I2c address of UNO

Using Arduino Programming Questions
#1

I have 2 UNO’s connected via A4 and A5 pin, and sharing ground. They’re both plugged into a USB and getting power from there. One is master and the other is slave, my question is how do i get the address for the slave?

When i use Wire.begin() on the master, that’s setting it as a master, but when i use the same on the slave, what address do i give it? Am i setting an address that i can choose randomly or do i have to put in an specific address? If specific, how do i go about finding this?
Ive seen videos of people using a single number for the address and I’ve seen some using 0x23 for example

The scanner seems to keep giving me an error when trying to download, but I’m not sure if i should be using it since I’m not using some other i2c device such as a physical serial monitor. I hope this makes sense

#2

The slave's address is set when it calls Wire.begin(). See the Wire library examples in the Arduino IDE.

#3

gfvalvo:
The slave's address is set when it calls Wire.begin(). See the Wire library examples in the Arduino IDE.

Oh, so i set it to whatever i want? (Within reason)
Ive done quite a bit of research on it and can’t find anywhere if I SET it or use an already set address

#4

You can set the I2C address of the Uno to any unused address that is not reserved.

#5

groundFungus:
You can set the I2C address of the Uno to any unused address that is not reserved.

Gotcha, thanks very much!

#6