Getting hands on Arduino Ethernet Shield

  Updated! Arduino Ethernet code Since last Arduino Ethernet code there we several Arduino IDE releases with changes that affected the source code listed in this post. Due to high interest, we updated it with minor modifications to make it work as expected. The biggest problem occurred because Wstring.h library isn’t any longer in use, because String.h library is included in the core that brings some difference in several functions used in the code. In code we need to write readString += c; instead readString.append(c); if(readString.indexOf(“L=1”) >0) instead if(readString.contains(“L=1”)) Also we need to re-import Ethernet.h library in order to bring along all necessary libraries like Client.h, Server.h, SPI.h, Udp.h. The other problem occurred when program run was that LED never lights up when the checkbox is selected. I used Serial.print(c); to track down the problem. And it seems that method GET sends two strings: Our code was catching and analyzing both strings. We only need to take string where the parameter is sent: “GET /?L=1 HTTP/1.1” and skip “GET /favicon.ico HTTP/1.1”. As our example is straightforward we can see, that second string lacks “?” symbol. So we check the string if there is a ‘?’ symbol, of not, skip whole…

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Running TX433 and RX433 RF modules with AVR microcontrollers

Sometimes in embedded design, you may want to go wireless. Maybe you will want to log readings of remotely placed sensors, or build a remote control for robot or design an alarm system. Radio communications between two AVR microcontrollers can be easily set up with specialized modules. Let us try to run very well-known RF modules TX433 and RX433 (or similar) that can be found almost in every electronics shop. The pair of them cost less than 15 bucks. Transmitter and receiver modules are tuned together to work correctly at exact 433.92MHz. The transmitter can be powered from 3 to 12V power supply while the receiver accepts 5V. The 5V is standard for AVR microcontrollers, ideal for 5V devices. Modules do not require addition components – apply power and connect a single data line to transmit data.

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New project batch from Cornell University ECE 4760

It’s been a regular tradition every spring to check out on what’s new in Cornell University ECE 4760 final microcontroller projects. This year isn’t an exception. It seems that they started a 2010 list on new great AVR ATmega644 projects. List is still building up but there already is a 20 project list with projects like Human Tetris, Glove Midi Controller, Talking Voltmeter and other. All projects are compiled with WinAVR/GCC tools – so everyone can take a glance and give a try. It’s a great list of projects starting from 1999 so there are tons of great interfacing examples, code snippets and even ideas for your new project. Keep eye on that lists as there are more to come (it always reaches about 40). Way to go ECE 4760!

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Sticky Light – The Art of Pure Light Interaction

People always say that it’s impossible to catch a light, as the light moving in a very high speed. However, if you’re giving the opportunity to grab and hold the laser light in your palms, would you mind to give it a shot? As you can see on the above picture, a person is holding the red laser light inside his/her hands. Theoretically, it’s a laser spot bounces on a figure being drawn on paper and trying to escape the labyrinth of lines. No camera or projector is used in the experiment. The Sticky Light proposes an experience and allows the users to touch and interact with a beam of pure light. It even fun, when you can play the classic PONG game with this Sticky Light all with your bare hands!

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The Connection of Open-source Camera with Digital Photography

Did you know that the camera is one of the most ancient inventions, which is having nearly a thousand years of history? According to history, the idea of the very first camera had been recorded in a book called, “Book of Optics” in 1015 by the incredible Arabic scientist Ibn al Haytham (Alhazen). Believe it or not, Alhazen, which is also known as “Ptolemy the Second” was the first person who proved that light travels in straight lines. He recorded the theory in the Book of Optics as well! This book had an important influence on the development of optics, and that’s why Alhazen is also being known as the “Father of modern optics.” Well, time marches on, and we’ve already come to the 21st century, where the digital and optic cameras have been part of our life. Marc Levoy, a professor from Stanford University, California, has been trying to develop a new type of camera. He called his invention as “Frankencamera” (Hmm…, maybe it has something to do with Frankenstein?). He described that the open-source digital camera is no longer be limited by the software; instead, the programmers have the chance to build up new software to teach the…

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MattsOffice – The Wonderful Home Automation via Twitter!

How long you’ve used the internet? Well, if you’re still a newbie, then you might never hear about Twitter before, but for those people who have been an internet users for couple of years, they are very familiar with the social networks, such as Facebook, Myspace and Twitter. By the way, as one of the engineer who frequently surfs the internet, Matthew Morey, had invented the smart “MattsOffice”, which is a home automation via Twitter. Morey himself is a big fan of Twitter. He always wants to build a home automation via Twitter that allows him to have the connection through various types of household appliances, such as personal PC, iphone, GPS and much more. According to Morey, there’s one thing that lacking in most of the devices, which is the 2-way communication between Twitter and the device. Normally, you’re able to send an update to Twitter, but are never performing an action based on a Twitter message! However, Morey had found the solution, and applied it on the MattsOffice. He mentioned that the MattsOffice is a perfect device; which is possible for you to send a command by placing a keyword in a @reply message. Let’s say if you…

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The Powerful R/C Steam Turbine Tank

Are you having the guts to play with fire? Hmm…, if you don’t mind to look by other like a freak and would do anything to stand out from the crowd, then you might want to build this powerful R/C steam turbine tank. This R/C steam turbine tank is a very instructable project made by crabfu. Actually, it built based on an R/C machine that is carrying flammable gas (That’s why we should watch out with it, as you’re playing with fire here). It able to produce extremely high steam pressure, which is capable of causing fire alarm to be responded on it! In order to handle this “hyper fire monster”, you must pay proper attention, or you’ll be suffered with blisters on your finger, or even get your house burnt down instantly!

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