voila un extrait d'un faq de gamefaqs qui explique en detail
Data Transferring [FEDT]:
Fire Emblem: Radiant Dawn is the sequel to Path of Radiance, and as
such, it allows you to transfer data to it. However, as of now, only
normal and hard mode epilogue save files can be used. Also, you must not
even have any form of an easy mode save on your Path of Radiance file
or the game will freeze up.
Now onto what actually transfers:
First, you can get stat bonuses for your characters. If a character
reached level 20 of their final class and capped a stat (or more) then
they will receive a fixed bonus to that stat (or stats) in Radiant
Dawn.
The Health stat bonus is +5 while Strength, Magic, Skill, Speed,
Defense, Resistance, and Luck get +2.
Some special cases, however, are Danved, Calill, and Sothe.
Danved will get all of the bonuses from Devdan since they are actually
the same person.
Calill will receive her own bonuses and any bonuses that Largo would
have received since he is not playable in Radiant Dawn.
Sothe will receive his exact stats from Path of Radiance if he reached
level 20 even if the Path of Radiance stat is lower than the base stat
in Radiant Dawn. Also, since his resistance cap is lower in Radiant
Dawn, if his resistance in Path of Radiance is 15-20, it will be 15 in
Radiant Dawn.
Next are the weapon rank bonuses. If a character's weapon type reached
C to S rank then there will be a weapon experience bonus given in
Radiant Dawn. The bonuses are 40 for C rank, 80 for B, 120 for A, and
160 for S.
Now onto Supports. Support conversations on a Path of Radiance epilogue
file can be viewed in the support library once you create a new
Radiant Dawn file using the Path of Radiance data. Also, 'A' level
supports in Path of Radiance will become bond supports between the
characters giving a +5 to critical and dodge.
Last, we have Coins which were previously thought to be useless. Now
any coins from the Path of Radiance epilogue file will transfer to
Ike's convoy at the beginning of Part 3. They now can give bonuses
to forged weapons.