Hello people. I just ordered a 20x4 I2C display and I’m looking at how to connect it to the Uno. When I look at the examples, they are using the A4 & A5 pins on the Uno for the SCL & SDA connections on the display. Why not use the SCL & SDA pins next to the AREF pin on the Uno board? This is very confusing to a newbie. Thanks folks.
Older versions of the Uno board did not have the pins next to the Aref, so A4 and a5 were used. Now they are identified separately but they are still the same pins (connected in parallel). You can use either - it makes no difference - but in your code they would be identified as A4/A5 if you need to reference them.