Hardware:
Software:
Before you attempt anything you must first make sure that you have access to an EPROM burner and eraser. Most colleges have an electronics lab with an EPROM burner in them. You need to make sure that it supports 2megabit EPROMs. Buying an EPROM burner can be expensive, but I've seen cheap ones available that will work perfectly for this project for a decent price, go here:
UST Research, INC.
Or can also build an EPROM burner yourself fairly cheaply. Go here:
ZWS.COM EPROMR 2 Programmer for more info.
You can buy a 2megabit EPROM from Jameco or JDR Electronics, (search for 27c2001 or 27c020). Make sure you get DIP style. The NES doesn't need fast EPROMs either, anything faster than 200ns should work fine. Most of the time EPROMs come blank when you buy them, but I've had a few that were refurbished and were not blank. You can check to see if its blank with the EPROM programmer and verify, if not you'll need to use a EPROM eraser. NO, you cannot erase EPROMs with a normal black light. I've never tried it in the sun, but i hear it takes weeks and could possible damage your EPROM. You need a real EPROM eraser or you can build one.
You will need a Game bit to take most NES carts apart unless they are old enough that they normal screws.
Take the cart apart and remove the PC board with the chips on it.
Now we can start the fun part, desoldering the old rom chip out. Be careful not to press against the copper strips on the PC board you may dislodge them.
You should take a small pair of pliers and wiggle each pin and loosen them a little so you won't damage any of the pin holes when you remove the chip. Take a small flat screwdriver and carefully pry the old chip up on each side, if it doesn't want to move, go back and double check that you've desoldered most of the pins. Make sure you look at the pins from the top, not just the bottom, to make sure the pins are free and not soldered in.
Once you desolder the chip, it should look like this:
From the back side should look like this:
Now we need to patch the rom image before we burn the FF2E rom image to the EPROM.
First you'll need to get a copy of the Final Fantasy 2j rom floating around the internet. Next, patch it with Neo Demiforce's 1.03 English patch. In this case the name of the FF2j rom is "ff2.nes".
You need to run the command:
ucon64 -i ff2.nes --file=ff2eines.ips
It should look something like this:
Then we must patch it with my patch to fix the UNROM/MMC1 problem. So you should have downloaded my patch fix from above. Run the following command:
ucon64 -i ff2.nes --file=ff2emmc1.ips
Again, it should look similar to this:
We need to strip the NES header and footer (sometimes there is one) now run UCON64 again with the following parameters.
ucon64 -s ff2.nes
It should display something like this:
Now we have FF2.PRG which is our binary file to burn to EPROM. Some EPROM programmer software will not accept the file unless it has a .BIN or .ROM extension, so you might have to rename it. Load up your eprom burning software and burn this file to your 2megabit (27c020) EPROM. Verify (read back) the file and double check it was burner correct with your eprom software, most burners will do this automatically. Make sure you don't put it in backwards! Remember the notch is where pins 1 and 32 are.
Burning the EPROM chip:
Now we need to cut tracks to pin holes 1, 2, 22, 24, and 30. Looking at the top of the PC board, cut the tracks to pins 1 and 22, use this picture as a guide:
Next cut tracks to pin holes 2, 24 and 30. Note: Do NOT cut track 22 on the bottom side.
Next thing you'll need to decide is if your going to use an IC socket or not. If you use a socket, you can play different games with your modded cartridge, like any SGROM style games too (like Megaman2 or Defender of the Crown). But most games will erase the WRAM backed by the battery, so be warned, you will probably loose your Final Fantasy saves.
For those that are using IC sockets, you will need to cut a hole in the plastic NES cart container where the ERPOM chip is, so it can stick out. You will also need to remove the metal bar in the NES so you can slide the cartridge in.
Double check your work and make sure that you cut the correct tracks. Put the EPROM or IC socket in place and solder all the pins in. Now, you'll need to solder the wires in place. You will need to solder 4 wires. (Note that pins 1, 32 and 31 should all be connected to +5V)
See this picture for reference on soldering the wires:
Reassemble the cartridge and now your ready to go! If it doesn't work the first time, try resetting a couple times and powering off. If it still doesn't work, check all your connections using a volt/ohm meter.
A common problem is that dirty and dust get on the connectors, so you should get some alcohal or paint thinner use a rag and clean the edge connectors. If you can, find an NES cleaning cart and clean the actually NES.
If it still doesn't work double check all your soldering connections, and that you soldered them to the right places. For those that used IC sockets make sure that you firmly press the EPROM down into place, and that the EPROM is also correctly positioned.
Here are some screenshots from my TV of the game in play:
Email me for questions/problems