Precision Frequency Measurement Library For 8-bit Microcontrollers

[Paul] has been working on porting over Arduino libraries for use with the Teensy microcontroller platform. This tends to be pretty simple since they both use the same Atmel chip architecture. But once in a while he finds the Arduino libraries are not what they’re cracked up to be. When looking to port over a frequency measurement library he ended up writing his own that works better and is much more portable.

He had two big beefs with the Arduino Frequency Counter Library. The first is that it required the compensation factor the be calibrated using an accurate frequency counter. That’s a chick-and-egg problem since many people who build a frequency counter with an Arduino are doing so because they don’t already have a standalone tool. The second problem is that the Arduino library was hardcoded for ATmega168 or ATmega328 chips.

This new library fixes both issues with just one trade-off. Your hardware setup must be using a crystal oscillator. You can see above in the image above that the frequency measurement is quite accurate with this method. The package also uses a thin abstraction layer which will make it easy to port to any 8-bit microcontroller which is programmed in C.

I Am Root! – IP Camera Shell Access

[Shawn] emailed us some pictures and a description of his latest hack. He cracked open a Rosewill RXS-3211 IP Camera because the output of the web interface made him certain that it was running Linux and he wanted to unlock some more potential from the device. These cameras are used for security, and offer a browser-based interface via a WiFi connection. After studying the circuit board he started poking around an unpopulated set of four pads and managed to get a serial connection up and running. The device’s serial terminal operates at 115200 baud using eight data bits, one stop bit, and even parity.

He wonder where to go from here and we have a few ideas. You can see in the terminal readout above that it announces when motion is detected. We think this motion detection would be quite useful with a small rover while adding live video broadcasting at the same time. An embedded Linux system should be able to interface with the device and we think that a bit of creative coding would open up the WiFi connection for other use as well. Not bad for a module that can be had for as little as $29. We’ve included all the images [Shawn] sent us after the break and we’d love to hear your thoughts on what you’d use this for in the comments.

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DIY Inkjet Printer Begs To Be Hacked

diy_inkjet

[Nicholas C Lewis, Patrick Hannan, Jared Knutzen, and Joy Markham], students from the University of Washington, have recently taken the wraps off a project which they have been collaborating on, a DIY inkjet printer. The group set out to construct a low cost, open source inkjet printer for personal use that utilizes standard inkjet technology. Their working prototype, pictured above, satisfies all of those requirements, making it an ideal device for the at-home hobbyist.

The printer was constructed from easy to obtain components such as steel rods and stepper motors, along with other parts that can be printed using a RepRap or similar machine. An Arduino Mega manages the steppers and repurposed print head, recreating whatever Processing-generated image it has been given.

The printer is quite a hit so far, and people are already talking about adapting the design to print on spherical objects (think EggBot), to create direct etch resist PCBs, and more. We think it would make a great direct to garment printer with just a few small tweaks.

Check out the short video embedded below to see the printer in action.

[via Make]

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Update: Laser-powered Auto Focus Assist Version 2

We don’t know if our feature from a couple of days gave [Adrian] a kick in the pants, or if he was just on target to finish is writeup this week, but he’s posted about version 2 of his laser auto focus assist project.

The original idea was to use an unfocused laser pointer dot to give his DSLR auto focus feature a kick in the pants since the built-in light doesn’t come back on when photographing moving subjects. The original version worked, but he had to operate the laser manually and the hardware was kind of spread out all over the camera.

The latest version (2.0) can be seen above, housed in a project box that mounts to the hot shoe and keeps everything together in one package. The laser operation is now automatic, coming on when the shutter trigger is depressed half way, or when the auto focus enable button is depressed. The controls on the project box include an on/off switch as well as a potentiometer which varies the intensity of the laser.

It looks like this won’t be the last version of the hardware that we see. [Adrian] covers a few outstanding problems in his post. Most notably, the laser light is still a bit too strong. At a recent live event, another photographer took issue with the fact that his images included the red splotch from [Adrian’s] diy hardware.

Fan Throttling For PS3 Temperature Control

This setup will let you monitor Play Station 3 temperatures and throttle the cooling fan accordingly. [Killerbug666] based the project around an Arduino board, and the majority of the details about his setup are shared as comments in the sketch that he embedded in his post. He installed four thermistors in his PS3 on the CPU heatsink, the GPU heatsink, the Northbridge or Emotion Engine, and one in front of the air intake grate to measure ambient room temperature.

Above you can see the setup he used to display temperatures for each sensor on a set of 7-segment displays. The project also includes the ability to push this data over a serial connection for use with a computer or a standalone system.

The project is still in a prototyping stage. It works, but he likens the fan throttling to the sound of a car engine constantly revving. Future plans include smoothing out the fan speed corrections and scaling down the size of the hardware used in the system. We’d suggest doing away with three of the displays and adding a button that lets you select which set of sensor data you’d like to display.

[Thanks User]

Cube Solving Robot Shatters The World Record

This cube-shaped bot just shattered the robotic Rubik’s Cube solving record by about 8 seconds. It did it in a blazing 10.69 seconds to best the old record of 18.2 seconds. There was immediate confusion here at Hackaday as some of us thought the record was actually around six seconds. And it is, for humans. That’s right, the human record holder completed a cube in 6.24 seconds… faster than a robot by almost four seconds. It’s surprising that we can still beat mechanized devices at some repetitive mechanical operations.

Take a look at the speed run shown in the video after the break. What strikes us is that the motions are incredibly efficient, and the bot is very quite. Compare that efficiency to CuBear, a solver that uses a different motor for each side of the cube. That one doesn’t need to grip the cube making us think it could beat this version if the firmware were quite a bit faster.

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