This instructable shows you how to build a Web-enabled tri-color LED based on an Arduino and the WIZnet Ethernet shield, controllable from any Web browser .
Check the live demo at http://try.yaler.net/~arduino/led
Because the LED is exposed through a simple RESTful web service running on the Arduino color changes can also be triggered by Pachube or other platforms offering Web hooks. Welcome to the Web of Things ! The LED can of course be replaced by a motor or a high voltage switching relay to enable more interesting browser controlled applications, e.g. for home automation.
Publishing your Arduino through the Yaler relay server makes the Arduino accessible from everywhere even if it is hidden behind a firewall or a NAT and does not have a public IP address. A single Yaler relay server instance can host many Arduinos (and any other device with a TCP Socket library, e.g. a Sheevaplug or an Android phone) and is available at https://yaler.net/ (Disclosure: I'm a founder of Yaler)
- Tri color LED [Adafruit | SparkFun]
- Arduino Duemilanove ATmega 328 [Adafruit | SparkFun]
- Arduino WIZnet Ethernet Shield [Adafruit | SparkFun]
- Resistors [1 x 150 Ohm, 2 x 82 Ohm for the Adafruit LED or
1 x 180 Ohm, 2 x 100 Ohm for the SparkFun LED]
- RJ45 cable
- Soldering iron
- Helping hands
- A / B USB cable
- Internet access with DHCP, no public IP address needed for Arduino
- (Optional: PC or Cloud Server with a public IP address, to run Yaler)