For a project I have to use 3 or 4 arduino that will communicate using the i2c protocol.
But there is discordant information about the wiring.
One say that you can directly connect all devices on the bus without resistor: http://marcoramilli.blogspot.ch/2011/10/communication-between-multiple-arduino.html
Others say that I have to use a pull-up resistor for the bus wires: http://hacknmod.com/hack/how-to-connect-multiple-arduino-microcontrollers-using-i2c/
As I don't have time to make multiple tests, I ask you which one is the correct way of doing it ?
Thanks for your time