Developed On Hackaday: Current Status And Selected Beta Testers

June 24, 2014 by Mathieu Stephan 30 Comments

The Hackaday community is currently working on an offline password keeper, aka Mooltipass. The concept behind this product is to minimize the number of ways your passwords can be compromised, while generating and storing long and complex random passwords for the different websites you use daily. The Mooltipass is a standalone device connected through USB and is compatible with all major operating systems on PCs, Macs and Smartphones. More details on the encryption and technical details can be found on our github repository readme or by having look at all the articles we previously published on Hackaday.

As you can see from our commit activity these last weeks have been extremely busy for us. We finally have a firmware that uses all the different libraries that our contributors made but also a chrome plugin and extension that can communicate with our Mooltipass. We’re very happy to say that our system is completely driverless. A video will be published on Hackaday next week showing our current prototype in action as some of the contributors are already using it to store their credentials.

We selected 20 beta testers that will be in charge of providing us with valuable feedback during the final stages of firmware / plugin development. Selection was made based on how many passwords they currently have, which OS they were using but also if they were willing to contribute to the prototype production cost. We expect them to receive their prototypes in less than 2 months as the production funds were wired today.

We think we’ve come a long way since the project was announced last december on Hackaday, thanks to you dear readers. You provided us with valuable feedback and in some cases important github push requests. You’ve been there to make sure that we were designing something that could please most of the (non) tech-savy people out there and we thank you for it. So stay tuned as in a week we will be publishing a video of our first prototype in action!

Want to chat with us? You can join the official Mooltipass Google Group or follow us on Hackaday Projects.

Designing The Second Version Of My Business Card

June 17, 2014 by Mathieu Stephan 12 Comments

At the end of the month my contract with my current employer (no, not Hackaday) will end. With the interviews starting to line up I therefore thought it’d be a nice opportunity to design the PCB business card you can see in the picture above.

It is made of two PCBs soldered together, the bottom one containing the SMD components while the top one only has holes to let most of them pass through. The design was mainly inspired by the first version we already featured on Hackaday although the microcontroller was changed for the (costly) ATMega32u4 and the top PCB was slightly milled so the LEDs may shine through the FR4. The LEDs are connected in groups of 2 (total of 8 groups) to PWM channels and a hidden flash memory allows the card to be recognized as an external 2MB storage using the LUFA library. All source files may be downloaded on my website.

Cypress Launches $5 ARM Dev Board

June 16, 2014 by Eric Evenchick 73 Comments

We do love new development boards at Hackaday, and it’s always nice to see companies providing cheap tools for their products. For those needing a cheap ARM solution, Cypress has just released a PSoC based board that’ll cost you less than $5.

There’s two main ICs on the development board. The first is the target: an ARM Cortex M0+ based PSoC 4 MCU. The second is a CY7C65211 USB bridge. This device is communicates with the target’s built in bootloader for flashing code.

The bridge can also be configured to talk UART, GPIO, I2C or SPI. If you need a USB to serial converter, this part of the board could be worth $5 alone.

The PSoC 4 target happens to be similar to the one our own [Bil Herd] used in his Introduction to PSoC video. If you’re looking to get into PSoC, [Bil] provides a good introduction to what makes these chips unique, and how to get started.

The First Arduino Radar Shield

June 14, 2014 by Gregory L. Charvat 16 Comments

The very first fully operational radar Arduino shield was recently demonstrated at Bay area Maker Faire. It was built by [Daniel] and [David], both undergrads at UC Davis.

Many have talked about doing this, some have even prototyped pieces of it, but these undergrad college students pulled it off. This is the result from Prof. ‘Leo’ Liu’s full-semester senior design course based on the MIT Coffee Can radar short course, which has been going on for 2 years now. Next year this course will have 30 students, showing the world the interest and market-for project based learning.

Check out the high res ranging demo, where a wider band chirp was used to amazing results. Video below.
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Faster Benchmarks With Slower Hardware

June 13, 2014 by Brian Benchoff 22 Comments

hardware

The Bus Pirate is a cheap, simple, Swiss army knife of electronic prototyping, capable of programming FPGAs, and writing to Flash memory. The uISP is possibly the most minimal way of programming Atmel chips over USB, using less than $5 in components. Although the uISP is using a slower chip and bit-banging the USB protocol, it turns out it’s actually faster when operating as a programmer for SPI Flash memories.

