Hey guys, im pretty new to these forums so ill post in here
Ive been reading around and I've noticed a few people have made som FF3 translation carts out of some donars for there NES. Ive been looking around and the information seems really fague so I have a few questions.
1: What kind of cart does the donar have to be? I've heard people say that you need an early super mario bros 2, with all 72 pins. But ive also heard people say you can do it with a super mario 3, gauntlet 2, or a few megaman carts. So what is it? I beleive the oringal ff3j was a tnrom mmc3 cart. Not sure what that means but I know you need to get a tnrom mmc3 cart to put the CHR and PRG on it. It also has to have a battery for save states, or the ability to wire a battery in one. Where would I find wiring diagrams for puttin a battery in on of these carts? And is any other wiring needed? I plan on using a super mario bros 3 cart, since I have two. As long as they work for this.
2: Whats a good rom to use? I know most emulators are "forgiving" unlike the NES and people usually program with that in mind, and if you program a cart with these files the NES can not run them. So I would need to find a translation that would be programmed well. also is there any test I could give a rom before I try to right it to flash/eprom memory to make sure it would work for NES? Some sort of true 6502 emulator?
3: What kind of flash chips would I need? I'll probably get 512 chips and just rewrite the images on the chips repeatidly until the entire 512k is taken up if ff3j is not already 512 k. What are good flash chips to use? How many pins should I be looking for in the flash chips? 32/28?
Im pretty handy with electronics. I could easily desolder/solder PRG.CHR chips to and from the board blindfolded probably. Ive had lots of practice so thats no obstical for me. But I am a newb to this programming and IC's in general so go easy on me. Please explain all you can in great detail and don't assume I know anything please!
Thanks in advance, Lung-Dart
lungdart wrote:
1: What kind of cart does the donar have to be?
Any MMC3 version should work. The thing that makes FF3 tricky is it uses 8k CHR-RAM, and most games use CHR-ROM.
For FF3 you'll need MMC3, 512k PRG, 8k CHR-RAM, and if you want to save, you'll also need a board with battery backed RAM.
Neither Gauntlet 2, SMB2 nor SMB3 fit the bill. Megaman 4 and 6 have the right PRG/CHR sizes, but the RAM on those carts isn't battery backed. You might be able to put a battery in, I'm not really sure. I kind of doubt it, but I don't really have any experience with this kind of thing.
That's about all I can really say. Hopefully someone else can come along and fill in some of the other gaps.
Okay, first off, I'm sure you can find the directions to use a SMB2 cart on google. Don't worry, I'm not saying "you're dumb, you should have used google", I'm just saying you can probably find that there. For EPROMs, you'd want a 27C040. I don't know anything about Flash, I have never used it in my life. I should though.
I'm just using my FF3j cart that I got for $8, so it's alot easier. And by the way, a 27C040 is 32 pins, just like the PRG chip for FF3j. It's going to be trickier for you, because you are probably going to be using a 28-pin maskrom cart, and it's going to have CHR-ROM, which FF3j doesn't have. FF3j has PRG only, and the graphics are embedded into the PRG, and stored via $2007. It's called CHR-RAM, really handy at times.
But yeah, you'll find some site with like a bunch of NES game characters on top dancing, like there's Simon Belmont, mario, megaman, and stuff. That has the directions for a Mario 2 cart to FF3j cart conversion. I think there's a link to it in one of the threads that I've been talking in about this.
And also, make sure you have a good translation that works in Nintendulator, because that's the most accurate emulator out there, and it's a pretty good chance it will work on the real NES if it works on that emulator.
Oooh... you mean you can swap out the PRG/CHR chips for different chips?
Like you can put a 512k PRG chip on the SMB2 board to make it big enough?
Gah... shows how much I know when it comes to hardware. =P
Well, I just know that you can do some rewiring to do that sort of thing. It looks really ugly though, and it looks like you could never ever make it back into a SMB2 cart once you make it an FF3j cart. I'd really just go with the FF3j cart to make an FF3e cart, if you can find one cheap like I did.
Don't worry, I'm just starting to learn about hardware, so I don't know much either.
Thanks for the replies.
I know you can interchange prg/chr chips with eprom's/flash. I would want to go flash however since Eproms (to my knowledge) can only be programmed once, and if you want to rewrite you have to erase them with UV exposer.
Celius: I saw your post and I do know what website your talking about. I was there for a few, but left pretty quick because of the animated background. I tried looking for the information I wanted but my eyes started to bleed. I forget what it was called but I could easily find it again. I saw there was diagrams on how to convert tgroms to tnroms or something which can make ff3 work on one of those carts. Didnt see anything on the battery building department.
Update: The webpage was called ROm laboratory. I disabled the background (thankgod) and may have found what I was looking for.
http://nintendoallstars.w.interia.pl/ro ... m2cram.htm This shows howto change a mmc3 chr rom cart to a chr ram cart, which you could then program the PRG with the ff3e rom after being tested with that NES emulator. you were mentioning earlier. I notice that most mmc3 chr rom carts do not have the center pins, and I think this is the soul reason people want the mario 2 cart with the center pins. I could more then likely make that pin. A little peice of tinfoil aluminim/metal sheilding or what ever epoxyd in place would do the trick. Who knows.
How would I go about making the battery though? How would that be hooked up, any info there? Also is there any other information I should be aware about?
