Introduction: Final Fantasy III NES/Famicom English Translation Reproduction Cartridge

This Instructable will explain how to essentially convert a copy of the Famicom (Japenese NES) version of Final Fantasy III to English (or language of your choice). The goal of this guide is to provide an easy to follow method of recreating this game without mutilating existing cartridges. Everything in this guide is reversible, and does not require destroying any precious antiques!

The most popular method of reproducing this particular game is by using Super Mario Bros. 2 as a 'donor cart' and adding a battery circuit. This method is a bit more tricky and somewhat destructive to existing cartridges. I find my method to be more 'original', though, since we're using an actual Final Fantasy 3 cartridge. If you're interested in trying the SMB2 method instead, I recommend this guide by Gorillazero on

Required skills:

  • Ability to read and follow instructions
  • Basic soldering skills. You don't have to be a surgical expert; these solder points are a decent size. With some patience, this could be your first time ever soldering and you could still pull this off. Don't be intimidated. Just practice on some broken electronics if you don't know what you're doing.
  • Patience!

Note: This guide is very detailed, and assumes you know nothing. If you already have a solid familiarity with EPROMs, you may find this particular guide to be far too wordy. If you're a total noob, you're in the right place.


  • Why do I need an EPROM? Can't I just reflash the chip that's already on the board with my programmer?
    • The chips on NES cartridges are Mask ROMs, meaning they are not erasable or reprogrammable. The contents of Mask ROMs are programmed on the chip at the time of manufacture, and can't be user-programmed.
  • Do I really need an EPROM eraser? Why can't I just write over my EPROM with a programmer?
    • EPROM stands for "Erasable Programmable Read-Only Memory", not to be confused with EEPROMs (Electronically Erasable Programmable Read-Only Memory). The ones we are using, with the single E, must be erased by UV light. EPROM programmers can only change zeroes to ones, NOT vice versa, so we need the UV source to change all of the bits to zeroes before we can write to it.
  • Can't I use sunlight or a blacklight to erase my EPROM?
    • Not really. Sunlight can technically erase an EPROM, but it would take several weeks of direct exposure. You need the right UV spectrum to do it efficiently.
  • Why do I need a 4k EPROM if the game is only 512 kilobytes?
    • EPROM storage is measured in "Kilobits", not "Kilobytes". There are 8 bits in a byte, so Final Fantasy 3 is actually 4,096 kilobits.
  • Will this work with other games?
    • Yes. The process for Final Fantasy 2 should be nearly identical, and this process can be followed for many other reproductions as well.
  • I'm a total noob but I really wanna try this out, should I?
    • Hell yeah.

Step 1: Here's What We Need...

So you're going to go through with it? Sweet! Here's a list of everything you'll need to create your translated Final Fantasy 3 cartridge, and where to get them:

  • Final Fantasy 3 for the Famicom: Ebay
  • A Famicom (60 pin) to NES (72 pin) adapter: Amazon, Ebay, or see if you already have one!
  • A 15-30W soldering iron: I really love my Antex C15, but any 15-30W iron from RadioShack, Walmart, Ebay, or Amazon will work just fine.
  • Solder (preferably thin): Ebay, Amazon, RadioShack, Walmart. Make sure to get the stuff that's for electronics, not plumbing!
  • A desoldering iron or desoldering bulb: Amazon, Ebay, RadioShack
  • A 27C4001 EPROM chip: Ebay, OR see if you can harvest one from old/broken electronics at home or work. I managed to find mine on a broken NFL Blitz arcade board that I had lying around.
  • A UV EPROM eraser OR a toothbrush, denture, or pacifier sanitizer: I used an iTouchless UV toothbrush sanitizer that I bought on Amazon for $16. You should also be able to find an actual EPROM eraser on Ebay or Amazon for around $20.
  • An EPROM programmer that can program 27C EPROMs: I used a Signstek Universal USB MiniPro EEPROM Flash BIOS Programmer from Amazon, but others from Ebay should work just as well.
  • Small flat-head screwdriver: Your toolbox, pretty much any store ever, Amazon, etc...
  • A foot or two of thin wire: RadioShack, your closet, a broken ethernet cable, etc etc...
  • An empty NES cartridge: Amazon, Ebay, etc; can be purchased already empty so you don't have to destroy an existing game. Mine came with the adapter I bought on Amazon.

Step 2: Preparing the Translated Game ROM

First we need to understand how NES ROMs work. Inside a standard .NES file are binaries from two mask ROM chips commonly found on NES cartridges: The PRG and the CHR chips. In the case of Final Fantasy 3, the CHR chip is just used as RAM and therefore does not need to be flashed.

