designed and tested a homebrew cartridge with a slot for a microSD card and breakouts for expansion and debugging.
Right now they are looking for someone with experience snooping USB protocols to figure out how the device communicates to the computer, as well as anyone who is interesting in just testing or playing around with what they have done so far. There are a number of tutorials and walk-throughs on the eLinux wiki. Its amazing how far this group has come in just two months.
[Vsergeev] built an echo pedal for a guitar or with other audio manipulation applications. He used an mbed microcontroller for the project. You may remember Hackaday writer [Phil] labeling the mbed an ‘Arduino on steroids’, and it certainly handles this audio processing quite well. We’ve included a clip of the echo effect after the break. During the design process, [Vsergeev] used LTspice to simulate the analog circuitry and make things right before committing to the physical circuits.
Continue reading “Guitar echo pedal built with mbed”
Cardboard record player
[Yen] tipped us off about this cardboard record player. It’s a marketing tool that you receive in the mail. Inside the cardboard packaging is a record and the packaging itself can be folded into a player.
The NanoNote is a tiny handheld housing a lot of power for a small price. It ships running openWRT and sports a full keyboard, 336MHz processor, 32 MB ram, and 2 GB of flash memory. Not bad for $99. [Thanks Drone via Linux Devices]
Virtual page flipping physical interface
Love reading ebooks but miss flipping through the pages? [Marcin Szewczyk] developed this interface that lets you flip a couple of sheets of plastic to turn and fan through pages on the screen.
Augmented reality tat
Not interested in supporting an ink artist or just can’t decide on the design? Perhaps you should get an augmented reality marker tattooed on your arm and have the art digitally added for those who have already made the switch away from using their analog-only eyes. [Thanks DETN8R via Asylum]
Cooking with a CPU
[Bo3bo3] is practicing the art of cooking with processors but he’s bumped things up a notch. Instead of cooking inside a computer case, he removed the processor from the board and made it USB powered. [Thanks Waseem]
[Dmritard96] built this automated watering system to keep his garden growing while he’s out-of-town. It uses rain barrels, which capture and store rainwater, as a source. These barrels provide very low water pressure so he’s added a battery-powered pump along with a solar array for recharging. Don’t worry, if the rain barrels run dry there’s a float sensor that will switch the system over to city water and stave off those wilted leaves.
Here’s an interesting idea: replace a disposable coin cell battery with a capacitor in order to filter the noise from an external power supply. [David Cook] is taking advantage of the falling costs of digital calipers. He’s mounted one on his milling machine but noticed that with an external power supply the readings would sometimes reset in the middle of his work. The LR44 cell he’s replacing makes for very difficult in-place soldering so instead of permanently replacing it he built an insert that matched the form factor. The outer ring is from a piece of copper tubing and soldered to a PCB that he etched.
If [David's] name sounds familiar it’s because we featured his Happy Meal toy scavenging a while back.
We see it all the time, a post based on an Arduino board with multiple comments calling it overkill. How exactly should you control your homemade peripherals if you’re not using a microcontroller (uC)? [JKAbrams] and [Tim Gremalm] answered that question with this printer port (LPT) adapter. They wanted an indicator light when someone in an IRC room was talking to them. By connecting a blue rotating light through a relay to the output of this fob they’ve done just that, but there’s room for much more.
The adapter uses a Darlington transistor array IC to protect the computer. A resistor between the LPT and the base pin on the chip ensures that current flow will be well within the safe levels for the computer. The Darlington transistor amplifies the output using an external power supply in order to drive heavier loads.
If you want a deeper understanding of the printer port check out this tutorial. LPT ports are becoming less common and that’s why so many projects are migrating over to USB (plus there’s no need for external power with most USB connected projects) but if you’ve got one, it’s probably not being used for anything else.