The DDR Research Master Thread - UPDATED 2023-04-15 - Minor Addition - SOME DDR GB1 Memory Addresses

How exactly did you make the ssq file for the song?

Converted from the DWI. The DWI and SSQ specs are both known (minus some errors in the freeze spec), so it's just a matter of converting.

do you mind if I ask how is it converted?

I made a little program. It's nothing complicated, but pretty hacky (it doesn't do doubles charts, it doesn't do lights, it doesn't do background videos, and I'm not sure whether I got the padding right).

Do you have a link to this program? I am curious to see what it can do.

It is not public at this time, no.

Are you willing to share it? perhaps pm me?

I do not intend to release it at this point; it needs some maturing first, at the very least. But I'd be interested in helping out with the SSQ spec documentation—I sent some bug reports to SaxxonPike's repository, but it seems he is busy with other things.

In other news, here's something I didn't know: Beginner steps do not have a foot rating stored. It is computed on-the-fly by means of a simple formula:

- Minimum BPM 0–179: 1 foot
- Minimum BPM 180–249: 2 feet
- Minimum BPM 250–: 3 feet

There's also some tweaks if the song is marked with certain bits in the “extra stage” field, but that's the main rule. Konami engineers are the laziest. :-P I wonder if the beginner stepcharts themselves were originally autogenerated, too? (They're stored in the SSQ, at least.)

1) In EXTREME and later not minimum but maximum BPM is used for foot calculation, that's why INSERTiON foot rating is 2.
2) DS EuroMIX 2 (and maybe first EuroMIX) foot ratings aren't BPM dependent. Example is "5, 6, 7, 8", where and have the same ratings.

Hm. If so, my min and max bpm are switched in the mdb structure. What's the right order? I had min first, then max.

An interesting question is how to suppress beginner steps, if at all possible (except for challenge-only songs).

Edit: It looks like max, min indeed is the right order, so that's where my mixup is, and max BPM indeed decides the beginner foot rating. And it appears that whenever there's a light foot rating, then there's also an assumed beginner foot rating. (You can have e.g. beginner+light+challenge, but then you can only switch between light and challenge in the options menu, since there are no intermediate steps.)

Dude, that's amazing work! Too bad that's the "ugly" version of the song... there's a much polished version but it's getting really difficult to find. I asked DM Ashura if he happens to have it.

Yeah, this is the original DWI file from TournaMix 4. :-) I wasn't aware there was a newer one, but the conversion process is automated, so I guess it could just be fed in if someone finds the file.

DDR Extreme has several hard-coded limits that together limit the number of songs to 248 (entries in the MP3 table, fixed limits in the sorting code, one-byte entries in the texture slot management code, etc.); I believe I've actually made enough patches now to lift that limit (I have a test version with 263 songs in it, and it should probably be good for a couple hundred), but it's up to 247 (!) distinct instructions patched, and there are still bugs lurking that may be hard to find and track down. And it's only tested in MAME, since it's been a decade since I last stepped on an actual Extreme.

If you manage to make it work in MAME there's no reason why it shouldn't work in a real sys573

EDIT: if you want to try something really crazy, I have an SSQ for Max Forever that I converted with another program. AFAIK, conversion of doubles charts work but that particular simfile doesn't have that mode.



👀

Well, MAME has imperfect emulation of several parts. For instance, the FPGA isn't emulated at all; it completely ignores the bitstream given to it and just decrypts the MP3s in C++ code. At some point, I know that I put the FPGA bitstream file wrongly into the archive; MAME didn't care at all, but real hardware would have crashed and burned badly.

Update: After some more patching, real hardware works fine, including with VBR. Still lots of major and minor bugs, of course.

OMG keep us informed!

(the Max Forever idea is still up 👀)

There's lots of small tidbits in this machine that I had no idea about :-)

For instance: Only yesterday, I realized why it only uses 20 MB for MP3s, when the I/O card has 24 MB RAM. It turns out it uses the last 4 MB for caching background videos! (Ie., just as a dumb data store; the I/O card is not involved in playing them.) At the start of the song, it streams them from the CD-ROM to the I/O card's RAM, and then pulls them back from there as needed.

Also, there's a lot of hidden functionality in the operator menu. Depending on the game's region (set by /s573/config.dat), things like JOINT GAME PREMIUM, GAME OVER DURING SONG, LANGUAGE, and some coin mech options are shown or hidden. I know there's at least one preexisting hack that enables the GAME OVER DURING SONG option, so that you can turn it off. LANGUAGE doesn't work, though, since there's only Japanese graphics in there anyway. Also, the region will control the “This game is sold only in Japan” display. There's even a byte you can change that makes Extreme think it's a DDR Solo cabinet, with the arrows put in the middle of the screen and all menu references to P2 removed (haven't tried six-panel, though).

Finally, Konami LZ77 is really bad. I wrote a simple LZ4 decompressor to replace the unused compression_type=2 decompressor (does anyone know what format that is for?), and it packs both denser and faster. In fact, it's so much faster that I could start decompressing banners on the fly without the songwheel lagging, which saves a lot of space in the flash.

That region change would be something really interesting to try in DDR Solo 2000, to see if a working "Dancing Stage Solo" can be done.

It depends on what exactly you'd mean by Dancing Stage Solo. It only concerns a few very specific things, it doesn't do a reskin or anything.

DDR Solo 2000 has graphic assets for a "Dancing Stage Solo" (that was never released, btw).



The naming for the language respective graphics are exactly the same as the Japanese ones. That makes me think of what would happen if somehow an European region is forced in the game.

From your screenshot, it looks like there's engl/fren/germ/ital/japa/span directories, which suggests that the language option would actually do something. So if you patch the region from JA to EA in the bootloader, it might enable the LANGUAGE option and allow you to change to a DS language?