Effortlessly Communicate Between Two Arduinos with Just Two Wires!

Thanks for the video ,i have a question , if i use an uno with pin 4 and 5 used for my i2c lcd as my main controller and i use a n nano with a rotary controller would i t be possible to use pin 27 and 28 for the connection and will it work . secondly when i send an int that is determined by the rotary count on the rotary controller how do i insert that value in an int . lets call it "Pause" on the uno

Thank you for a great tutorial. I have a few questions about the initial test code.
First, since you didn't set a pin number, how is LED_BUILTIN working?
Second, in your "inverted" function, your declare the variable "led", but there is no reference to pin 13, the built in LED. How does this work??? Thanks very much.

can i connect more than two arduinos?

Note that I think this will only work up to about 1 meter apart since it uses the I2C interface. Slowing down the baud rate of that interface could make that a little longer at the sacrifice of throughput.