MMC1 questions

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thefox
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Re: MMC1 questions

Post by thefox »

DRW wrote:So, isn't WRAM and a battery also a total waste here, but they still used it?
The cartridge Zelda is an FDS conversion. FDS has that 8 KB extra RAM built in.
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Re: MMC1 questions

Post by DRW »

Yeah, but when they converted it to cartridge form, they still opted for a battery and not for a password system like in "Metroid". And I'd like to know: Was it necessary because the additional 8 KB are really used extensively? Or could they have converted it to a password system, but they just said "Eh, screw it"?
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Re: MMC1 questions

Post by tokumaru »

DRW wrote:Even though my cartridges will be built from all-new parts, I only do games that could be easily reproduces with donor cartridges of widely available games.
Adding a battery without address decoding logic (as would be the case for CHR-RAM) is probably much easier than desoldering mask ROMs and replacing them them with rewired Flash/EPROMs, which people using donors would have to do anyway.
UNROM with 256 KB would be out of the question or at least I would do this only very, very reluctantly. How many copies of "Paperboy 2" or "Best of the Best - Championship Karate" exist out there? 20? 30?
You don't need any of these "rare" games, since the UNROM 128 boards already have all the hardware to support 256KB, they just left one of the address lines disconnected. With a little rewiring, any UNROM 128 can become an UOROM. This was one of my first hardware projects (unfortunately the pics are gone, but I still have the board somewhere, so I could grab new ones): viewtopic.php?f=9&t=2849

So yeah, there's absolutely nothing hard or obscure about battery-backed CHR-RAM or UOROM, as these are some of the simplest mods one can do to donor cartridges, even simpler than the mandatory ROM replacement. If someone has the skill to swap ROMs, they can add a battery or connect the extra address line of UOROM just fine.

But if you're so hung up on using "popular" configurations from back in the day, that's fine. I'm just trying to debunk the myth that some of the less common configurations make the production of carts harder or more expensive. In fact, the games you often mention as examples of battery-backed MMC1 games are crazy expensive, and would never be used as donors, so I don't know how easy it is to come by a reasonable MMC1 donor, so modifying an UNROM might actually be easier/cheaper. IDK.
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Re: MMC1 questions

Post by DRW »

It's more a thing that I do on principle: There were no battery-backed UNROM games or UNROM games with 512 KB, so I will not use them. It's not so much about actual practical doability since the games will be manufactured with new boards anyway.

When I create an NES game, I always imagine when this game would have come out if we were an actual 80s video game company in an alternate history.

"City Trouble" is supposed to be a game from 1986 that we worked on after discovering the NES in New York of 1985. I could have easily let my artist create modern-looking graphics, but I consciously opted for launch title aesthetics.

The new adventure game uses a gameplay similar to "Zelda", but with a real in-game story like in "Final Fantasy Adventure". So, I will not use anything that didn't exist in 1991/1992.

If I ever do my "A Nightmare on Elm Street" game based on the 1984 movie, it will be a simple game again.
(Since "City Trouble" is established to be our first game when we discovered the NES and it is already from 1986, I will probably create a backstory for the "Nightmare" game where we were working on an arcade game for another company in 1984, but the company went broke and the game never came out. So, after we set a foot in the market with "City Trouble", I ported my own, never-released arcade game to the NES.)

If I ever created an NES game based on "Django Unchained", I would be free to use modern mappers since the game would also be modern inside that fictitious history.
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Re: MMC1 questions

Post by DRW »

tokumaru wrote:In fact, the games you often mention as examples of battery-backed MMC1 games are crazy expensive
I don't know how you define crazy expensive, but "Final Fantasy" can be bought for $20-$40 on eBay. Surely not suited for mass-production, but still reasonable if the game is not available anymore and someone wants to get a reproduction of it.
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Re: MMC1 questions

Post by Bregalad »

DRW wrote:It's more a thing that I do on principle: There were no battery-backed UNROM games or UNROM games with 512 KB, so I will not use them. It's not so much about actual practical doability since the games will be manufactured with new boards anyway.

When I create an NES game, I always imagine when this game would have come out if we were an actual 80s video game company in an alternate history.
Ah, finally someone who understands me and have the same philosophy as I ! I've always come with that philosophy, make games as they were made back then, and I do not aim to push the system to its limit or invent new things. Whether this is feasible in hardware easily or not is a totally orthogonal question.

