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Updated GEMS2MID? (Problems with current one)

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Updated GEMS2MID? (Problems with current one)

Post by birdmanager6 »

So I have been extracting data from virtually every MegaDrive ROM I can find, but the tool fails to convert from a number of different files. The error that GEMS2MID outputs is usually something along the line of "Jumping to invalid index xxxxx!" before the program crashes with "gems2mid.exe has stopped working". This happens either right before it gets to track 1 or after a certain amount of tracks. The DAC function works properly, however, and these strangely mostly play perfectly with no crashes with GEMSPlay. I am so furious that I can't get MIDIs from some of these. :x
Here are some of the ROMs that I have extracted data from that are problematic with GEMS2MID:
- Andre Agassi Tennis (JE) (REV 01) [c][!]
- Andre Agassi Tennis (JU) (REV 00) [!]
- Pirates! Gold (Beta)
- Pirates! Gold (U) [!]
- Simpsons, The - Bart's Nightmare (W) [!]
- Smurfs, The (E) [!]
- Spirou (E) [!]
- Star Trek - The Next Generation (U) (REV 00) [!]
- Star Trek - The Next Generation (U) (REV 01) [!]
- Sylvester & Tweety in Cagey Capers (Beta)
- Sylvester & Tweety in Cagey Capers (W) [!]
- WWF Royal Rumble (W) [!]
- WWF Wrestlemania Arcade (W) (Aug 1995) [!]
- WWF Wrestlemania Arcade (W) (Sep 1995)

Can this program be updated to fix at least some of these games (and more, if there are any)? I appreciate your help.
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Post by ValleyBell »

Maybe those game use GEMS 2.8? In that case the format of internal file pointers is slightly different.

Some time ago I updated gems2mid to support that version of the format as well, but I apparently never posted it anywhere. (I probably just posted the link in IRC - that unfortunately happens a lot.)
Try this version, maybe it works. (You might need to use additional parameters if the format autodetection goes wrong.)

Post by birdmanager6 »

Doesn't work. In fact, that's the version I was using. I tried setting the pointer format option to 2.8 but it doesn't work. I'm confused as to why these ROMs fail...
Have you tried converting any of the ROMs I listed? Then maybe you could replicate what I'm facing...
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Post by ValleyBell »

I haven't converted those games, no. I might have a try tomorrow or sometime during the weekend.
I also don't have rips of some of those games you listed. So far I can find Simpsons, Smurfs and Sylvester & Tweety in my archives. Those might be my test cases for now.
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Post by ValleyBell »

As it turned out, the Smurfs game uses the "goto" sequence command to make the songs loop.
I never encountered this command in the games I tested, which is why didn't notice that it doesn't work at all in gems2mid. (It also doesn't work properly in GEMSPlay due to a typo.)

There are 2 things that gems2mid does wrong:
1. The offset (that is part of the jump) is treated as absolute file offset while it should be relative. (This causes the message.)
2. It doesn't detect jumping to previous parts of the song, so even if it would work, it would then end up in an endless loop.

Here is a fixed version that fixes both issues. If you're interested in the actual fix, you can look here.
Now it also doesn't crash in case of invalid offsets. Instead it just stops converting the current track.

Post by birdmanager6 »

Sorry to bother you, but that GEMS2MID EXE seems to be for GEMSSCAN, not GEMS2MID. You must have accidently compiled the wrong file. The C file is correct, though, but I don't know how to compile it.

Admin edit: Removed fullquote.
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Post by ValleyBell »

Ah, oops. Sorry, I indeed accidentally picked the wrong file. (I have a sort of special process for compiling these small tools.)

I fixed the archive, please download again.

Re: Updated GEMS2MID? (Problems with current one)

Post by MixerProductions »

Is there a version of this that can extract the sequences for Aero the Acrobat 1 and 2?

I could have sworn I used a version of this to rip those sequences in the past, but my hard drive got corrupted and I lost them :shock:
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Re: Updated GEMS2MID? (Problems with current one)

Post by ValleyBell »

I'm pretty sure that I didn't update gemsscan since the first release.
Maybe you got rips from someone who ripped the data manually from the ROM? I don't seem to have Aero the Acrobat in my archives.
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