Hi all 
I'm working on connecting multiple arduinos boards to a central raspberry pi board to do some home automation.
I worked on 2 arduino modules yet and now I would try to connect them to raspberry and keep a log of arduinos data there.
But I have some question:
- which protocol (serial, I2C, etc) is better to use? The network type is like "star network" and the distance from raspberry and some modules can be around 10-20 meters too.
- Is it better to let raspberry asking to each arduinos for data, or let each arduino send data autonomously?
Thank you so much to everyone who can help me