Feasibility Question: Implementing I2C between ATmega328 and ATtiny85's

Hi all,

So I'm getting back into Arduino just a little bit for the winter and have one or two projects I'd like to take a stab at.

After accidentally zapping my second Arduino Uno (replacement) with a 12V rail, it had not occurred to me for almost a year that I could use a spare ATmega328P to build a breadboard Arduino and still use my LCD/RFID shields from Adafruit by connecting with I2C! I was pretty stoked about that :slight_smile:

Now, I'm looking to "daisy chain" or even "network" some Arduino's together in the following fashion:

  • ATmega328P - Master which will "assign" tasks to slaves or read data from slaves
  • ATtiny85 - Slave which will do work, sending data back to master

I'm aware that I2C isn't built-in to ATtiny85 and that USI has been used to fabricate it - I'm just curious how well this works with native I2C.

Basically, I want to be able to do I2C between an ATmega328P master and an arbitrary number of ATtiny85 slaves (i.e. 5).

Is this possible and have there been any updates released in recent months (i.e. new libraries) for implementing this sort of thing?


I'm just curious how well this works with native I2C.

It will work fine.
Just make sure it is the correct master or slave implementation.