What are ROM Nametables useful for?

Discuss technical or other issues relating to programming the Nintendo Entertainment System, Famicom, or compatible systems. See the NESdev wiki for more information.

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puppydrum64
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Re: What are ROM Nametables useful for?

Post by puppydrum64 »

Well to each their own. I just thought that was impossible on the NES so to see it in a NES game was cool in and of itself.
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aquasnake
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Re: What are ROM Nametables useful for?

Post by aquasnake »

There are several mappers providing (or reserving) this mapping method:

mapper 17,26,90 -- reserved, probably no game even used

mapper 68 -- actually used
lidnariq
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Re: What are ROM Nametables useful for?

Post by lidnariq »

(Mapper 19, not mapper 17...)
NewRisingSun
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Re: What are ROM Nametables useful for?

Post by NewRisingSun »

Mapper 17 uses it on a game converted from mapper 68. :lol:
Mapper 90 uses it in the games Mighty Morphin' Power Rangers III and and Shin Samurai Spirits 2.
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Ben Boldt
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Re: What are ROM Nametables useful for?

Post by Ben Boldt »

The wiki lists quite a few more via Category:Mappers_with_ROM_nametables

https://wiki.nesdev.org/w/index.php?tit ... nametables

INES Mapper 019
INES Mapper 035
INES Mapper 068
INES Mapper 209
INES Mapper 211
NES 2.0 Mapper 281
NES 2.0 Mapper 282
NES 2.0 Mapper 295
NES 2.0 Mapper 358
NES 2.0 Mapper 386
NES 2.0 Mapper 387
NES 2.0 Mapper 388
NES 2.0 Mapper 397
Namco 163
VRC6

It is a little confusing because most are just PCB variations with the same "J.Y. Company ASIC".

VRC6 (mapper 24, 26)

Namco 163:
INES Mapper 019

INES Mapper 068

J.Y. Company ASIC:
INES Mapper 209
INES Mapper 211
INES Mapper 035
NES 2.0 Mapper 281
NES 2.0 Mapper 282
NES 2.0 Mapper 295
NES 2.0 Mapper 358
NES 2.0 Mapper 386
NES 2.0 Mapper 387
NES 2.0 Mapper 388
NES 2.0 Mapper 397

Really only 4 then.



Edit:

Thanks for adding 017 to the category NewRisingSun. I did a little cleanup as well with these J.Y. mappers and added a new category for them.

I am really surprised that MMC5 does not support ROM nametables. Maybe it DOES and we just don't know it.
lidnariq
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Re: What are ROM Nametables useful for?

Post by lidnariq »

Ugh pirate mappers that pretend you can bake a RAM dump from a copier into a NES file.
NewRisingSun
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Re: What are ROM Nametables useful for?

Post by NewRisingSun »

They're not RAM dumps and not from "copiers". :roll: Let's not perpetuate myths from 1996.
Ben Boldt wrote:I am really surprised that MMC5 does not support ROM nametables. Maybe it DOES and we just don't know it.
If it does, registers $512C to $512F would be the most likely candidates to select the bank of each of the four nametables. Of course, some other bit would first have to enable their function. I wonder if the guy who decapped the MMC3C could be interested in decapping the MMC5.

Also, I wonder if the J.Y. ASIC should have its own mapper-independent page. The current structure makes it that mapper 90 is in the ROM Nametables category when it explicitly does not support them.

(And screw you, J.Y., for first designing an all-purpose ASIC but then wiring it up differently for every other multicart.)

Finally, there might be the need for a wiki page listing games that use ROM nametables, so that emulator or FPGA authors have something to test:
  • After Burner
  • After Burner II
  • Final Lap
  • Mappy Kids
  • Mighty Morphin' Power Rangers III
  • Mighty Morphin' Power Rangers IV
  • Shin Samurai Spirits 2
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Ben Boldt
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Re: What are ROM Nametables useful for?

Post by Ben Boldt »

Do you know if there is a pinout for this chip anywhere? I don't even have a clue what it looks like or how many pins. I wonder if it is a small SMT or a giant DIP-40, or only ever exist as a glob, etc.

Also, what is your main source of info for pirate cart hardware info? I always go to NesCartDB when I want to know exactly what is in a specific cart but it seems they have intentionally excluded all pirate carts there (understandably).
NewRisingSun
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Re: What are ROM Nametables useful for?

Post by NewRisingSun »

I don't know that nescartdb specifically excludes bootleg cartridges; I believe it's just that the owners of bootleg cartridges don't bother sending stuff to nescartdb. Especially since most bootleg cartridges use globtops, which makes it difficult to supply all the information that nescartdb wants.
Ben Boldt wrote:Do you know if there is a pinout for this chip anywhere? I don't even have a clue what it looks like or how many pins. I wonder if it is a small SMT or a giant DIP-40, or only ever exist as a glob, etc.
The J.Y. Company ASIC? It has only been seen as a glob. krzysiobal has described the pinout here for a mapper 90 cart.
Ben Boldt wrote:Also, what is your main source of info for pirate cart hardware info?
PCB images from collectors, debugging the code, analyses from people like krzysiobal, hardware tests with a dumping device.
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Ben Boldt
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Re: What are ROM Nametables useful for?

Post by Ben Boldt »

So a pinout isn't probably very useful since this is a glob... But still interesting. I think the schematics in your post are only from krzysiobal's ROM fix board. The rev 1 schematic has his CPLD that he ended up not needing in the rev 2 of the board, but that's not the JY ASIC. The PCB photos are there making it at least possible to figure the pinout though.


Edit:

Oh he does have it!
Image
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