Most of [Necromancer]’s work involves flashing routers and the like, and he found the Bus Pirate was far too slow for his liking – he was spending the better part of four minutes to write a 2 MiB SPI Flash. Figuring he couldn’t do much worse, he wrote two firmwares for the uISP to put some data on a Flash chip, one a serial programmer, the other a much more optimized version.

Although the ATMega in the uISP is running at about half the speed as the PIC in the Bus Pirate, [Necromancer] found the optimized firmware takes nearly half the time to write to an 8 MiB Flash chip than the Bus Pirate.

It’s an impressive accomplishment, considering the Bus Pirate has a dedicated USB to serial chip, the uISP is bitbanging its USB connection, and the BP is running with a much faster clock. [Necro] thinks the problem with the Bus Pirate is the fact the bandwidth is capped to 115200 bps, or a maximum throughput of 14 kiB/s. Getting rid of this handicap and optimizing the delay loop makes the cheaper device faster.

Video: The Lowly Diode — Umpteen Functions With Only Two Pins

June 9, 2014 by Bil Herd 28 Comments

The lowly diode, a device with only two leads, can nonetheless do many things. Diodes can detect, rectify, suppress, emit light, detect light, change capacitance, emit microwaves and more. This wide range of use means diodes are included in almost every design and it’s well worth learning more about the inner workings of all kinds of diodes.

My introduction to diodes started like many of my generation with a homemade crystal radio set. My first diode was a piece of pencil graphite in contact with an old fashion safety razor with the joint of the two dissimilar materials — graphite and steel — creating the diode. In this configuration the diode is said to be “detecting” which is the act of turning a weak radio signal into a weak audio signal. At least in my home town of Marion Indiana, one radio station was stronger than the other so that I didn’t have to listen to two stations at once.

Germanium Glass Diode — The venerable 1N34A Germanium Signal Diode.

I eventually learned about “real” diodes and the 1N34A Germanium diode was my “goto” diode into my teens. Nowadays looking into a modern version of the 1N34A you can still see the semblance of the old “cat’s whisker” by looking carefully into the diode.

A quick and somewhat inaccurate semblance of the way a diode works can be demonstrated with marbles and jacks representing negative electrons and positive “holes”. Holes are basically an atom missing an electron due to the combination of elements, a process known as doping. Join me after the break for the explanation.

Demonstrating a PN Junction with marbles and Jacks.

Continue reading “Video: The Lowly Diode — Umpteen Functions With Only Two Pins” →

[Afrotech]’s Guide To Class D Amplifiers

June 9, 2014 by Brian Benchoff 29 Comments

classd

Hang around in any of the many guitar or audiophile forums or discussion boards for long enough, and eventually you’ll come across the arguments over amplifier topologies. One of the more interesting and useful of these classes of amplifier is class d – they’re extremely efficient and when well designed can sound pretty good. [Afrotech] is here to show you how they work, and how to build a 15 Watt amp using a $3 class d amplifier chip.

The very definition of an amplifier is taking a low power signal and transforming it into a high power signal. A great way to modulate a high power signal very quickly is by modulating a square wave with pulse width modulation. A class d amplifier takes a low power input signal, uses it to modulate the duty cycle of a high power square wave, and with a little filtering, amplifies the low power input.

To demo this, [Afrotech] used TI’s TPA3122 class d amplifier chip. It’s a pretty cheap chip for being a 15 Watt stereo amplifier, and the circuit is simple enough to build on a breadboard. With a few caps, resistors, and a pair of inductors, [Afrotech] built this one-chip amplifier that’s capable of powering some pretty big speakers. It’s also very efficient – no heat sink required.

Although class d amps are extremely efficient. there are a few people out there that say because the amplifier is basically a filtered square wave, you’ll be able to hear a difference in the audio over class a or class ab amplifiers. This led to the development of class t amplifiers, basically a class d amp with a higher switching speed (Megahertz for class t, a few hundred kilohertz for class d). Still, if you need a cheap amplifier for a DIY boombox or any other high power application, you could do a lot worse than a simple class d amp.

Continue reading “[Afrotech]’s Guide To Class D Amplifiers” →