Donor with 2x DIP32 mask rom...questions re: TSOP40

Hey folks, long time lurker (here and on NA), first time poster. Apologies in advance if my use of the search function has failed me, but I have a couple of Qs I haven't been able to hammer out answers for.

I am incrementally working my way towards being able to produce a repro for myself. I have practiced manipulting the ROM file by adding IPS patchs as needed and removng the header. I am checking the files in Ucon64 and then running them in Bsnes in "accuracy mode".

I have successfully desoldered mask roms from snes pcb, and then solderd them back on...and the game boots! Woot!

Last night I popped open a LoRom donor, Tecmo Super Bowl, to practice a battery replacement and it is DIP32 AND has two mask roms...

Q1: Can I even use a TSOP40 -> DIP36 (type III) combo for this type of donor/game? Would I have to re-direct the 4 extra pins from the DIP36 board to the snes pcb, or they even used? If they aren't used, can I just cut them off?

Q2: If I CAN use TSOP method, and there are 2 mask rom on a donor PCB, do I just put the TSOP->DIP36 package in the "P0" mask rom holes and leave the other mask rom slot empty? Do I need to do any address line wiring, or will the game accept all the info it needs from the one chip, since it contains all the info and is presumably mapped correctly?

Q3: Are all LoRom games DIP32? I have about 9 LoRom donors (NBA, Tecmo "super" games, couple Emmit Smith football) and 15 HiRom donors (All NHL and Madden games) stockpiled. Are HiRom games typically DIP36, or does it really vary from game to game?

Q4: Can someone confirm this: Since HiRom 32 Mb games are (typically? Always?) DIP36 single mask rom games, is this the reason a TSOP40->DIP36 combo can be simply dropped in the mask rom slot and is good to go without rewiring...is this accurate?

I am starting with a HiROM 32 mb game b/c the two I most want to play are Terranigma and SD3.

Any help appreciated! Cheers! I have ordered chips and supplies and I am awaiting my PCBs for the TSOP40-to-Willem adapter. They shipped end of last week! Going to be using a GQ-4X.

Generally on this forum we discourage copyright infringement, even of games that have been commercially unavailable for twenty years. We usually recommend that people buy a Super Everdrive, sd2snes, or (were it still available) SNES Powerpak because they have a significant non-infringing use (namely, development of homebrew).

As such, I will only point out this:

32 pins
- 2 for power and ground
- 2 for control signals
- 8 for data bus
= 20 for address lines
2²⁰ = 1048576 bytes.

I understand, but hope someone will still help me as I have seen in other threads here, and on other boards.

I am fully aware that legally I am infringing on someone else's IP. However, since it cannot result in an economic loss for the original IP owner I have no moral qualms in building repros for myself. If I was trying to bootleg PS4 games or program an HD loader for PS4/XB1, I would run into a moral dilemma as I would then be denying the owner of the IP revenue to which they are entitled for their commercially viable work. That would be both legally and morally wrong.

I am not trying to be argumentative, just being honest about the fact that my desire to play awesome old games I never had access to on original hardware trumps any hesitation I have to exploit IP that is no longer commercially viable.

I will try to make sense of what you have provided me though, and thank you!

Square Enix loses what you would have paid to buy an authentic copy of a different Square Enix title through a modern console's download store.

(Aside: As long as the homebrew community continues to fail to produce a compelling Super NES game with comparable production values to Square Enix RPGs, these repro threads will likely continue.)

I am derailing my own help thread LOL...oh well. All my questions in first post still stand though, if someone is kind enough to share their insight.



That argument is predicated on the false assumption that an authentic copy of a current game from the same developer is an acceptable substitute for a spefic retro game I would like to play...and that just isn't true. There is no substitute for Bahamut Lagoon if I want to play Bahamut Lagoon. Since it isn't offered in English, today, in my region, via any medium, I don't believe an economic loss is taking place with respect to that intellectual property. I could play it on an emulator, easily, but that is still infringement on the IP I am sure. Since it is virtually the same infringement, I would like to play on original hardware if I can manage it through a labour of love.

Please be sure: SquareEnix and other devs (Blizzard, Grinding Gear Games to name two others) get my $$$ for their current titles on current systems that are released in my language and region. I am not a pirate. I own all of Square's North American RPGs (well, most of them!) and currently play FFXIV. I will be buying a copy of FFX/X-2 HD Remastered when it comes out

It would be awesome if the SNES homebrew scene started producing JRPGs of a calibre in line with the old classics, but I don't know if that would eliminate desire to experience some of the specific games never released in NA on authentic hardware...Bahamut, Treasure Hunter G, SD3, etc. Nostalgia is a powerful force. I am 30, gaming since I was 5, and painfully aware (since high school!) of some of the games we never received haha

Sorry dudes, I realize you probably get new people signing up and asking questions out of the blue. I've read through many old threads prior and seen all the pro/con arguments for repros. I probably just need to do more trial and error but I am an information junkie and probably read more theory than I need to before I get my hands dirty sometimes haha. Sorry if I came off as defensive last post, this is after all your community and I am not a nes developer. I am an accountant, and was only a good programmer in crappy high school classes lol.

I would still love some clarity though. PMs welcome too

When you want to make a reproduction, just make sure it's for you, and you either already own the game via another distribution method, or it's 100% unavailable. Being expensive isn't much of an excuse.

Regardless, when making a repro, you only need to concern yourself with 3 things for the donor:
1) HiRom or LoRom. Without making modifications to the cart, you can't boot games in a cart that doesn't match the addressing scheme of the ROM data.

2) SRAM. Make sure you have at least as much SRAM as the game requires. Some games require exactly the same amount.

3) Mask Rom Pins. These are either 32 or 36 pins. You can't use a 32 pin rom in a 36 pin cart without soldering the higher address lines to ground. Also, as lidnariq said, there is a hard limit of 1048576 bytes on 32 pins due to address limits. So 8 Megabit/1 Megabyte is the max per rom.

You might want to consider building a hirom and lorom development board with a ZIF socket, and modify it to accept your EPROMs.

Use Wasabi to byte swap your ROMs and you only have to swap pins 24 and 31 with each other.

Technically, no work whose copyright is owned by a publicly traded company is "100% unavailable". It just costs half the company's market cap. But I'll agree that $1.26 billion (source: SQNXF at Yahoo! Finance) for an English translation of Seiken Densetsu 3 is probably far too expensive for anyone reading this.