arduino

2943 Articles

Capacitance Sensor Guide (AD7746)

July 18, 2009 by 20 Comments

capacitive_sensor

[Marcus] has written up his experiences using the AD7746 capacitance sensor. He used the SparkFun breakout board in conjunction with an Arduino. The available Arduino code wasn’t that great so he rewrote it to be easier to understand. The AD7746 is an I2C device that can be continuously read, but this doesn’t mesh well with the Wiring libraries. Additionally, the calibration routine from the data sheet is difficult to understand. He’s included all of the code he used plus a Processing sketch to help visualize the input which will hopefully make your experience with the chip much more smooth.

AVR ISP Programming Via Arduino

July 15, 2009 by 32 Comments

ardunio avr isp programming

We found this Arduino AVR ISP programmer particularly interesting. AVR microcontrollers can utilize an interface called In-System-Programming. ISP allows the chip to be programmed or reprogrammed while in an actual circuit via a pin header. Atmel’s solution is the AVR ISP MKII programing tool. The MKII can also be reprogrammed just as an AVR. The difference here is that most people are not likely to modify the MKII to be used as anything but a programmer. On the other hand if you already have the Arduino, fetch the avr.isp.03 firmware and AVRdude. Then program a device, for example an ATtiny13 using the Ardunio as the programmer. All the project information is provided under the CC BY-NC-SA 3.0 license. On a related note we covered a Microcontroller cheat sheet which covers AVR devices and ISP pinouts.

Arduino Nano Updated

July 13, 2009 by 22 Comments

The official Arduino Nano design has been updated to version 3.0. Like other new Arduino designs, it’s using the ATmega328 instead of the ATmega168. It’s also a slightly more reasonable $35. The small board is designed to be plugged directly into a breadboard and accessed via mini USB cable. This new design is also two layers instead of four making it easier to produce and modify. The new Nanos will ship at the end of the month.

Smart Can Crusher

July 10, 2009 by 15 Comments

[vimeo http://vimeo.com/4821403%5D

[Mangonha] has put together this interesting project involving aluminium can recycling (translated, sortof). They’re using an arduino to tally up how much aluminium they have accumulated. That information is then passed on and displayed on a google map. There are families that go around collecting the cans as a means of income, and this system could be very helpful to them. They state that their goal is to eventually have restaraunts and more families included. We’re a bit curious about how helpful this really is. How is that information actually changing the actions of the collectors? Would a simple flag on your door or window signalling enough cans to pick up or not be just as effective?

[via the Make flickr pool]

Home Power Monitoring

July 5, 2009 by 25 Comments

powermonitor

Reader [john] finished up his home power monitor over the holiday weekend. It uses a pair of current transducers clamped onto the mains. These output 0-3V and are read by the Arduino’s ADC. The Arduino averages samples over a 20 second period, calculates power used, and uploads it using an Ethernet Shield. The shield can’t do DNS lookups, so he uses a WRT54G to negotiate with the remote webserver. He admits that the system could be more accurate; it can’t detect small loads like wall warts. He also says that money could be saved by talking serial to the router instead of over ethernet. Here are the current usage charts.

You can find many power monitor projects like this in out Home Hacks category.

WTF-O-meter

July 3, 2009 by 25 Comments

wtf-button

Here’s something every office probably needs. Ours does at least. It’s a WTF counter. When the office gets just a little too weird, someone hits the button and it gets logged. It’s probably pretty easy to judge the day by the WTF chart. The button is connected to an Arduino that updates the status on a local web server. We can imagine a nice bar graph of WTFs per day, or possibly a pie chart with normal time vs WTF time. Unfortunately, imagining is all we’re going to do. They didn’t include any examples of the visualizations. Can you imagine saying something to a co worker just for them to promptly march over and slap the WTF button? Maybe we don’t need one.