The Arduino platform should be perfect for throwing together a lightweight webserver because of the availability of quality shields that take care of the hardware for you. As [Ovidiu Predescu] found, there are a few hiccups along the way and he’s put together a guide that covers the workarounds. Specifically, using an Ethernet shield and data logging shield at the same time produces a bus conflict which he sidesteps by cutting the CS pin trace on the data logging board and moving it to a different pin. There is also a bug with one of the chips on the Ethernet shield that is fixed using a similar method. So if you’re not just going to etch your own webserver hardware maybe this is the next best thing.
ethernet147 Articles
Swarm Light At Art Basel
What has 9000 LEDs, 3000 MSP430 processors, six XMOS XC-2 Ethernet modules, and goes blinkity-blink-blink? It’s Swarm Light, an art installation shown at this year’s Art Basel exhibition. [Fredrik Petrini] worked on the hardware that went into building the group of three 3D cubes of LED light modules. Unlike so many art pieces we see he shared the design details of the piece. In the image above you can tell that each cube encompasses several rods of LED modules. Each rod as three rails that provide power, ground, and serial data in addition to serving as the physical structure. Each module has three LEDs on it controlled by one MSP430 processor. The XMOS units each control half of the rods in a cube, getting their instructions over an Ethernet connection from a PC running a program on a .NET framework. It would be an understatement to say this is just a upscaled LED cube. Check out the exhibit in action after the break. It uses an algorithm to analyze the music, taking input from the ambient sound in the room, to control the light fluctuation.
Simple Way To Fix That Broken Ethernet Cable
Chances are you’ve come across an Ethernet cable where the small plastic tab that holds the plug in place has broken off. We have a crimper on hand and usually just throw on a new RJ45 connector but [Laxap] found a simple alternative to fix Ethernet plugs. By using a couple of correctly sized cable ties you can secure the damaged connector without replacement. The boxy locking mechanism on the end of the cable tie is used as the catch, slimmed down with the help of an X-Acto knife or razor blade. Once you’ve got the right fit, use a second cable tie to secure it to the Ethernet cable. Simple is brilliant.
[Thanks Password]
Internet Controlled Scrolling Numitron
How’s this for a first microcontroller project: a ticker that pulls messages from the Internet and scrolls them on a set of numitrons. [David Barton] built this using an mbed microcontroller. Tapping an ethernet library he got this to pull data from his server by connecting directly to the cat5 cables. The display consists of three numitrons which are incandescent 7-segment displays. In the video after the break you can see him sending messages to it from his iPod touch. This is just a PHP form that writes the submitted message to a file for the mbed to read. As [David] points out, there’s obvious Twittering applications here, but we just like the way it looks! Continue reading “Internet Controlled Scrolling Numitron”
Replacement Refrigerator Controller
[Michael] got his hands on a refrigerator that he intended to store beer in but found that it ran constantly. Instead of buying a new thermostat he and his friend [Doug] set out to build an Arduino-based controller for the fridge.
The finished project will switch 240v so they’ve used a transformer to power the logic circuitry and a solid state relay to handle the load switching, with a Dallas 1820 for temperature data. Because the Arduino offers more capabilities than the average thermostat hack they also decided to tap into its potential by adding an Ethernet shield. We see the Arduino as a prototyping device and so do these folks. Once the bugs in their first PCB prototype are worked out the circuit will use the ATmega328 and do away with the Arduino.
[via @littlebirdceo]
Temperature And Electricity Monitoring
[Willem] has been using an Arduino to monitor temperatures and electricity usage. For the temperature monitoring he picked up some 1-wire temperature sensors similar to those we’ve featured in the past. To pick up on electricity usage he’s not using an amp sensors, but because he’s in the UK he does have a flashing LED on his power meter. There’s a known trick to pick up these flashes with a photo cell to calculate energy usage based on meter readings. Finally, the data from the three sensors (indoor temp, outdoor temp, and energy usage) is piped over the Internet via an Ethernet shield so that it can be collected and graphed.
[Willem] has had the system running for a year. If you’re nosy you can look at the temperature graph generated from his collected data.
IPv6 To 1-wire Protocol Translator
[Fli] assembled an AVR based system that can assign IPv6 addresses to 1-wire components. An AVR ATmega644 microcontroller is used in conjunction with an ENC28J60 ethernet controller chip. To get up and running with IPv6 on this meek hardware [Fli] ported the uIPv6 stack from the contiki project over to the AVR framework. Although he encountered some hardware snafus along the way, in the end he managed to get five sensors connected to the device, each with their own IP assigned using the stack’s alias capability.
This is great if you’re looking for a low-cost IPv6 solution. We’re not sure if there’s much demand for that, but it’s useful for that 1-wire home automation setup you’re considering.