Castlevania III MMC3 hack

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pfox
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Re: Castlevania III MMC3 hack

Post by pfox »

Any progress with this? Can you share the current version? I'd like to test it out.
pfox
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Re: Castlevania III MMC3 hack

Post by pfox »

:( damn
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Banshaku
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Re: Castlevania III MMC3 hack

Post by Banshaku »

Maybe the author is just busy and cannot answer at the moment. If you see the post, it was some in 2012, 2017~18 so I guess he/she's not a regular here ;) I'm sure the author will post back once available.
pfox
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Re: Castlevania III MMC3 hack

Post by pfox »

Banshaku wrote:Maybe the author is just busy and cannot answer at the moment. If you see the post, it was some in 2012, 2017~18 so I guess he/she's not a regular here ;) I'm sure the author will post back once available.
Yeah you're probably right. It's just that this thing is huge for a Famiclone community that's why I'm into it. I collect clone systems.
johannesmutlu
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Re: Castlevania III MMC3 hack

Post by johannesmutlu »

Am personally really curious how the author of this castlevania 3 mmc3 hack managed to make it work since the mmc5 chip also supports 16K banks while the mmc3 chip only supports 8K banks and so i believe that castlevania 3 makes use of those 16K banks for chr data (maybe for animated tile sets) or it makes use of 16K banks for it’s prg data(,let’s say that IF the game makes use of 16K prg data for each level,that means that each level needs to be splitted and/or moddified to fit into sections of 8K and load one after the other section of it to round it up to 16k,
But if the game only makes use of 16k banks of chr data for it’s animated tile sets,that meand we have to disable animated tile sets from each level to make it all fit into 8K
The worst scenario might be to compremize both 16K prg & chr into 8K data to heavily downgrade the game,not mention the dpcm channel that has to play along with it,
Sure we might only need to disable dpcm playback but that would be really sad,
If the fully fixed mmc3 version of castlevania 3 could just run fine with dpcm playback with less or no animated tile sets at all,i would accept that,
But if many background tile tile sets has to be removed entirelly along with the absents of dpcm playback,that will be not acceptible for me,
But hey who ever knows what will be squeezed out of the mmc3 chip to make it faithfull to it’s mmc5 chip version counterpart as much as possible and am also very curious about that 3 in 1 castlevania rom hack game😁👍
OmDRetro
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Re: Castlevania III MMC3 hack

Post by OmDRetro »

Seems like there have been multiple attempts by different users. A couple variations done by a user named "Online"(not from this forum) and some other whom I can't identify, but it could be this person. I attached the patch files here for those who'd like to try it. :D

Bugs I found on the MMC3 conversion (non-debug menu variant):
  • Vertical scrolling graphical glitches
  • Password Menu Icon graphical glitches
Attachments
CV3(U)-MMC3-Conversion Pack.zip
Contains multiple versions for MMC3 Conversion
(231.18 KiB) Downloaded 89 times
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aquasnake
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Re: Castlevania III MMC3 hack

Post by aquasnake »

still glitchy

mmc3 can not achieve 1 screen morroring, nothing improved since "THE LAST HACKING"(not comparing to the original version)
cv3_mmc3.png
cv3_mmc3.png (13.02 KiB) Viewed 5275 times
Last edited by aquasnake on Mon Nov 13, 2023 8:14 pm, edited 1 time in total.
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Fisher
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Re: Castlevania III MMC3 hack

Post by Fisher »

aquasnake wrote: Mon Jun 05, 2023 8:37 am still glitchy

mmc3 can not achieve 1 screen morroring, nothing improved
cv3_mmc3.png
Isn't that what TLSROM do?
It even has a different mapper assignment (118?) because of that.
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aquasnake
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Re: Castlevania III MMC3 hack

Post by aquasnake »

Fisher wrote: Wed Jun 07, 2023 2:46 am
aquasnake wrote: Mon Jun 05, 2023 8:37 am still glitchy

mmc3 can not achieve 1 screen morroring, nothing improved
cv3_mmc3.png
Isn't that what TLSROM do?
It even has a different mapper assignment (118?) because of that.
this game has H/V, 1-a/1-b and 1-c mirroring modes, so controlling these modes shall take at least 3 bits, while mmc5 uses 8 bits to switch 4 name table spaces from 3 phisical banks
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krzysiobal
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Re: Castlevania III MMC3 hack

Post by krzysiobal »

aquasnake wrote: Mon Jun 05, 2023 8:37 am still glitchy, mmc3 can not achieve 1 screen morroring, nothing improved
I don't understand your demanding attitude. Somebody spent a lot of work in that, doing all his best to convert all the MMC5 register writes into MMC3 registers, converting IRQ counter and the most important - CHR bank structure from 4x1kB to 2x2kB + 1x1kB and you say nothing improved?

Indeed this game requires ability for H/V/1sc mirroring (just like the Japanese version does), but this is just the only thing that MMC3 cannot provide. If you looked at the $A000 writes by the game, you probably should notice that this hack writes not only $00/$01 to this register, but also $02 and $03 and sometimes $ff. This should suggest you that if you treat the mirroring bits just like MMC1 does
(00=1scA, 01=1scB, 10=V, 11=H), the problem that you showed on your screenshoot disappears.

Indeed, MMC5 version requires also third nametable, while the Japanese version does not.
Third nametable is used (only?) in the MMC5's 6-03 level ending when water starts to fill the screen (and the 6-04 level which is continuation of that)
cv3 mmc5.png
So how did they do it in VRC6 version? Simply by using first nametable for level (horizontal mirroring) and second nametable for water.
cv3 vrc6.png
Because this level uses horizontal scrolling, there are glitches on the left edge of screen and vrc6 version tries to hide that by not displaying leftmost 8 pixels. You can notice that because there is no "S" in "SCORE", no "P" in "PLAYER" and no "E" in "ENEMY"
cv3 vrc6 #2.png

And what about the MMC3 version? It works like MMC5 version (no glitches because of vertical mirroring), but lack of 3rd nametable results in no water displayed (just black screen in that area). Good enough.
cv3 mmc3.jpg
I havent checked why the boxes in password screen are not displayed correctly.
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