Oh, I know that the Battery building process is there, because I've seen it. It's in one of the threads there, I know it. It's probably an older one though. It might not be for an FF3j cart, but it's for building an SRAM chip, at least.
lungdart wrote:
I know you can interchange prg/chr chips with eprom's/flash. I would want to go flash however since Eproms (to my knowledge) can only be programmed once, and if you want to rewrite you have to erase them with UV exposer.
Unless you're making a NROM devcard for test purpose, I really see no inconvenient here. Personally, if I made a home-made cart, it really is to never change the game that is inside again. I'd do it only with great games, since you can play good-but-not-so-great games in an emulator.
With a game like FF3 it may be worth the work to play it on your real console, but honnestly, why would you want to erase it ? That'd just be too stupid.
Bregalad wrote:
Unless you're making a NROM devcard for test purpose
Which the majority of us either do or wish we could do.
I only want to be able to erase it if it didnt work the first time. Im almost 90% sure the first flash wont work like I expect. so its better to be prepared then to be at a loss of a cart!
I found the battery thing on that site and I think I have the jist of doing this. First I would have desolder the CHR ROM from the MMC3 cart of my choice (im using Super mario bros 3), Then I get a 8kb (doesnt really matter on the size I dont immagine) VRAM chip. I then connect it according to the diagram on rom laboratory, (if its 28 pin, I assume if its a 32 pin chip you can just attach it pin for pin). Then I attach a 3v lithium ion battery like the CR2032, to the VCC/ground of the WRAM chip to keep power to it while the NES is off. so the save states don't get whiped. Then I have to get a translated ff3j rom from the internet and test it in nintendulator or what ever it was called to see if its compatible. Then I need to brake it up into its PRG and CHR, but since FF3 uses CHR RAM I assume it doesnt actually have a CHR part to the rom. So I just remove the header from the .nes file and then flash a PRG chip with it, plug it in the cart, and create my own pin #56, or just hardwire it to the NES board.
Does this all sound correct? Am I missing something? Is something wrong? Do I NEED the diode for the battery? If so I could just use an LED i have floating around, or do they not function as well as regular diodes for constraining reverse voltage?
Everyones been a big help, thanks!
Does this all sound correct?
I think if you do something wrong with your card, that isn't caused on the CHIP. You have almost no chance to damage the chip until it is soldered in, and if you do everything correct you should have no problems to not damage the card. Just MAKE SURE WHAT YOU'RE DOING !
You have no chance to programm the EPROM wrong or to write wrong data to it, even if it is your first time, unless you're really stupid. Programmers are surprisingly simple to use. Also, if your ROM works fine in Nintendulator, there is 99.84848484% chances it works fine in your real NES, once you removed the iNES header.
I wouldn't do the battery thing as it is on the background animated site. I've heard the battery was constantly powering the chip, even if the +5V voltage from the console is here, and that would cause the chip to have other pins have +5V voltage input, while the chip is powered at the battery voltage +3V and THAT IS BAD!!
You need some diode and resistor circuitry to handle that. I'm not sure what is on that site is exact.
NO, you CANNOT use LED as a standard diode, because it will make you loose too much voltage (~2V instad of ~0.7V), and not enough current is allowed to pass trough (most LEDs are max 20mA, while most common diodes can allow 500mA). I'm sure your RAM chip will consume less than 20mA when in backup mode, but in active mode that may not be enough.
Also, LEDs can support up to ~5V at reverse voltage without have any damage, while any diode can support 1000V usually.
You definitely should have 2 diodes.
One between the real VCC (+5V) and the fake VCC, that switches from +5V and +3V. Then, onother between the fake VCC and the battery + that is +3V.
Both cathodes should be on the RAM VCC pin, so, when +5V is here, the voltage go trough the diode, and the chip is powered by the real VCC. But the other diode would force the voltage not to reach the battery, to avoid forcing its voltage and make it explode or something.
Then, when the VCC disapears, the batter will power the RAM circuit, and the other diode will prevent it to power all the other chips of the cartridge, to avoid the battery weakens too fast.
You'd also needs resistors and maybe capacitors, I'm really unsure about it.
Ya I was thinking it was a little sketchy myself about leaving 3v going to the Vcc at all times. I couldn't see it causing +5 volts to the other pins. But +5 and +3 at the same time sounds bad. As far as I know TTL chips can only take 5volts, its the cmos chips that are forgiving.
I couldn't seein using two diodes to cut off one power source or the other. Maybe a PNP transistor or Relay would do the trick, but theres that few miliseconds where theres no power connected. If the saves are not lsot there, they are certainly going to be corrupt.
Many people have made ff3 carts from Supermario bros 3, and I don't see any other battery how-to out there so this must work. When I get all the parts I need to do this, I will be hooking up a battery. It's a must. If I do go with this diagram, I will let you know how it goes.
I cannot really see what's wrong with the two diodes stuff I submitted, but if you say it is wrong, I can trust you, because I really is not sure.
By comparing a Zelda card with a Kid Icarus card, Kid Icarus is also SNROM but without battery and 2 diodes and several resistors are lacking.
I've heard this problems can be solved with transistors, but I really have trouble to imaginate the shematics that would do that.
If you loose power for a few ms, I think a decently big capacity can easily fix that.