That's why I find it even weirder you don't insist more on passwords. Games with battery back up were really a small minority of games back then. I suspect that actually WRAM was not really more expensive as of 1988 or so, but batteries sill were expensive, and that up until the end of the console's life. The fact many games had to use CHR-RAM means Nintendo had to buy 8k SRAM chips in mass quantity anyway, so if games also used for PRG-RAM it doesn't make such a difference, just a minor cost increase. That's why it's common to see games that said "screw it" and added a 8k SRAM chip in the cartridge, probably it was only a minor cost addition to the cartridge, however only games that needed really complex saving system used battery backup.

That explains why CHR-RAM battery backup wasn't done; In theory it sounds nice, it's just a battery added to a normal game cartridge and does not require any extra chips (just extra discrete parts). But the problem is not the cost of the extra 8k SRAM chip, nor the extra PCB area, but the problem is indeed the cost of the battery which is very significant and cannot be reduced.

I suspect EEPROM saving was even more expensive, considering it was only used in a couple of games in Japan made by Bandai.

In addition to that, Passwords has the advantages you can write them down on a sheet and re-use them as many times as you'd like, unlike battery saves which are gone as soon as you overwrite them with another battery save. Even if you dedicate the whole 8k chip to saves you could have more save slots, but there's still a limited amount of them. Also loosing saves is a real problems. I've lost my saves regularly no matter whether I pressed RESET or not. When I did a whole playthrough of Final Fantasy 3 on real hardware, I usually saved to all 3 of the save slots to ensure at least one of them would remain on the next booting session. It was not rare than the first or the second save slot were randomly erased, only the 3rd one seemed more stable.
Or could they have converted it to a password system, but they just said "Eh, screw it"?
To be honest, for me it's still a mystery to me why Zelda used battery saves when Metroid and Kid Icarus, using the same game engine, didn't. My wild guess is that selling Zelda more expensive was more acceptable because it came with a gold package (except some later revisions) and came with a walkthrough included.
Does "The Legend of Zelda" or "Final Fantasy" use that enable/disable feature anywhere?
I can't comment on "The Legend of Zelda" (you should look it up using FCEUX), but I can guarantee you Final Fantasy does not use the WRAM disable bits, at least not directly. The CHR-banking regs are just written to with "00000" at startup, which enable SRAM. It's possible that it's disabled at power-on if the MMC1 internally initialize to "11111". All PRG bankswitching is done with the top bit at "0", which means again that SRAM is enabled (and again, it is likely that the MMC1 defaults to "1" effectively disabling SRAM at power-on).

Actually I'd be very interested to know if/which games ever used those bits other than setting them to "0" at start-up and never chanting them ever again.
I don't know how you define crazy expensive, but "Final Fantasy" can be bought for $20-$40 on eBay.
Both "The Legend of Zelda" and "Final Fantasy" are well known because of their franchise. I'd expect SNROM games which aren't part of a well known franchise to be significantly cheaper (and also, in some cases, less shameful to destroy).
Using CHR space for things other than tiles isn't so rare though. SMB and a bunch of CNROM games have data stored where tiles would normally be, so I guess developers weren't opposed to sacrificing a few tiles.
But this is with CHR-ROM, which is a completely different thing than CHR-RAM.
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Re: MMC1 questions

Post by tokumaru »

Bregalad wrote:But this is with CHR-ROM, which is a completely different thing than CHR-RAM.
Of course, these are totally different scenarios, but both involve the sacrifice of a few pattern table slots that can't be used for graphics anymore.
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Re: MMC1 questions

Post by tepples »

DRW wrote:UNROM with 128 KB is fine since there are countless games like that.

UNROM with 256 KB would be out of the question or at least I would do this only very, very reluctantly. How many copies of "Paperboy 2" or "Best of the Best - Championship Karate" exist out there? 20? 30?
Converting UNROM to UOROM isn't significantly more complicated than the rewiring needed to use UVEPROM or flash memory in the first place: three wires to route D3 through the '161 and the '32 to PRG ROM A17. But dead-bugging a WRAM onto a donor would be a job.
DRW wrote:MMC1 with 256 KB is already acceptable because of "Final Fantasy" alone, a hugely successful game, but I assume there are more games with this mapper and this ROM size.
NesCartDB's list of 2 Mbit MMC1 games with 64 kbit CHR RAM and WRAM with battery shows about 50 games, mostly Japan-only, but including Destiny of an Emperor, Dragon Warrior II, Final Fantasy, Genghis Khan, AD&D: Hillsfar, Maniac Mansion, NES Open Tournament Golf, Nobunaga's Ambition, Romance of the Three Kingdoms, Shingen the Ruler, and three Ultima games. I've heard Ultima: Exodus in particular mentioned as a relatively common yet forgettable SNROM donor.

