Day: September 19, 2013

Advanced Transcend WiFi SD Hacking: Custom Kernels, X, And Firefox

September 19, 2013 by 95 Comments

[Dmitry] read about hacking the Transcend WiFi cards, and decided to give it a try himself.   We already covered [Pablo’s] work with the Transcend card. [Dmitry] took a different enough approach to warrant a second look.

Rather than work from the web interface and user scripts down, [Dmitry] decided to start from Transcend’s GPL package and work his way up. Unfortunately, he found that the package was woefully incomplete – putting the card firmly into the “violates GPL” category. Undaunted, [Dmitry] fired off some emails to the support staff and soldiered on.

It turns out the card uses u-boot to expand the kernel and basic file system into a ramdisk. Unfortunately the size is limited to 3MB. The limit is hard-coded into u-boot, the sources of which transcend didn’t include in the GPL package.

[Dmitry] was able to create his own binary image within the 3MB limit and load it on the card. He discovered a few very interesting (and scary) things. The flash file system must be formatted FAT32, or the controller will become very upset. The 16 (or 32)GB of flash is also mounted read/write to TWO operating systems. Linux on the SD card, and whatever host system the card happens to be plugged in to. This is dangerous to say the least. Any write to the flash could cause a collision leading to lost data – or even a completely corrupt file system. Continue reading “Advanced Transcend WiFi SD Hacking: Custom Kernels, X, And Firefox” →

Desoldering Chips With Fire

September 19, 2013 by 29 Comments

Salvaging components is a staple of any electronic enthusiast, but many times those interesting chips – old 8-bit microcontrollers, memories, and CPUs found in everything from game consoles to old computers – are rather difficult to remove from a board. [Ryan] over on Instructables has a rather interesting method of removing old SMD packages using nothing more than a little fire and a pair of tweezers.

Obviously the best way to go about salvaging SMD components is with a heat gun, but lacking the requisite equipment, [Ryan] managed to remove a few SMD chips using rubbing alcohol as a heat source. In a properly controlled environment, [Ryan] filled a small metal dish with alcohol, set it on fire, and used the heat generated to remove a few components. Alcohol lamps are a common bench tool in a range of repair disciplines because the fuel is cheap and burns relatively cleanly (not leaving an unwanted residue on the thing you’re heating).

It’s an interesting kludge, and given [Ryan]’s display of desoldered components, we’re going to call it a success. It might also work for through-hole components, allowing for easy removal of old SRAM, ROM, and other awesome chips.

BeagleBone Black Does CNC With RAMPS

September 19, 2013 by 13 Comments

[Bart] Wanted to try controlling a CNC with his BeagleBone black, but didn’t want to invest in a CNC Cape. No problem – he created his own translator board for RAMPS. LinuxCNC for the BeagleBone Black has been available for a few months now, and [Bart] wanted to give it a try. He started experimenting with a single stepper motor and driver.  By the time he hooked up step, direction, and motor phases, [Bart] knew he needed a better solution.

Several CNC capes are available for the BeagleBone boards, but [Bart] had a RAMPS board just sitting around, waiting for a new project.  Most RepRap fans have heard of the RAMPS – or Reprap Arduino Mega Pololu Shield.  In fact, we covered them here just a few days ago as part of our 3D Printering series.   RAMPS handle all the I/O needed for 3D printing, which carries over quite nicely to other CNC applications as well.   The downside is that they’re specifically designed for the Arduino Mega series. Continue reading “BeagleBone Black Does CNC With RAMPS” →

Fail Of The Week: Smoking Pulse Sensor And BLE Disappointment

September 19, 2013 by 12 Comments

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We think [Thomas Brittain] is onto something. We often post to our personal blogs so that we have a reference to how we did something. But he also keeps a long post that documents his abandoned projects. It ends up serving as a quick start if he ever decides to pick up the torch once again. Lucky for us he’s included his failures in the write up. This Fail of the Week features the top two posts on his Incomplete Works page. The first is an attempt to make his own pulse sensor. The second is a miserable experience with a cheap Bluetooth Low Energy module.

Continue reading “Fail Of The Week: Smoking Pulse Sensor And BLE Disappointment” →

A Spinning Beachball Of Doom That You Can Carry In Your Pocket

September 19, 2013 by 11 Comments

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Need a way to tell the world that you’re mentally ‘out to lunch’? Or what about a subtle hint to others that your current thought process is more important than whatever they are saying? [Caleb Kraft] — who earlier this year bid farewell to Hackaday for a position with EETimes — is heading to the World Maker Faire in New York this weekend, and he decided to build just that device. If you’re heading to Maker Faire too, keep an eye out for his eye-catching Spinning Beachball of Doom. He was inspired by iCufflinks from Adafruit, and ended up with a great little device that is small enough to be worn, or just thrown around for fun.

A couple of weeks ago, we linked you to the Adafruit announcement of their new Trinket product line. [Caleb] wasted no time in finding a use for the tiny microcontroller board. He paired it with the Neopixel LED ring, and had it working with just a tiny tweak to the test code. He then used DesignSpark Mechanical to design a 3D-printed case… the most complicated part of the project. It’s too bad his original plan to power the whole thing with button cells didn’t work out, because it could have been a neat (albeit expensive) upgrade to LED throwies. That said, [Caleb] mentions that a small LiPo battery would be a good alternative.

This is a fun little project that most anyone could throw together in an afternoon. Don’t be surprised if we start seeing these show up more and more.

To see what it looks like in action, check out the video after the break.

Continue reading “A Spinning Beachball Of Doom That You Can Carry In Your Pocket” →

FLASH.IT: The RGB LED Climbing Wall

September 19, 2013 by 11 Comments

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[Chris] and his friends were kicking around ideas for a Burning Man project, and this is the one that stuck: a rock climbing wall with RGB LEDs embedded in the holds. The holds themselves were custom made; the group started by making silicone molds of varying shapes and sizes, then added the electronics and poured in polyurethane resin to create the casting. The boards for these LEDs are equipped with a central hole that pairs up with a peg in the silicone mold. [Chris] also solved an annoying spinning problem by affixing a bolt to the far end of the LED board: once embedded in the polyurethane, the bolt provides resistance that the thin board cannot. The finished holds bolt onto the wall with all their wires neatly sticking out of the back to be hooked up to a central controller.

The Instrucables page suggests a few ways to get the lights working, including grabbing the nearest Arduino and relying on the Neopixel Library from Adafruit. [Chris] went the extra mile for Burning Man, however, designing Arduino-software-compatible controller boards capable of communicating via DMX, which expanded the system from a simple display to one capable of more complex lighting control. Stop by the Github for schematics and PCB layouts, and stick around for a video of the wall after the break. If the thrill-seeking outdoorsman inside you yearns for more, check out WALL-O-TRON from earlier this summer.

Continue reading “FLASH.IT: The RGB LED Climbing Wall” →

Accurate Temperature Control Of Your 3D Printer Extruder

September 19, 2013 by 16 Comments

[Tim] is working on building a 3D printer and using it as an excuse to learn as much as he can. The first big issue he tackled was accurate temperature control, so he made an interesting write-up on how to characterize the thermal properties of an QU-BD extruder’s hot end and use that information to create a control algorithm for the heater.

The article starts with a basic thermal model and its corresponding formula. [Tim] then runs several tests where he measures the heater and extruder tip temperatures while switching on and off the heater. This allows him to figure out the several model parameters required to design his control algorithm. Finally, he tweaked his formula in order to predict the short term future so he can know when he should activate the heating element. As a result, his temperature is now accurately controlled in the 200°c +/-1°c window that he was shooting for.