if it was not logic.. you also need to be connected to wifi-network. That you can configure in the game menu, just go down to one of the "wifi's" you will understand soon which one it is. That would simply be like connecting your laptop to your wireless network
the friend codes thing, is friends codes that you register in you "pal pad", under -key items- in bag
so if you know any friends gamins gen IV( HeartGold, SoulSilver, Diamond, Platinium, Peral) pokemon add them to your friendlist.
then you can trade in the basement of pokemoncenters with them, which commando did mention.
FC HeartGold: 1334 2351 1649
Since you are already reading my sig, check out my trading thread to My trading thread! Offering Gen3 legendaries among other stuff.