Thoughts about adding YMF262 to Famicom cart

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lidnariq
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Re: Thoughts about adding YMF262 to Famicom cart

Post by lidnariq »

I mean, I already pointed out the reasons that the MMC5's fancy-pants extra features are not particularly helpful.

They all
1- Are hard to use, and/or
2- Are extremely limited, and/or
3- Consume more of the extremely limited CPU-to-PPU-memory bandwidth, and/or
4- Consume more of the extremely limited sprite overdraw.

And all of those features take up fusemap space that could be better used doing something else.

As far as what mappers we've seen homebrew use?
NROM, tons of it, because it's an excellently achievable stopping point. A nice measurable amount of assets, finishable in a reasonable amount of time.
UNROM (the fixed bank is a great stepping stone)
BNROM (lots of storage for assets for a minimum of manufacture cost)
MMC3 (so you really do want fine-grained bankswitching and/or a raster IRQ. Hope it's worth the cost premium)

None of the features of MMC5 would meaningfully improve these.

There's a reason I pointed out that the only request we have repeatedly heard from developers is wishing to get around that extremely limited CPU-to-PPU-memory bandwidth. It's the unified major sticking point that you'll collide with regardless of the mapper you use.


The other mapper we've seen that uses 8x8 attributes is Quietust's port of Drip, which was at least partially designed to have a usable interface instead of having the kitchen sink.
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Ben Boldt
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Re: Thoughts about adding YMF262 to Famicom cart

Post by Ben Boldt »

I understand you are saying that a complicated/standard mapper is not going to help make NES development more approachable. I trust your experience on this -- that this idea would tend to lead us in the wrong direction, or possibly to a dead end. I accept that now.

We can believe that many naive NES/FC developers with big ideas will emerge as millennials begin to retire, driven strongly by nostalgic parts of their past. We have that asset coming our way, for totally free. I think that is a realistic thing to expect. So let me revise my question: What can we volunteer to work on now, ahead of time, to make things approachable for future developers that will emerge? How can we make it so that someone fresh and new with big ideas wandering into here can find a way without being told "no", and do it without convincing others to pay or do work for them?
tepples
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Re: Thoughts about adding YMF262 to Famicom cart

Post by tepples »

If you define "millennial" as born 1980-1999, and "retirement" as turning 65 (using US Medicare's standard), you're looking at 2045-2064.
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Ben Boldt
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Re: Thoughts about adding YMF262 to Famicom cart

Post by Ben Boldt »

I am not talking about a short-term plan here, or starting in asking for help or implementing something today. None of us will ever be developing under the pressure a schedule, and that changes the scale of things, and makes it more important to drive towards being more approachable to the newcomers in the future. We have a very good luxury of time here to start thinking and getting organized, and also time for some of us to potentially start appreciating our advancements before then.

We can take all of these plentiful crazy dreams, and filter them into a united vision, considering cheaper parts of the future, which would allow us to develop and evolve a complex, easy-to-use solution, very small bits at a time where and when people see that they can contribute. At this point, that consists of gathering ideas in an organized way instead of tossing them.
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pubby
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Re: Thoughts about adding YMF262 to Famicom cart

Post by pubby »

Once you reach MMC5 levels of mapper enhancements, it becomes a question of why are you even coding for the NES. Just make PC games. It worked for Shovel Knight.

If you insist on making the utlimate mapper though, this idea of "MMC7" seems limited. Why not shoot for the stars? Put a co-processor on the board and have it do 99% of the computing work. Put a pair of speakers on it too and use true PCM sound. That's how you push the boundaries. /s
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rainwarrior
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Re: Thoughts about adding YMF262 to Famicom cart

Post by rainwarrior »

