The Worst E-Reader Ever

June 14, 2014 by 29 Comments

oled

Over on the Projects site, [Jaromir] has created a tiny device with an OLED display, three buttons, and a USB port for storing text files, be it for saving a shopping list, a cheat sheet, or the most unusable e-reader ever made.

The front of the device is simply a 96×32 pixel OLED and three buttons for ‘up’, ‘down’, and ‘open/close’. The reverse side is where the magic happens with a PIC24 microcontroller that sets up a file system on the chip, allowing [Jaromir] to write 64kB of data on what is actually a Flash drive with a pitiful capacity. Text files are viewable on the OLED, with the video below showing the front page of Wikipedia being displayed in a glorious 16×4 text mode.

It’s not a very useful device by any means, but for some reason it’s garnered a lot of skulls and followers over on Hackaday Projects. In response to that, [Jaromir] is working on version two with a new PCB and a design for a 3D printed case. Not bad for what [Jaromir] himself describes as worse than just about any phone or tablet.

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The first Radar Arduino Shield

The First Arduino Radar Shield

June 14, 2014 by 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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Home Made Miter Saw Is Not Completely Dangerous

June 14, 2014 by 43 Comments

Home Made Miter Saw

If the term ‘home made miter saw’ instantly instills frightening images of severed limbs into your head, you’re not alone. A quick internet search will yield some pretty hokey tool builds, we’ve even featured a few here on hackaday. This saw is different. [Pekka] made a pretty cool saw for cutting very accurate angles in wood.

This saw was purpose built with one goal in mind: cutting wood that will be glued together for use in segmented turning. Segmented turning is shaping a piece of wood stock that is composed of many different types of wood. This results in a very visually interesting product.

Home Made Miter SawMost of the saw is made from plywood. The hinge and supports for the arbor are beefy off-the-shelf pillow blocks. A 3-phase motor with speed control transmits power to the arbor via a belt. Belt tension is adjusted by sliding the motor further back along the motor mount base. [Pekka] took care so that the entire pivoting assembly was nearly balanced adding to the ease of use.Typical miter saws rotate the blade to achieve different angles of cuts. This design rotates the saw fence.

For safety there are a pair of polycarbonate blade guards and a micro switch on the handle that won’t let the saw start unless it is depressed. The micro switch has a secondary function also, when let go it applies an electronic brake to the motor so that the spinning blade does not touch the work piece when lifting the blade back up.

An ARM-Based DSP Modelling Synth

June 14, 2014 by 42 Comments

synth

The great analog synths of Moog, Oberheim, Sequential Circuits, and more modern version from Doepfer are renouned for their sound, the sheer majesty of a rack full of knobs and plugs, and of course the price. Analog synths are simply expensive to build, and given that aficionados even scoff at digitally controlled oscillators, require a lot of engineering to build. [Jan]’s DSP-G1 isn’t like those analog synths – it uses microcontrollers and DSP to generate its bleeps and boops. It is, however, extremely cheap and sounds close enough to the real thing that it could easily find a home between a few euroracks and CV keyboards.

plugThe heart of the DSP-G1 is a micro from NXP modeling an analog synthesizer with 15 digitally controlled oscillators with Sine, Triangle, Pulse and Saw outputs, a low frequency oscillator, two envelope filters, and a low pass filter, or about the same accouterments you would find in a MiniMoog or other vintage synth from the 70s. Since this is basically a synth on an NXP LPC-810, [Jan] has packaged it in something akin to a MIDI to 3.5mm cable adapter: Plug a MIDI keyboard into one end, an amp into the other, and you have a synth smaller than the MIDI Vampire, an already impossibly small music creation tool.

[Jan] has a few more versions of his little DSP device with varying amounts of knobs available on his indiegogo campaign. The DSP-Gplug is the star of the show, though, provided you already have a MIDI keyboard with a few knobs for the required CC messages. Videos and sound demos below.

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Do You Have Any Idea How Fast Your Blender Was Going?

June 13, 2014 by 23 Comments

blenderSpeed Some people really love their smoothies. We mean really, really, love smoothies and everything about making them, especially the blenders. [Adam] is a big fan of blenders, and wanted to verify that his Vitamix blenders ran as fast as the manufacturer claimed. So he built not one, but two speed measuring setups. Scientific blender measurement method requires one to cross check their results to be sure, right?

Measuring the speed of a blender is all about the RPM. Appropriately, [Adam’s] first measurement tool was an LED based stroboscope. Stroboscopes have been around for hundreds of years, and are a great way to measure how fast an object is rotating. Just adjust the speed of a flashing light until the rotating object appears frozen. The number of blinks per second is then equal to the Rotations Per Second (RPS) of the object being measured.Multiply by 60 seconds, and you’ve got RPM. [Adam] used an Arduino as the brains behind his stroboscope. He wired a dial up on his breadboard, and used it to adjust the flash rate of an LED. Since this was a quick hack, [Adam] skipped the display and just used the Arduino’s USB output to display speed measurements on his laptop.

There are possibilities for error with stroboscopes. [Adam] discovered that if the stroboscope was flashing at a multiple of the blade’s rotation speed, the blades would appear frozen, and he’d get an erroneous RPM value. Thankfully, [Adam’s] Vitamix had asymmetric blades, which made the test a bit easier. He calculated his blades to be spinning at 380 RPS, or 23,000 RPM. Not satisfied with his results, [Adam] brought out Audacity, and ran a spectral analysis of the blender in operation. He found a peak at 378Hz, which was pretty darn close to his previous measurement. Since the blender has a 4 inch blade this all works out to a blade tip speed right around the claimed value of 270 MPH. We’re glad [Adam] found an answer to his blender questions, but our personal favorite blender hack still has to be the V8 blender created by the Top Gear crew.   [via HackerNews]

Finally, Someone Has Found The Any Key

June 13, 2014 by 20 Comments

 

keyboard and any key device

“Where’s the any key?” Well, it’s right here. After running into trouble with the STM platform, [lukasz.iwaszkiewicz] went with the Texas Instrument C Series Launchpad to construct his “Any Key” HID device. He was able to make use of the TI TM4C123G LaunchPad’s extensive USB library which is laid out into four tiers – the very top tier being Device Class API. This gives the programmer the ability to implement simple devices with just a few lines of code. [lukasz.iwaszkiewicz] points out that ST does not have this option available.

The Any Key uses a host PC program that allows the user to enter keystrokes into a virtual keyboard. This information is then passed to the Any Key device. When it is pressed, it will push the recorded keystrokes back to the host PC. Simple, but effective!

The project is completely open source, and all files and code are available. Be sure to check out the video after the break demonstrating the Any Key in action.

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Faster Benchmarks With Slower Hardware

June 13, 2014 by 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.