Inter Arduino communication

This is a good place to learn about inter-arduino communications.

http://absences.sofianaudry.com/en/node/10

I2C BUS : Stands for Inter Integrated Circuit. It basically is a protocol for communication between different embedded devices and sensors.. Like accelerometers, temp sensors, embedded controllers etc...

In case of arduinos, just hook up all the Analog 4th pins together and 5th pins together. Use a pull-up resistor of 1-2Kohm between +5V and these pins. Also if you are using different power sources, do remember to share them. That is to connect all the +5 together and GND's together. Careful not to short them.

In case of Arduino's we make use of the wire library, to make the I2C communications easy. Thats all... :)