A few of these (Khan, Nobunaga, and Three Kingdoms) are SOROM, which differ from SNROM primarily in having two WRAMs, only one of which is connected to the battery. SOROM can protect save RAM from stray writes even if you're using WRAM as work RAM: load the extra fixed bank code into WRAM 0, which isn't battery-backed, and the save data into WRAM 2, which is.
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Re: MMC1 questions

Post by tokumaru »

DRW, I can understand not using battery-backed CHR-RAM if you're trying to be period-accurate, since no matter how simple/cheap it is, this solution was never used by licensed games, but your "prejudice" against UOROM is exaggerated, considering that any UNROM board can support 256KB with the addition of just a few wires, and that a few licensed games did use that configuration.
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Re: MMC1 questions

Post by DRW »

Bregalad wrote:That's why I find it even weirder you don't insist more on passwords.
That wasn't my decision.
I don't work alone, I have a team of a graphics artist and a sound composer. And these are not some random strangers from the internet, these are my two best friends that I spend every lunch break with.

I wanted to do passwords, but my graphics designer is against it.
Why is she against it? Because we're not doing some simple little game like "Gauntlet", but a full-blown action adventure with 16 x 16 overworld screens, a good bunch of dungeons and a real plot where the story develops as you go along.
(Regarding the story, "Zelda" and "Final Fantasy" are even much simpler: You have an initial task and then you simply find a certain amount of a specific item and then you go to the final boss.
If you want to see what way of storytelling we will do, have a look at "Final Fantasy Adventure" for the Game Boy.)

And having passwords in such a JRPG-like top-down open-world plot-heavy adventure game is something she absolutely despises, especially since almost no NES adventure game does it.
O.k., "Willow", "Magic of Sheherazade", "Times of Lore" and "Robin Hood" do it.
Two of them are movie conversions (one of them quite crappy) and one is a western adventure game that originated on home computers.

But the real Japanese games from the action adventure and RPG genre: "Zelda", "Final Fantasy", "Dragon Warrior", "Destiny of an Emperor", "Faria", "Crystalis", "Star Tropics". They all use battery saves.

That's why I gave in and said: "O.k., fine, I'll change the game to MMC1."
You gotta have to make your team members happy.

By the way, if we did a side-scrolling adventure game like "Faxanadu", "Castlevania II" or "Battle of Olympus", she would have no problem with a password.
tokumaru wrote:DRW, I can understand not using battery-backed CHR-RAM if you're trying to be period-accurate, since no matter how simple/cheap it is, this solution was never used by licensed games, but your "prejudice" against UOROM is exaggerated, considering that any UNROM board can support 256KB with the addition of just a few wires, and that a few licensed games did use that configuration.
Well, this isn't an issue anymore anyway. We do MMC1 now because of the battery save. So, I don't need to think about whether UOROM would be acceptable for me until I do the next game.
My game "City Trouble":
Gameplay video: https://youtu.be/Eee0yurkIW4
Download (ROM, manual, artworks): http://www.denny-r-walter.de/city.html
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Re: MMC1 questions

Post by Bregalad »

Well, this isn't an issue anymore anyway. We do MMC1 now because of the battery save. So, I don't need to think about whether UOROM would be acceptable for me until I do the next game.
Indeed, and UNROM/UOROM plus saved SRAM is almost out of question for both of us because it wasn't done back then (even if it shouldn't be that hard to do with hardware).
That wasn't my decision.
I don't work alone, I have a team of a graphics artist and a sound composer. And these are not some random strangers from the internet, these are my two best friends that I spend every lunch break with.
Well you're lucky ! It remembers me 10 years ago... Now I'm alone and the advantage is that I do what I want, but the problem is that most of the cases I don't know what I want and I lack ideas/imagination like I had when I was younger. Also being alone makes being motivated much harder.
But the real Japanese games from the action adventure and RPG genre: "Zelda", "Final Fantasy", "Dragon Warrior", "Destiny of an Emperor", "Faria", "Crystalis", "Star Tropics". They all use battery saves.
Dragon Quest I and II actually uses passwords. Only from Dragon Quest III and the american Dragon Warrior I (released almost simultaneously) they started to use battery saves.
Why is she against it? Because we're not doing some simple little game like "Gauntlet", but a full-blown action adventure with 16 x 16 overworld screens, a good bunch of dungeons and a real plot where the story develops as you go along.
(Regarding the story, "Zelda" and "Final Fantasy" are even much simpler: You have an initial task and then you simply find a certain amount of a specific item and then you go to the final boss.
If you want to see what way of storytelling we will do, have a look at "Final Fantasy Adventure" for the Game Boy.)
Actually whether passwords is an acceptable system or not does not depend on the game genre at all, but rather the amount of data to be saved. But oh well, if your friends /colleagues really didn't want it I think I can't change their minds :p
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Re: MMC1 questions

