u can't, but u can get ur code in other people's pal pad.
in Pokemon pearl you can only get dialga by trading with a friend that has diamond or you can trade for it at the gts
You need to have Pearl or trade with someone who has Pearl.
no you can`t catch dialga in Pokemon pearl you have to trade for him on the gts
there has not been one made. There is no code but if you get the pokedex compete code, you can go to the GTS. I did that and i have ALL the legendaries! -Hawkfur
Currently, there is no code for cloning a Pokemon with a cheat device. However, there is a way to do it without one, and were you not a cheater I would tell you. It involves the GTS.
if you put one in offer in the gts you cannot get it back . SORRY!
You can get it only from Pokemon Diamond/Platinum or the GTS.
The Global Trade System(GTS)!!
gts in jubalife
first gymbadge (orburgh)
Global trade station
Haunter evolves into Gengar by trading. Since the GTS is not functional in Pokemon Diamond and Pearl anymore, you will need to ask a friend, who has a copy, to do a trade-back with your Haunter.