So now that we understand that, we need to get a hold of a copy of a Japanese Final Fantasy 3 ROM. This part I can't tell you how to do, but I assume if you're interested in classic gaming then you probably know how to find NES ROMs. You aren't really breaking any laws since you own a copy of the game. (Make sure you get Final Fantasy 3 for NES and not SNES as they are NOT the same game, but do have the same name)

Now we need to patch the ROM with the translation of our choosing. The best English one, by far, is this one by Alex W Jackson, Neil Corlett, and SoM2Freak. Other languages are also available in the Translations section of

Once you have the ROM and the IPS patch, you need to apply the patch to the ROM. There are lots of IPS patchers over on for various operating systems; Personally I use IPS-Win. Patch the ROM as shown in image #1 in this step, then test it in an emulator such as fceux and make sure it runs properly.

Once we have a properly patched ROM in the desired language, we need to split the .NES file into its respective PRG & CHR files. For this, I use a program called NES Mapper Reader, also available from Open NES Mapper Reader, goto File - Load ROM, and navigate to your translated FF3 .NES file. As seen in image #2 of this step, click "Analyze ROM", then Check the "Remove 16 byte NES Header", "Output CHR/PRG", and "Auto Split CHR/PRG" options; click Prep. FOR SOME REASON, this step always errors; however, it worked just fine, trust me.

You'll be left with a 512k PRG file and a 0k CHR file. The PRG file is the one we need, so set it aside.

Step 3: Preparing the EPROM

Next we need to erase our 27C4001 EPROM. As you can see on your EPROM, there is a small quartz window in the center of the chip where you can see the EPROM die. This is because the only way to erase EPROMs is by exposing the die to a low spectrum of UV light. For this, we can either use a proper EPROM eraser, OR you can do as I did and use a cheap toothbrush sanitizer (pacifier, denture, or mouth-guard sanitizers should work too).

If using a normal EPROM eraser, just place the chip in the drawer with the window facing up and run it through a cycle or two (~15 minutes or so). If you're going my route and using a toothbrush sanitizer, place the chip right next to the bulb with the window facing the bulb, then 'tent' it in aluminum foil as seen in the photos of this step. Once you've got it secured, run it through 3-4 cleaning cycles (~7 minutes each).

Once the EPROM has been exposed to UV light, go ahead and check it with your EPROM programmer. Place the chip in your programmer, ensuring the notch is facing the right way. The software of your programmer should have a "Blank check" or "Blank test" feature that will confirm that the chip has been completely zeroed out. If it errors, just place the chip back in the eraser for another couple of cycles until it passes the test.

After the EPROM blank test passes, you're ready to burn your translated PRG binary to it. Load up the PRG file you created in Step 2 and Program it! Your software will typically have a "Verify" option as well, which I recommend selecting. Once the verification confirms it programmed properly, the EPROM is good to go.

Step 4: Open Up the Famicom Cartridge

Time to get cracking on the cart!

Ok, so I'm not gonna lie. I busted a couple of the clips on my FF3 cart when I was opening it; it's kind of a pain. There are no screws in Famicom cartridges, only plastic clips. As the plastic gets old, it gets very stiff and brittle and breaks easily. I just poked at mine with a small flathead to try to loosen the tabs on the inside, and ended up snapping the inside tabs off. Honestly, I found the tabs at the top to be sufficient to hold the cart together, so busting a couple of tiny interior tabs didn't matter much.

If you really want to avoid damaging the inside of the cartridge at all, I suggest Googling some tips on how to safely open the cartridge.

Step 5: Desoldering the PRG Chip

Ok, so you've got the FF3 PCB out and you're looking at a battery and 4 chips. The two chips on the bottom of the PCB are the CHR and PRG chips we mentioned in Step 2. The PRG chip on the bottom right is the one we need to remove.

So, here you have options. Some people take the 'easy' route and just snip the legs off the PRG chip and then clean out the holes. To me this is gross and messy, and ends up ruining the original chip which I'm not a fan of. If you wanna be a scrub you can do that, but if you wanna do it right, use a desoldering iron like the one I showed in step one. Flip over the PCB and locate the 32 pins on the reverse side of the PRG chip. One at a time, heat the pins with the hot end of the iron and squeeze the bulb. If done correctly, all of the solder holding the pin in place will be sucked into the bulb. Do this 31 more times, clearing out the bulb every few. If you're a rookie, feel free to practice this on a broken PCB you have lying around.