Post by DRW »

Bregalad wrote:Dragon Quest I and II actually uses passwords.
Yeah, even in our hypothetical reality, we're still a German company and not Japanese developers, so she would still judge the situation based on western releases of the game.
Bregalad wrote:Actually whether passwords is an acceptable system or not does not depend on the game genre at all, but rather the amount of data to be saved. But oh well, if your friends /colleagues really didn't want it I think I can't change their minds :p
I guess it has mostly to do with epicness: Entering a password makes the game feel like a simple little game. But having a battery save makes it feel like one of those huge Square RPGs.
My game "City Trouble":
Gameplay video: https://youtu.be/Eee0yurkIW4
Download (ROM, manual, artworks): http://www.denny-r-walter.de/city.html
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Re: MMC1 questions

Post by rainwarrior »

DRW wrote:MMC1 with 256 KB is already acceptable because of "Final Fantasy" alone, a hugely successful game, but I assume there are more games with this mapper and this ROM size.
Bootgod's database has a search feature for answering that kind of question:

http://bootgod.dyndns.org:7777/search.p ... attery=Yes
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Re: MMC1 questions

Post by Bregalad »

DRW wrote: Yeah, even in our hypothetical reality, we're still a German company and not Japanese developers, so she would still judge the situation based on western releases of the game.
Well, JRPGs in Europe were existant until the mid 1990s, outside the Zelda franchise. I could be wrong but don't think anyone here would even know the genre existed at all. Secret of Mana was the first JRPG-like game to be released here with a great success, but it's an A-RPG. Final Fantasy Adventure was released here before that, but I think it was largely unsuccessful (the translation is awful, too).
Final Fantasy franchise was unheard off here before 1997 and the release of Final Fantasy VII for the PS1 (ok, Final Fantasy Mystic Quest was released, but I think it sold very poorly and that nobody noticed it).

Rare was the only large NES game developer based in Europe. There was however also the company that made Asterix (based in spain) and the guys that made Elite, I think they were from France ? Also there is Software Creations, I think from the UK but only did a single NES game (Solstice), but at least it's a great game.
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Re: MMC1 questions

Post by DRW »

Bregalad wrote:Well, JRPGs in Europe were existant until the mid 1990s, outside the Zelda franchise. I could be wrong but don't think anyone here would even know the genre existed at all.
As a game company that develops NES games and who got into contact with the NES in New York in 1985, we of course have good connections to the American market. (Even "City Trouble" was programmed with NTSC in mind.) So, of course, we know about "Final Fantasy" and "Dragon Warrior". However, we only have a rudimentary knowledge of Japan-only Famicom games. That's why Katrin is aware of the battery saves in the JRPG games, but not that the Japanese version of "Dragon Quest" uses passwords. :wink:
Bregalad wrote:Final Fantasy Adventure was released here before that, but I think it was largely unsuccessful (the translation is awful, too).
Whether successful or not, this game is the one that inspired us to do a story-driven game in the first place.
This time this is even true in the real world because I couldn't find an NES game with a real on-going story. Also, I even played this game in the 90s, so yeah, in reality and in our fictitious history, I knew of the game. (I even had "Final Fantasy - Mystic Quest".)
Bregalad wrote:Rare was the only large NES game developer based in Europe. There was however also the company that made Asterix (based in spain) and the guys that made Elite, I think they were from France ? Also there is Software Creations, I think from the UK but only did a single NES game (Solstice), but at least it's a great game.
And Den Kat Games, from Germany. :mrgreen: Although I didn't decide yet whether we have been a licensed or an unlicensed developer.
My game "City Trouble":
Gameplay video: https://youtu.be/Eee0yurkIW4
Download (ROM, manual, artworks): http://www.denny-r-walter.de/city.html
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