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397 Articles

Head Bangers Beware: Motion Sensing Headphones

September 14, 2009 by 9 Comments

tiltphones

The iPhone doesn’t have the market cornered on the use of accelerometers. The tiltphone project incorporates a three axis accelerometer into a set of headphones transforming them into a remote control for an iPod. A PIC16F690 reads in data from the analog sensor, translates specific movements into commands, and like the Arduino iPod Remote from last week, relays them to an iPod via the Apple Accessory Protocol. A quick nod left or right skips tracks, holding a sideways nod controls the volume, and setting the headphones down pauses.

This project is a bit older but we’re glad [anon] tipped us off as we hadn’t seen it before. There doesn’t seem to be any code or schematics available but because the Apple Accessory Protocol is known, it’s only a matter of working out how to interpret the sensor data. There is video after the break and if you pull off this hack yourself be sure to send in details for a followup.

Continue reading “Head Bangers Beware: Motion Sensing Headphones” →

Controlling An R/C Car With A Pic16F84

September 12, 2009 by 27 Comments

[youtube=http://www.youtube.com/watch?v=0hoFxx1EaN8]

[GuySoft] sent in this project. He doesn’t normally mess with electronics, but decided to give it a try. He chose a fairly complicated project to be his first, but seems extremely comfortable with it. This project was to control his R/C car with a pic16f84. That chip was chosen simply because it was the only one available at local stores. Though we’ve seen much more complicated projects in the past, he does a great job of showing exactly what has been done. He shares his thoughts and source code with us as well. He has express a little frustration about the closed source compiler he was using, so if anyone has any suggestions for him, he would probably appreciate it.  The funny part is that he mentions that people would just tell him to “get an AVR”. We think the readers here will probably be happy with how he pulled it off.

Cellphone-controlled Home

September 6, 2009 by 9 Comments

[youtube=http://www.youtube.com/v/exTpD0–BCo]
[Tixlegeek] used a Motorola 68HC705J1 development board to remotely control his home through his cellphone. The video above, as well as [Tixlegeek]’s website, is in French, though the video has been captioned. The development board (called the ERMES125) is controlled by a PIC externally. It has an array of LEDs, and apperantly a few high voltage relays. The PIC is connected to a laptop through a serial interface. The laptop is running a small web server, which uses CGI to control the PIC from a webpage. This system allows [Tixlegeek] to log onto the webpage from his web enabled phone, click a few buttons, and have appliances turn on or off through relays controlled by the PIC (via serial signals from the laptop).

Single Tube Nixie Clock

September 3, 2009 by 20 Comments

[youtube=http://www.youtube.com/watch?v=a-7QAWshEXo]

This single tube nixie clock cought our eye today. After receiving an IN-8 tube from a friend, [Trax] wanted to find some project to show it off.  He decided on an art piece that doubles as a clock. Tastefully mounted in a simple wooden box with a pretty inlay, the tube is lit from below with a green LED that pulses every second. A single button, located on the back, out of view is pressed to request the time. You can see the time being displayed on the video above. To see the guts and read about how he’s using the PIC16F84’s built in clock to keep track of time, check out his site. Even though this is a Nixie, it reminds us of the Decatron kitchen timer we saw recently.

[via Hacked Gadgets]

Tiny GSM Alarm System

September 1, 2009 by 21 Comments

[youtube=http://www.youtube.com/watch?v=W746qoZsrEs]

We’ve covered this sort of thing before, but there is something to be said for the simplicity of this tiny GSM alarm system by [trax]. The alarm system is designed to send the owner a text message when a sensor is triggered. This alarm only works with Siemens phones, but it shouldn’t be too hard to find one.  The alarm is configured via a dip switch on the board and can also be armed and disarmed by text. The brains of this system is a PIC16F84A. The code and schematics are included at the bottom of the page.

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USB Gameboy Cart

August 28, 2009 by 20 Comments

gamecart

[Jose Torres] sent in his latest attempt at creating a custom Gameboy game cartridge. We’ve featured his projects before, and he’s come a lot closer over the last 2 years. He’s aiming to create an easy interface for homebrewers that doesn’t require any other special equipment. In this revision, he’s using a PIC and a memory controller to interface between an SD card and the Gameboy. The cart also has USB support for uploading files to the SD card and reprogramming the PIC. Because it’s just USB mass storage, it will work on almost any modern OS. He’s currently testing the device, but hopes to be selling them soon for $40.

Interfacing A Digital Rotary Switch

August 27, 2009 by 19 Comments

digital_rotary_switch

[hw640] has put together a well written and detail packed explanation of how to interface with a digital rotary switch. These digital opto encoders have just two outputs with four possible logic levels (00, 10, 11, 01). The relative position of the switch is insignificant but the direction of rotation is what matters.

The short and dirty: Each of the switch’s 2 output pins is attached to a pin change interrupt on the microcontroller. Every time the switch moves it generates either a rising edge or a falling edge on one of the two pins; both edges cause an interrupt. By checking which pin caused the interrupt, then comparing the logic levels of the two pins after that interrupt, we can determine the direction the switch was rotated.

Although this explanation uses a PIC and code written in PicBasic Pro the concepts are discussed in the abstract and would easily be adapted to an AVR or another microcontroller of your choice.