FFIV cart done! - Anyone familiar with custom SNES carts?

[rCadeGaming]

I'm looking to play fan translations of Final Fantasy IV and V on my actual Super Nintendo. I already have the roms and translation patches, and Super Famicom carts of both of these are pretty cheap on eBay.

I've heard of needing specific donor carts for creating customs, as well as having to replace the ROM chips. If I bought the original Super Famicom carts of these exact games, could I just use the existing chips inside? Could I just desolder, erase with an EPROM eraser, program in the translated ROM with an EPROM programmer, and solder them back in?

Anyone have any ideas? I know erasers and programmers aren't super cheap, but it would be fun to get into, and I've been quoted some pretty high prices for custom SNES cart services.

[Op Intensify]

There are SNES flashcarts out there. The only one I know of is the Superufo, which comes with an adapter for Super Famicoms.

[shmuppyLove]

Original games probably don't use EPROMS?

But as previously mentioned, a flash cart is probably the easiest way to go.

Unfortunately they ain't cheap.

Edit: Link fail. Hey what's that "Preview" button for anyway?

[rCadeGaming]

Yes, I realize this. I'm looking at an Everdrive. From a collection standpoint, this isn't nearly as nice though. A dedicated FFV cart in the original shell with an original label would be great. It'd also be fun to make. Also the equipment may be around the same cost as a flash cart.

Oh, and I don't have a Super Famicom, just a US (NTSC-U) Super Nintendo. It was modded to play Super Famicom cartridges (extremely easy). I currently have a Super Famicom cart of Hagane which works great. It was $40 on eBay, versus hundreds for a US cart.

-

Original games probably don't use EPROMS?

Yeah, that would make sense.

I just found this site:

http://nintendoallstars.w.interia.pl/romlab/sneslab.htm

Anyone have any advice?

[BIL]

This topic might help a little (concerns creating a custom Seiken Densetsu 3 translated cart).

[rCadeGaming]

After more reading, it looks like carts originally have non-programmable ROM chips. These must be replaced with the reprogramable EPROM's. Also the EPROM's have a bit of a different pinout, so you have to cut and rewire some PCB traces to get anything lining up.

So my questions are:

1. Could I use the FFIV and FFV Super Famicom carts?
2. How will I know exactly what kind of EPROM chip(s) to get for this specific game, and how exactly to modify the pinout?
3. Would if have to do anything besides swapping the ROM/EPROM chips and fixing the pinout?
4. What kind of EPROM programmer is recommend? Willem's are supposed to be cheap, but adequate. TOP853's are very cheap on eBay.

[mrsmiley381]

I researched this a few years back and even have a few reproductions from someone. Here's the deal:

1. So long as FFIV and FFV used the same mappers across both regions, yes. Odds are that they did.
2. You'll probably need a total of four (six?) EPROM chips per cart, where both originally had two. The problem is that the only EPROM chips I know that will fit in Super Nintendo games will not hold enough data; the solution was to put one chip in and then solder each of those legs to another chip and each of its legs. The result is that you have a shit ton of tiny wires leading to a chip dangling at the top of the cartridge. Unless you can now acquire chips with the right number of pins and increased storage, the same likely still applies.
3. A lot of wiring between extra chips, most likely.
4. Everyone I ever saw used Willem. Maybe shell out for a nicer one and make some other carts, like Blade Buster for the NES. Maybe do a Genesis repro while you're at it.

Again, I don't have exact chip numbers and I'm working off some old data from an old memory. I'll see if I can have my buddy bring his SNES screw bit over on Monday. If he does I can snap a few shots and explain what I'm trying to say, but with pretty pictures.

[Fudoh]

I've done quite some translation customs carts in the past....

(1) SNES doesn't have the variety of mappers the NES had. Basically the only important thing is to check wether you donor board is a lo-rom or a hi-rom board, since they require different recabling due to different pinouts.

(2) FFIV and V are rather small. I don't think that you need more Eeproms than the number of maskroms inside the originals. Compatible Eeproms with 8mbit (e.g. 27C080) are easily available and I would suspect that you need 2 each for each cart.

(4) I used a Batronix USB programmer for all Eeproms I've ever written.

[rCadeGaming]

I just picked up FF IV, V, and VI for Super Famicom for under $20 on eBay. Now to do some more reading and choose a programmer.

Basically the only important thing is to check wether you donor board is a lo-rom or a hi-rom board, since they require different recabling due to different pinouts.

How is this determined?

Also, do EPROM chips come ready to program? Is an eraser only needed to reuse them again after programming?

[Fudoh]

How is this determined?

Use these two pinouts (top is epprom/maskrom, bottom is cartridge connector)

http://pms.hazard-city.de/pinout.tif
http://pms.hazard-city.de/snesconn.tif

And just trace one of the lines, e.g. A18. It doesn't matter if use a lo- or hi-rom board. Just the recabling from the Eeprom is slightly different in the one case.

Also, do EPROM chips come ready to program? Is an eraser only needed to reuse them again after programming?

if you buy new Eeproms they're empty, yes. And even if you go for used ones, just buy freshly erased ones.

[rCadeGaming]

I think I'll be buying a Top853 on eBay, as they're extremely cheap. A lot of people have said they're not the best, but they're fine for what I'm doing.

These have a 40 pin socket. Does anyone know if you need an adapter for 32 pin chips?

[Fudoh]

No, usually not, just make sure pin 1 of the Eeprom goes into Pin 1 of the burner. Same for SNES carts. If you use a sac cart which uses 36 pin maskroms and you want to replace it with a 32pin eeprom, just make sure to allign the rom properly to Pin1...

