Thinking Outside The IDE To Make A Fast-counting Arduino

July 11, 2012 by Mike Szczys 38 Comments

[Udo Klein] took on the challenge of counting as fast as possible using an Arduino board. The quest involves a search for short-cuts that will let him drive a 20-bit counter as quickly as possible using the stock hardware. But the catch is that the Arduino environment has some overhead running in the background which will slow things down. He looks into each of these road bumps, then shows one way to get around them.

The code uses a command we don’t normally see in modern C embedded programming; the goto statement. He’s using this to bypass the extra cycles used by the Arduino’s in-built loop() function. The only command that is run within his hacked loop is a deeply nested set of macros. They’re toggling output pins using the hardware XOR built into the AVR chip. This is directly addressing the registers and thereby dumps the slowdown added by the digitalWrite() function.

The result is a software counter that toggles the output lights (see the clip after the break) at about 98.9% of the hardware clock speed. Pretty impressive, but [Udo] figures he can make it just a bit faster yet.

Continue reading “Thinking Outside The IDE To Make A Fast-counting Arduino” →

EMIC2 Text To Speech Module

July 11, 2012 by Mike Szczys 30 Comments

This is the EMIC2 text-to-speech module. You can see from the logo on the bottom left it’s the latest gadget coming out of [Joe Grand’s] Grand Idea Studios. [Dino] tipped us off about his first experience with a prototype of the board. He’s driving it with an Arduino and the video after the break shows that the sound rendering is high quality and the words are very easy to understand. One of the things that we think is interesting is that the serial communications used to drive the board are not uni-directional. In fact, there’s a serial terminal that provides documentation on how to use the chip. Obviously this is most suited to the Arduino, which always has a PC-side terminal window available to it.

[Joe] himself shows some of the potential for the board. He gave new life to a broken toy by replacing its internals with a PIC-based circuit to drive the EMIC2. That video is also found after the break. He’s just using the demo clips, but from that you will get a good idea of the vocal modulations this device is capable of. The board rings up at $60 and is available from Parallax.

Continue reading “EMIC2 Text To Speech Module” →

Playing Footsie With Your Video Games

July 11, 2012 by Mike Szczys 8 Comments

[Jon] will be tapping away with his toes during gaming session thanks to this foot controller which is packed with buttons and sensors. It’s the second iteration of the build. The original had some solder joints break and the USB stopped working. He had also been experiencing some erratic behavior and so he decided to upgrade the control hardware and add a few more things in the process.

This version uses an Arduino Uno as the interface board. He did a bunch of prototyping to find the best way to hook up all the analog sensors, and how to properly debounce the buttons. Once he was happy with the inputs he set about finding a better way to use the USB HID standard with the device. We were surprised to hear that the ATmega16u2 (one of the new AVR chips which includes USB hardware) doesn’t play nicely with Linux. But [Jon] managed to hack his way around that issue and now he’s gaming with an even better foot controller than before.

Time-based One-Time Passwords With An Arduino

July 11, 2012 by Mike Szczys 13 Comments

Get your feet wet with Time-based One-Time Password (TOTP) security by building your own Arduino OATH system. OATH is an open standard authentication system that provides a platform to generate tokens, making your login more secure than a password alone would.

The TOTP approach is what is used with many companies that issue hardware-based dongles for logging in remotely. This security may have been compromised but it’s still better than passwords alone. Plus, if you’re building it around an Arduino we’d bet you’re just trying to learn and not actually responsible for protecting industrial or state secrets.

The hardware setup requires nothing more than the Arduino board with one button and a screen as a user interface. Since the board has a crystal oscillator it keeps fairly accurate time (as long as it remains powered). It will push out a new token every thirty seconds. The video after the break shows that the Arduino-calculated value does indeed match what the test box is displaying.

Continue reading “Time-based One-Time Passwords With An Arduino” →

Cheap As Chips Arduino Ethernet Shield

July 10, 2012 by Brian Benchoff 51 Comments

It’s no secret that Ethernet shields for the Arduino are a little expensive. With the official Ethernet shield selling for about $50 and other options not much cheaper, there’s a lot of room for improvement for Arduinofied Ethernet. [Boris] over at Open Electronics has a solution to this problem: his Ethercard powered by a $3 Ethernet controller.

The Ethercard uses the Microchip ENC28J60, a through-hole Ethernet controller. There isn’t much else on the board apart from an RJ45 jack, caps, resistors, and a cheap buffer chip. This board was designed to be easily produced, and we’re thinking it might be possible to etch this board at home.

There are a few drawbacks to this ENC28J60 Ethernet shield – the official Arduino Ethernet shield has a 10/100 Mbps connection where the Microchip-powered shield is limited to 10 Mbps. Given the reduced cost, ease of assembly, and the fact that it’s pretty hard to saturate a 100Mbps connection with an Arduino this flaw can be easily ignored.

Pretty neat, especially considering how much you can do with an Ethernet connection on your Arduino. Files and code available in the git.

Exercise Bike Actuates Your Download Speeds; Messes With Music Playback

July 10, 2012 by Mike Szczys 7 Comments

We’re not featuring this project because it involves the tiniest exercise bike in the world. It’s on the front page because the speed-control features which this dynamic duo added are hilarious. They call it the Webcycle and it’s actually two hacks in one.

Way back in 2009 [Matt Gray] and [Tom Scott] slapped an Arduino on the bike and used it to measure the revolutions of the cranks (how fast your feet are going in circles). This was hooked up to the laptop which is fastened to the handlebars. This way you can surf the Internet while you work out, but the bandwidth is directly affected by pedal speed. If you want to watch video you’re going to have to sweat…. a lot. Check it out in the clip after the break.

This March they pulled the Webcycle out of storage so that it may ride again. This time it’s connected to the sound system in their exercise room. A record player motor is the victim in this case. You guessed it — pedal speed dictates the rate of the turntable, modulating the pitch drastically. Make sure the boss isn’t around when you watch this clip because it will be hard not to guffaw.

These guys really have fun with this hacks. It was [Tom’s] birthday that prompted that hacktacular mini golf course.

Continue reading “Exercise Bike Actuates Your Download Speeds; Messes With Music Playback” →

Building A Homebrew Diesel ECU

July 10, 2012 by Mike Nathan 18 Comments

arduino-diesel-ecu

Over the years automobile engines have become increasingly complex, and with this added complexity comes an increased reliance on intricate computer systems to run them. These control systems are typically the fruit of many hours of research and development, carefully protected by the auto makers who create them. Instead of relying on a closed system to power his car, a Finnish hacker that goes by the name [synkooppi] has decided to do away with his diesel engine’s ECU altogether and build one of his own with little more than an Arduino.

As you can see from his web site, [synkooppi] has created his DIY ECU using an Arduino Mega, which is capable of controlling diesel engines that employ a Bosch VP37 or other inline diesel pump. So far he has all of the basic workings in place, which allow him to run and control an Audi diesel motor.

While many details about his homebrew ECU are hard to come by, he does have a series of development videos posted on YouTube which should help satiate inquisitive minds. For those of you with a spare diesel motor laying around, [synkooppi] has made the first release of his code available to try out.

Stick around to see a video of the ECU in action.

[Thanks, perhof]

Continue reading “Building A Homebrew Diesel ECU” →