i2c beginner question


I successfully plug an i2c RTC clock with my Arduino board.
Now, I have other i2c components that I would like to plug also (EEPROM for example, and probably more to come).

What kind of electronic component should I buy (not a serial to parallel Shift-register I guess… )?

Does someone has an example of such a wiring? … may be also a piece of code :wink:

Thanks !

What kind of electronic component should I buy

One with a different address to the first device.

well, does that mean that I only have to put them in series? :-/

No, I2C is a bus, the devices are in parallel.
All the SCLKs are connected together, and all the SDAs are connected together.

ok, so what is the purpose of the i2c i/o expander I saw here: http://www.neufeld.newton.ks.us/electronics/?p=241&cpage=1

is it needed only if you have the same address?

That device is a way of adding extra digital I/O pins to a design, it isn’t any kind of bus repeater.

ok, I think it is clearer now. Thanks