Ben Boldt wrote:How can we make it so that someone fresh and new with big ideas wandering into here can find a way without being told "no", and do it without convincing others to pay or do work for them? ... At this point, that consists of gathering ideas in an organized way instead of tossing them.
Nobody's saying no to the idea of a new mapper, we're just saying "no it's not going to become a new standard for NESDev." The idea is fine, but your expectations for its purpose weren't realistic.
Ben Boldt wrote:We can take all of these plentiful crazy dreams, and filter them into a united vision, considering cheaper parts of the future, which would allow us to develop and evolve a complex, easy-to-use solution, very small bits at a time where and when people see that they can contribute.
Well, people are already doing that in myriad ways. I already mentioned NESMaker. Sour took up a mission to make a newer better debugging emulator called Mesen. In my own work I'm trying to make open source examples, and contribute to emulators or other tools (e.g. NSFPlay). Dougeff is writing tutorials and improving a music library called Famitone. Tepples made his own music engine called Pently, and is continually providing open source examples and tools. Many of us contribute to the NESDev Wiki, either adding new information or improving the quality and organization of existing information. The Mojon Twins released an open source NES game framework. kasumi is making an NES animation tool. NovaSquirrel wrote a powerpak implementation for a popular new(ish) mapper, and released a substantial platformer game as open source. InfiniteNESLives has been manufacturing boards and development tools for a reasonable cost. RetroUSB released a high quality NES clone. Lexington Alexander is interviewing NES developers and publishing a periodical magazine. Lots of people on this forum make themselves available for more direct and personalized answers to questions. lidnariq has been particularly helpful in the area of electrical engineering questions. (I want to keep making this list, but there's just too much to possibly be comprehensive. Apologies to everyone missed out here.)

There's a ton of ongoing work to this effect, these are just a few recent examples off the top of my head. There's a lot of stuff I've omitted, and this place goes back well over a decade. At one point this place was just a pile of links to miscellaneous text documents and relatively small demos. The kind of progress you're talking about is happening constantly.
Ben Boldt wrote:I am just sharing my ideas and looking for feedback how we could work together as a group to create large-scale, well-planned platforms to support each other, and also to provide my skills wherever possible. ... What can we volunteer to work on now, ahead of time, to make things approachable for future developers that will emerge?
So... that's an extremely vague and open ended question. All I can say is maybe take a look around and try to find an existing project that you think you could improve. My very incomplete list above is a small but varied set of examples of things that seem to fit the bill, depending on what your interests are. You could try making a game or a demo and see where you feel the experience could be improved, then address that.
plgDavid
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Re: Thoughts about adding YMF262 to Famicom cart

Post by plgDavid »

Ben Boldt wrote: From your experience, what do you think is the most fitting synth for a future MMC7 NES game? For an actual synth chip, YMF262 is very easy and cheap to attain, and there is something special about using the real chip -- not to discount the accuracy of the emulation demonstrated in the video.
There indeed is something special with a real chip, even if one could model it 100% (or close to) using FPGAs or real fast ARM code (which I sometimes do). Funny but knowing its there gives me some goosebumps. Hearing the subtle background noise or characteristic dirt only the real thing can provide as well.

I wish to offer both options (I have a ARM chip co-processor Famicom cart as well - that does audio).
EDIT: https://twitter.com/plgDavid/status/1041696587125207040
But yeah I agree with the others. pushing this design officially is not what I have in mind. I'm really doing a crazy small scale personal project, and if I get a hundred chipmusicians using it would please me greatly.

However! And I talked about this with others as well. There is a critical need for high quality Famicom cartridge shells.
The entry point for injection molding is not for the faint of heart. Anyone interested in making homebrew games targetting Famicom (using any mapper or mapper clone)? As long as we define a common pcb footprint. Thinking standard ofiicial 'Famicase' style carts, but without the rectangular hole in the middle.
lidnariq
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Re: Thoughts about adding YMF262 to Famicom cart

Post by lidnariq »

plgDavid wrote:(I have a ARM chip co-processor Famicom cart as well - that does audio).
One idea I've been playing around with for a while is a hardware synth that automatically encodes its output as DPCM and lets the NES stream it.

No idea if your ARM+GAL design gives you enough rope to try that, or if you're interested. But it feels like an interesting way to get no-modification expansion audio on NESes. Obviously it's redundant on a Famicom.
plgDavid
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Re: Thoughts about adding YMF262 to Famicom cart

Post by plgDavid »

lidnariq wrote:
plgDavid wrote:(I have a ARM chip co-processor Famicom cart as well - that does audio).
One idea I've been playing around with for a while is a hardware synth that automatically encodes its output as DPCM and lets the NES stream it.

No idea if your ARM+GAL design gives you enough rope to try that, or if you're interested. But it feels like an interesting way to get no-modification expansion audio on NESes. Obviously it's redundant on a Famicom.
That is surely a very interesting idea, but even at 'F' speed DPCM's audio quality is erm for me. Don't get me wrong I love the sound of it. BUT Think we both messed with DPCM 'as a synth' iirc?
https://twitter.com/plgDavid/status/926476518733287424
That, in my synth nerd opinion, is the way to go for that. (surely limits the tonal variations of a real synth though)

My arm co-processor handshaking is really minimal, its really just a slave, usually mapped at $5000
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