1. biolizardshadow

    OP biolizardshadow GBAtemp Regular
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    Is their anyway to find where the direct sound voice limit byte is within GBA roms? The track limit was easy to find since it's at the top of the voicetable and I was able repoint it to get 16 tracks; all I need now is to change the number of direct sounds that the game can play then I'm all set the only problem being that I'm not sure where that byte is, I looked at a Pokemon rom hacking tutorial and the video pointed to bytes 00 C5 94 00 where C5 represents that only 5 direct sounds can be played at once and was located at address 001DD0C0. The only problem with this is that I'm not hacking a Pokemon game, so Is there a way to find this byte among all of the other bytes In the game. The game I'm currently working on has a direct sound voice limit of 6 so the byte should be something like this C6? Just wanted to know if their are any commonalities when it comes to the direct sound voice limit byte in GBA games. Any help would be appreciated.
     
  2. FAST6191

    FAST6191 Techromancer
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    You may be heading somewhat into uncharted territory there.

    If for some reason I wanted to do this I would probably assume I am going to have to characterise the sound format in general (or at least aspects I want of it) and then work on increasing limits/adding extras.
    You might have a shorter way in by starting at the end (that being a sound being played) and working backwards to find the library as it were and then figuring out what it would take.
     
  3. biolizardshadow

    OP biolizardshadow GBAtemp Regular
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    What do you mean by that exactly? Isn't it just finding the byte that controls direct sound voice limit and then just changing it so you can get more sounds to play?
     
    Last edited by biolizardshadow, Aug 26, 2020
  4. FAST6191

    FAST6191 Techromancer
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    Many things are but a single byte or two when all is said and done. The trick however is getting to that point, and even for those games with a shared sound engine (quite a few, not as many as others - https://www.romhacking.net/documents/462/ ) I don't know if we have an easy look for this known value and go from there.
    That then leaves you hacking a game, which you can either do head on and figure out how it all works (long time to do, will however understand the audio system for the game) or backwards (a sound will be played, possibly in response to a button press so can watch buttons* and go from there, and by working your way backwards you will end up with the sound sample handling somewhere in there and then can figure out what is needed to expand it)

    *the GBA buttons are in a known location. Some games will copy their state every frame and go from there, others will read directly. Anything that happens as a result that tickles the sound registers presumably being where you want to look.
     
  5. biolizardshadow

    OP biolizardshadow GBAtemp Regular
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    Does that mean their might be clues within the sequence or sample data and if so where might they be located? I'm a major noob when it comes to this stuff.
     
    Last edited by biolizardshadow, Aug 27, 2020
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