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You can read the full context on my user page, but basically when I started playing the Gen IV games, I ended up with a load of Gen III Pokémon which I had got on an emulator (despite owning a genuine copy of a Gen III game) and I wanted to transfer these Pokémon to my genuine Gen IV game. This is easier said than done, but thankfully did not involve any modifications to any genuine Nintendo equipment/games. Here's how I did it.
What you will need
- Two Game Boy Advance consoles. They can be bought on eBay for about £15-£20 these days. They generally don't come with batteries so you'll have to buy these separately.
- A Game Boy Advance link cable. I got mine off eBay for £4. You could probably do this with the wireless adapter too.
- An EZ-Flash IV miniSD. I got mine from flashlinker-shop.com for €39. This website also allows you to buy your memory cards and adapters on the same page.
- A memory card. It's probably best to get a microSD card these days, as it is the most supported. The 4GB version does not seem to be supported here so 2GB is the one to go for.
- Adapters for whichever card you choose. If you get a microSD card then you need a microSD-miniSD adapter. You might also need a miniSD-SD or a microSD-SD adapter. For this and the above item I got a pack from flashlinker-shop.com containing a microSD 2GB, a microSD-miniSD adapter and a microSD-SD adapter for €10. I'll be using this for the guide, but if you got something different then it shouldn't be too hard to modify.
- An SD card reader. I got one from flashlinker-shop.com for €5. I don't work for them honestly!! You might find that you have an SD card reader built into your laptop anyway so you wouldn't need this.
- Copies of the actual games you are going to be transferring to. To transfer off R/S/E ROMs you will need an R/S/E cart, and to transfer off FR/LG ROMs you will need an FR/LG cart. Or, if you have an existing cart with the National Dex unlocked then you could use that too across all 5 versions, but I didn't (the National Dex was unlocked on my ROMs but this isn't much help). I got the cartridges from eBay for about £15 each.
- The EZ4client software. Get the latest version free from here (compiled on 3rd April 2009). You'll need 7-Zip to extract it, which is also free software from 7-zip.org.
In total, all these things cost me about £115 or roughly $192. Not cheap but I was really committed to getting those Pokémon!
Setting up the cards
Open up all the packaging (yeah this took a while). Plug the microSD-miniSD adapter into the EZ-Flash IV itself. Plug the microSD-SD adapter into the SD card reader. Plug the SD card reader into your computer. Go to My Computer, right-click the memory card and select Format. Make sure you format it as normal FAT (not FAT32) and uncheck the "Quick Format" option.
Setting up the EZ-Flash IV
Extract the 7z file for the EZ4client software. Copy the file ezfla_up.bin from the EZ4client directory to the root of your newly formatted memory card (it should be the only thing on it). Remove the microSD card (safely using the taskbar icon) and put the microSD card into your EZ-Flash IV (using the adapter as placed before). Plug the EZ-Flash IV into one of your Game Boy Advance consoles (make sure the batteries are in). Hold down the R-Trigger as you turn the console on. Keep the R-Trigger held until you see the updating screen. Wait until the screen reaches 100% and the Star Wars logo appears. Turn off the power. Remove EZ-Flash IV from the console and the microSD card from the EZ-Flash IV.
Copying the games to the EZ-Flash IV
Put the microSD card back into your microSD-SD adapter which is connected to your computer through the SD card reader. Run the EZ4_client.exe in your EZ4client folder. Click Config and change the send path to the root of your microSD card. Click Open and open the first ROM you want to copy (.gba extension). Click Send. Repeat for each ROM you want to copy. Remove the microSD card.
Copying the save files to the EZ-Flash IV
Put the microSD card back into the EZ-Flash IV and plug that into the console, turn it on (without R-Trigger held down this time). Press A to close the message and then select the top-left icon on the screen. Press A to close the message and open your EZ-Disk. Open each ROM in turn to initialise the save files. Each time you open, you will have to wait until the processing bar reaches 100% and then get to the professor screen (Oak or Birch respectively). Turn off and switch the microSD card back to your computer (you should know how to do this by now). Open the SD card in My Computer and open the saver folder. Note the names of the .sav files in this directory. Now rename your save file you want to copy to this exact name (matching each save to its corresponding save from the same game, obviously) and copy the save file across to the SD card, overwriting what is already there. This is very important the names must be identical as the EZ-Flash IV recognises specific names. Remember to rename the copies on your computer back afterwards.
Initialising the real game cartridges
If you have a save file already on your game cartridges then you don't technically need to do this, but I prefer to start from a clean slate with these cartridges so that I can have more room in the boxes. Plug each game cartridge in turn in the console (you should only have a maximum of two: one out of R/S/E and one out of FR/LG), start a new game and get to the point where transfers are enabled. In R/S/E this occurs after speaking to May on Route 103 and then going back to visit Birch to get the Regional Dex. In FR/LG you will need to deliver the package from Viridian back to Oak in Pallet. Then save each game upstairs in the Pokémon Center. (Note as soon as you get upstairs, Teala will talk to you and you need to listen to everything she says before you can save.
Setting up for Pokémon transfer
Plug your microSD card into the EZ-Flash IV. Plug your EZ-Flash IV into the console. Connect this console to the other one with the link cable. Plug a cartridge into the other console: either R/S/E if you are going to be transferring from R/S/E or FR/LG if you are going to be transferring from FR/LG. Turn both consoles on.
Doing the Pokémon transfer
You will need to do this separately for each ROM you are transferring from. Open the ROM as before (from the top-left icon in EZ-Flash) and start up both games. Go to the Direct Corner and transfer the Pokémon as you would normally. If you are switching to another game of the same region then you just need to reset the console with EZ-Flash in afterwards and select a different ROM. If you are changing region (from an R/S/E to an FR/LG ROM) then you will need to turn off the other console as well and switch cartridges (unless you'd unlocked the National Dex).
Transferring to Gen IV
Optionally, you can now transfer from your genuine Gen III cartridges to Gen IV using a Nintendo DS Phat or a Nintendo DS Lite (not the DSi). You must have unlocked the National Dex in the Gen IV game. Just plug both the Gen III and the Gen IV games into your DS and transfer using Pal Park as normal.