Once you've got all 32 pins desoldered, it should look like mine does in the second image of this step. To ensure all 32 pins are properly freed, poke at each of them individually with a small flathead screwdriver or fingernail to make sure it's able to wiggle a bit. If it doesn't budge, you may have a small amount of solder left in there. Desoldering irons don't work well on small bits of solder, so you may have to resolder the pin and then desolder it again if it's stuck. Squeeze that bulb with authority and willpower.

Once you're sure all pins are freed, flip the board back over and remove the chip. Unless you have a legit IC puller, just slide a flathead screwdriver underneath until the chip starts to come free. Once you've got one half of it up, slide the screwdriver in from the other side until you can pull out the chip. After that, your board should look like image #3 of this step.

Step 6: Installing the EPROM

Now you might think the next step is obvious... Just put the EPROM into place and solder it in and we're done, right? Well, not exactly. On the 32 pin ROM chips, Nintendo slightly changed the pinout from the standard 32 pin EPROM pinout. Because of this, we need to rewire our 27C4001 EPROM a little bit so it matches that of Nintendo's. Don't worry, it's not that difficult.

This is the part where some guides will mention "cutting tracks". My guide focuses on keeping the game intact, so we're going to avoid that by simply lifting pins on the EPROM. Start by bending up pins 1, 2, 24, 30, and 31 on your EPROM. Use image #1 as a guide to which pin is which. After you've bent the pins up, you can place the EPROM into the empty PRG slot. Triple check that you bent the correct pins and solder it in. All non-bent legs need to be soldered into place. With the back side of the PCB facing you, just heat the metal around each hole with the tip of the iron, and feed it a small amount of solder. Don't use too much or it will bleed through to the other side and potentially short out other pins.

Next we need to run the following wires from the bent legs to the empty holes:

Pin 2 to hole 24

Pin 24 to pin 16 (GND)

Pin 30 to hole 1

Pin 31 to hole 2

Image #2 in this step is an awesome visual of this, which Gorillazero from made.

You can go about this one of two ways. The first method, which is what I did as you can see in Image #3 and #4, is to run the wires directly into the empty holes and solder them in as if they were IC legs. I find this to be the cleanest method, but it can be sort of a pain to get it all in place properly. Alternatively, you can run the wires around and behind the board and solder them to the holes from the back.

Step 7: Testing the PCB

If you've made it this far, you're basically done! Your game should actually be functional at this point.

Before putting this into a cartridge, let's make sure it works. Plug your finished game PCB into your Famicom -> NES adapter, and stick it in the NES! This is a lot easier with a top loader than it is with a front loader, but it can be done with either. Make sure your chips are on the side of the adapter labeled "NES CART LABEL SIDE" and keep that side facing up (or facing front in a top loader).

Now turn the NES on and in a perfect world, you'll see a blue screen with English text! Hit start to make a new game. If you're lucky like me, the save data leftover from whatever Japanese kid owned the game last may amazingly still be in tact. Who knew a CR2032 battery could last 30+ yuears

If the game isn't working, remember, this is still a Nintendo game and as finicky as they've always been. Make sure it's in the console properly, the pins are clean, etc etc. If you absolutely can't get it working and you're certain your NES is clean and functional, you may need to double check your solder job and make sure nothing is shorted and that your rewiring is correct.

Step 8: Assembling the Cartridge

Our final step is to house the PCB in a cartridge.

You've got a few options here. If you're using the small NES to Famicom converter PCB like I am (Image #1), you'll need to house this in an empty NES cartridge as it won't fit back in its original Famicom cartridge with the adapter attached. Image 2 & 3 of this step show how that's done with a standard 3 screw NES cartridge shell. Once you've got it in the shell, screw it down and print out some custom artwork for it if desired! Buy some sticky paper and use this template, or find a premade one online. If anyone has any custom artwork they made and want to share, feel free to drop a link to it in the comments and I'll add a link to it.

Alternatively, if you want to retain the original FF3 Famicom case, you can use an adapter like this instead. This is a lot more expensive, but with this you can use the same adapter with multiple Famicom games. This would come in handy if you decide to repeat this process with Final Fantasy 2 as well.

Lastly, if you already own a Japanese Famicom, then you don't need an adapter and can put the PCB back in its original cartridge shell.

Leave comments with any questions, feedback, or success stories!


This game is actually pretty awesome, so I recommend playing it all the way through!

Congrats on your project if you made it this far!

Keep the original PRG chip in a safe place and you can swap it back if you ever want to return the cartridge to stock. You know, in case a tragic natural disaster somehow destroys every cartridge except yours and you want to sell it for 50 grand on Ebay.

First Time Author Contest 2016

Participated in the
First Time Author Contest 2016