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Last updated on Oct-18-2019 Download

Minimum amount of storage space a flash cart should have.

Minimum amount of storage space a flash cart should have.
by on (#92155)
How much and why? I myself think 2MB, as many many projects that are easy enough to bring to NES would needs the graphics space. Pokemon is one good example, lots of images and data there. What do you think?

Extra:Minimum supported WRAM? Mine is 32KB. 128KB would be very nice, though.

by on (#92156)
2MB would be cool to have, but I don't think it's the minimum. With 512/512 it should be possible to do everything we consider "typical NES". 2MB would be more for new ideas and experiments, which I'm all for.

by on (#92158)
512K/512K. That's enough for any licensed game. Having any more is purely for hypothetical reasons and generally shitty unlicensed games.

by on (#92160)
MottZilla wrote:
That's enough for any licensed game.

I would really like if we could all think outside of the realm of licensed games, and consider what we could achieve if we had some more memory. Smooth animations, animated patterns, fake parallax, huge worlds... these would benefit greatly from some extra memory, but a decent mapper to manage that memory would be crucial.

by on (#92161)
Is the primary goal to play every rom you can find on the net or to for homebrew development? In my opinion there is a lot more room for improvement besides merely allowing for more memory. It's easy (but expensive) to slap on more/larger SRAM. You could save money by going with flash but then have the downside of programability and write cycle limit. If memory is such an issue the best solution I see is to add an SD card on the cheap. There isn't much value in having 2MB of addressable memory on a devcart IMO.

I think just having a few KB of dual ported memory would be a lot more powerful than having an unlimited amount of memory. Having a more powerful mapper would be a better advantage than more memory as I see it.

by on (#92165)
infiniteneslives wrote:
If memory is such an issue the best solution I see is to add an SD card on the cheap. There isn't much value in having 2MB of addressable memory on a devcart IMO.

Unless you're trying to prototype a multicart that's that big.

by on (#92172)
It's trivial to add two address lines to make a 4M/4M devcart 8M/8M. 27C040 and 27C080 also still come in the same package so that's the logical cutoff point. For WRAM it's 256Kbits since it's the last DIP28, and 1M will give you as much RAM as a SNES game. Unless you're "backporting" a SNES game you can probably work without it.

by on (#92173)
tepples wrote:
infiniteneslives wrote:
If memory is such an issue the best solution I see is to add an SD card on the cheap. There isn't much value in having 2MB of addressable memory on a devcart IMO.

Unless you're trying to prototype a multicart that's that big.

Why? Just select which game you want and load it into memory. In that aspect the power pak is effectively one big customizable multicart.

by on (#92175)
infiniteneslives wrote:
Why? Just select which game you want and load it into memory. In that aspect the power pak is effectively one big customizable multicart.

I understand that. But why were Short Order and Eggsplode sold on one cart? Why were three games based on the Hebrew Scriptures sold on one cart? Likewise with its sequel? Why was Dr. Mario sold along with Tetris on Super NES and along with the game formerly known as Tetris Attack on GBA? And for cricket's sake, why did Nintendo pull out all the stops and put 200+ games on one Game Pak?

What I'm trying to do is put together a single cartridge that collects the NES homebrew community's best efforts to demonstrate once and for all that even unpaid volunteers can outcode Active Enterprises. I can get up to about 20 games in one 512 KiB collection on the PowerPak, but I have a numerological reason why I'm aiming for 53. Think of it as like Memblers' Garage Cart on Cheetahmen-sized steroids.

by on (#92176)
kyuusaku wrote:
It's trivial to add two address lines to make a 4M/4M devcart 8M/8M. 27C040 and 27C080 also still come in the same package so that's the logical cutoff point. For WRAM it's 256Kbits since it's the last DIP28, and 1M will give you as much RAM as a SNES game. Unless you're "backporting" a SNES game you can probably work without it.


SNES is the reason I don't see why you need a NES cartridge with so much memory. If you really need that much memory, maybe what you really need is to make your project on SNES or Sega Genesis instead. Or something even newer.

by on (#92180)
Yeah, but then if you move to snes if the data is images and maps and such, that'll grow to be even bigger, instead of needing 1MB, you'd need 4MB for the more graphics, tile layers, program space, etc.

by on (#92182)
Good news, 4 megabytes eprom and flash memories are cheap. No problem. You could actually get even more with SNES. 8 or even 12 megabytes are possible without an active memory mapper.

by on (#92183)
Yeah, but then you also have to fill that with higher quality, more quantity, content.

by on (#92196)
Well, if you can make a new game and actually use up like 2 megabytes of CHR-ROM, I'd like to see it. Not sarcasm or anything. It would be alot of animation I imagine and I suppose you could do alot with that. Like you suggested parallax backgrounds just by huge amounts of CHR could be possible, and animation of objects could be very fluid. Neo-Geo games are an example of what you can do with just massive amounts of video memory.

by on (#92199)
2MB, because those games do exist.

by on (#92245)
Why does there need to be a minimum? You should choose a solution that's suitable to the application you want to use.

by on (#92257)
Perhaps someone only wants to manufacture one model to start with and then branch out into multiple sizes later. It would leave a bad impression on early adopters if the first model were not suited for its purpose due to being too small.

by on (#92267)
Personally, I wouldn't bother with more storage space than can be easily purchased for "mass" producing carts. The largest still-being-manufactured 5V ROM is 1MB.

(Numonyx does make 3.3V 128MB non-BGA ROMs, but they are not 5V tolerant)

by on (#92274)
One of the main issues that plays into this question is also how convenient you'd like it to be to program. EEPROMs are a PITA, flash can be okay but it limited in write and read cycles and slower to program. SRAM is the preferable option for a development cart since it's easy/quick to program and unlimited write/read cycle life.

SRAM larger than 512KB gets expensive quick, and 512KB srams aren't cheap themselves but still not too bad under $10 each.

My solution for the NESDEV1 was to try and divide it up a bit. I've got 512KB of CHR RAM, and 32KB of WRAM, and dual ported SRAM in the CPLD. For PRG memory I only have 512KB of SRAM but I also have 512KB of Flash that socketed in PLCC form making it easier to replace or swap out with little risk of breaking pins.

But like someone already pointed out adding extra address lines for larger memory is not difficult to do when laying out the PCB. If people were interested in the NESDEV1 but demanded more memory space it could be done.

by on (#92276)
I will note that making using DRAM in something as slow as the NES is rather easy, by using hidden refresh. Except that (via digikey) the only 5V DRAM is 4Mx4 and $9.8 per. (But Lapis is at least committed to continuing to make them...)