- Thread starter kuze
- Start date
Much easier to remove the binary data it's supposed to play than locate and update assembled Z80 code.
Clearpaper
Student
Could you share more information on this?
Game data is assembled, that's why it's binary data that must be edited in a hex editor. That's why there are limits to rom hacks that can be done in a hex editor. Unless something in the rom is in plain text, it's meaningless jibberish. So without disassembling the whole Z80 rom and finding the bonus sound, reassembling the code and hoping it miraculously still runs... Just deleting the sound data is much easier. It's almost like deleting a section of a wav audio file.
Pretty much what @Neo-Alec said. My original strategy was to patch the 68k code that actually triggers communication to the Z80 to play that particular sound, but I found that when I did it that way it would sometimes result in odd side effects later like the BGM would stop playing during that stage.
I don't have any experience with Z80 coding and there is some community documentation and tools for working with the V ROM data, so going that route ended up working out great with minimal time expense. I actually like the idea of playing this way with the game code itself unmodified, any high scores should be considered legitimate IMO and if you are working towards a 1CC the 'bonus' sound gets old fast.
I don't have any experience with Z80 coding and there is some community documentation and tools for working with the V ROM data, so going that route ended up working out great with minimal time expense. I actually like the idea of playing this way with the game code itself unmodified, any high scores should be considered legitimate IMO and if you are working towards a 1CC the 'bonus' sound gets old fast.
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Clearpaper
Student
Clearpaper
Student
I note that the tail end of the "BONUS!" sound is still in the modified V ROM. You can check with the Universe BIOS Jukebox, ID# 7A0. This sound clip plays a string of sounds separate from the other sounds. I'm not too sure why this distinction was made, and why it's processed as a string of sounds. They might be ADPCM vs FM sounds.
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I contemplated locating the Z80 code to reduce its volume but then decided to go the 68k route.
I've found the 4 separate subroutines that end up playing it.
SR1: Red pick-up (shot power-up), if Power gauge is maxed, subsequent picking up plays "BONUS!" instead of "POWER UP!"
SR2: Blue pick-up (bonus points), always plays "BONUS!"
SR3: Orange pick-up (Co-op mode only: attract enemies), always plays "BONUS!"
SR4: Green pick-up (Co-op mode only: 'stealth mode', homing enemies do not target you), always plays "BONUS!"
I'm looking to replace the Blue, Orange and Green pick-up sounds to other bleeps/tones, while leaving the Red pick-up to still play "BONUS! on subsequent pick up. That reduces it significantly while retaining some of it where it logically makes sense to play. No gameplay or scoring code is touched.
Candidate sounds:-
Blue: "Tong!"
Orange: ascending-like tone
Green: descending-like tone
(On a side note, the Orange and Green status can be seen on the ships, last 4-5 seconds, and can actually be passed between players. While having the Orange status, points increment with time, presumably for the added risk of attracting enemies to you. Interestingly, the internet seems quite sparse about this. I might start another thread to further details on it.)
(A longer term goal is to add an Options screen to allow switching between the original or modified tones, plus perhaps a proper Music player like with Pulstar. There are 2 unused musics, VACANT MIND (Continue) and VARIOUS (Middle Demo) that can be played. And perhaps splitting out of the "ADPCM" sounds for individual playback. The initial hurdle is whether enough space can be cleared for the additional code. Well, the initial initial hurdle is whether I have time.)
-----------------------
I contemplated locating the Z80 code to reduce its volume but then decided to go the 68k route.
I've found the 4 separate subroutines that end up playing it.
SR1: Red pick-up (shot power-up), if Power gauge is maxed, subsequent picking up plays "BONUS!" instead of "POWER UP!"
SR2: Blue pick-up (bonus points), always plays "BONUS!"
SR3: Orange pick-up (Co-op mode only: attract enemies), always plays "BONUS!"
SR4: Green pick-up (Co-op mode only: 'stealth mode', homing enemies do not target you), always plays "BONUS!"
I'm looking to replace the Blue, Orange and Green pick-up sounds to other bleeps/tones, while leaving the Red pick-up to still play "BONUS! on subsequent pick up. That reduces it significantly while retaining some of it where it logically makes sense to play. No gameplay or scoring code is touched.
Candidate sounds:-
Blue: "Tong!"
Orange: ascending-like tone
Green: descending-like tone
(On a side note, the Orange and Green status can be seen on the ships, last 4-5 seconds, and can actually be passed between players. While having the Orange status, points increment with time, presumably for the added risk of attracting enemies to you. Interestingly, the internet seems quite sparse about this. I might start another thread to further details on it.)
(A longer term goal is to add an Options screen to allow switching between the original or modified tones, plus perhaps a proper Music player like with Pulstar. There are 2 unused musics, VACANT MIND (Continue) and VARIOUS (Middle Demo) that can be played. And perhaps splitting out of the "ADPCM" sounds for individual playback. The initial hurdle is whether enough space can be cleared for the additional code. Well, the initial initial hurdle is whether I have time.)