[rCadeGaming]

Thanks. With a little more research i might be playing FFIV pretty soon.

[rCadeGaming]

Ok, I've been looking at EPROM's. This website looks to be a good place to buy new ones:

http://www.futurlec.com/ICEPROM.shtml

However the way it lists the size they'll hold is confusing. For example it lists a 27C040 as being able to hold 4,096kb because "512kb x 8 mbit = 4096kb." This is totally wrong, correct? From reading everywhere else, it looks like a 27C040 will hold a 512kb rom and nothing more, correct?

Additionally, what is the meaning of the different ns "ratings" of the chips? For example, there are four variations of the 27C040, 80ns, 100ns, 120ns, and 150ns. Is this the read or write speed of the chips in nanoseconds? How do I determine which one I need?

-

I've been working with the FFIV rom. I removed the header, patched it with a translation and cosmetic changes patch ("Cosmetic Changes 2"), and patched it with "Long Range bug fix" patch, which makes it somewhat larger. The original rom could be split into -two part files of 512kb each-, whereas the patched rom can be split into either -three of 512kb- or -one of 1024kb and one of 512kb-

Assuming that the original FFIV cart does have 2 mask roms (in the mail right now), could I simply burn the 1024kb part file to a 27C080 and the 512kb one to a 27C040, install them in place of the original mask roms (adjusting for pinout of course), and not deal with an address decoder?

Will this work? Will the SNES be able to find things in the right place when the ROMs are two different sizes and one of them is not the original size? Is there anything else I have to do?

[trap15]

The way they're labeling it is in K, not KB. K is kilobits, KB is kilobytes. 512K * 8 bits is indeed 4096K (and 4M), which is 512KB. So yes, they're correct, and so are you

ns is access speed in nanoseconds, yes. You can probably get away with the slower ones, but if you want to be safe, get the 80ns ones.

I'm thinking that you may have applied to "Long Range bug fix" incorrectly, or the patch itself is broken. You probably won't be able to adjust things properly in the cart if it requires a larger ROM.

[rCadeGaming]

So yes, they're correct, and so are you

Lol, ok I understand now. I guess I incorrectly assumed K meant kilobytes for some reason.

Edit: It looks like they were wrote kB where it should say k and vice versa. "4096kB (512k x 8 )"

Edit: Had to put that space above between the 8 and the ), or it became a ...

I'm thinking that you may have applied to "Long Range bug fix" incorrectly, or the patch itself is broken.

I think you might have been confused by my loose wording there. The Cosmetic Changes 2 translation/hack is what made the ROM larger. The Long Range Fix made no difference in size, as you would expect.


That being said what did you mean by this?

You probably won't be able to adjust things properly in the cart if it requires a larger ROM.

People make carts using translation hacks which make the ROM larger all the time, don't they?

[trap15]

I was under the impression that they didn't expand the ROMs. I may be wrong, but it seems odd that it would, considering the original cart probably wouldn't work in that case (I think? I don't know too much about SNES actually). Reading the above posts, if you just wire some stuff up differently it could work, but I don't know.

[Ex-Cyber]

IIRC, "FastROM" games used 120ns ROM, and the actual cycle time is closer to 140ns (which gives you a bit of headroom for MAD-1 propagation delay or whatever).

[rCadeGaming]

Does that mean I need to match that, or can go faster to be safe?

100ns chips seem to be common, especially in other sizes that don't have as many options.

[Ex-Cyber]

Yes, going faster is fine.

[rCadeGaming]

So... I got my SFC carts in the mail a few days ago.

FFVI has 3 Mask ROM's and a 74LS169 on it already. That one will be easy, looks like all I have to do is replace the chips with 27C080's and account for the Mask ROM pinout differences.

The strange thing is that IV and V also have 74LS169's, and they're single Mask ROM carts, which is confusing. V doesn't even have a MAD-1!

[rCadeGaming]

YEEEEEEEEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAHHHHHH!!! F*** YEAH!

Sorry, having a nerdgasm. I finished the FFIV cart today! And it works!

That one didn't have a MAD-1 either, but after a lot of studying on the MASK rom, cartridge connector, and 74LS139 pinouts, it made sense. I just had to cut some traces and reroute them to compensate for the pinout differences on the 27C801's, and solder them on. I put one in the original spot and one soldered to it's pins on the back side, and connected them to the appropriate pins on the 74LS139.

Unfortunately I don't have my camera on hand, but should have it back by the end of the day. I'll add some pics if anyone's interested.

I went with the TOP853 because it was cheap, and supposedly is just fine for what I'm doing. I was worried whether it burned the EPROM's right, since the software is crappy and it doesn't give you much information, but once I soldered it all up, the game seems to run fine.

The only problem that I've noticed is a flickery, stray white pixel, sticking out to the left on the right side of the white border for text boxes, near the bottom right corner. It always appears on the text boxes when you're talking to someone, not the ones in battle or the x menu or anything.

I don't know if it's a problem with the way the text translation works, if I got something too hot while soldering the EPROM's onto the cart, or if it has to do with the SCART to component transcoder I'm using (haven't had any other problems with it though). Anyone have any ideas?

Other than that it works pretty good from what I've seen, only played it for about half an hour though. Currently playing Final Fantasy Adventure on the big brick Game Boy, so I'll play through IV on this cart once I'm done that. I'll try something different than the SCART to component transcoder to see if I can rule that out.