Mega Man 6: MM6 - Charge Shot Sound Fade Out

This hack alters Mega Man's charge shot charging sound so that upon holding the charge,
the sound fades out after a short while instead of looping forever.

This hack is for Mega Man 6 and/or Rockman 6 on NES/Famicom.

Mega Man 6 / Rockman 6
Charge Sound Fade Out
v1.0, 14th of April 2020


1) General Info
2) Patching
3) Compatibility with other hacks
4) Technical information
5) Credits



1) General Info

This hack is for Mega Man 6 and/or Rockman 6 on NES/Famicom.

It alters Mega Man's charge shot charging sound so that upon holding the charge,
the sound fades out after a short while instead of looping forever.

See also my Charge Sound Fade Out hack for MM4 and MM5.


2) Patching

Despite some offsets being different between MM6 and RM6, we're in luck!
This hack is compatible with both MM6 and RM6. It should be compatible with ANY MM6/RM6 rom.

Roms tested with include:

Mega Man 6 (USA).nes
MEGAMAN6.nes
Rockman 6 - Shijou Saidai no Tatakai!! (J).nes
Rockman 6 - Shijou Saidai no Tatakai!! (Japan).nes

Using an IPS patcher such as Lunar IPS.


3) Compatibility with other hacks

This hack only alters one sound definition and makes use of some free space at the end of the sound bank,
so it should be compatible with any MM6 romhack that doesn't alter that same sound or use the free space
I used for the new sound definition.

For instance this hack is compatible with Pursabe's excellent lag reduction and bugfixes/improvement hack.
This way you can enjoy his hack's lag free experience and improvements (such as fixed sliding) with this hack's
fading out charge shot sound as well.

Order of patching shouldn't matter, since my hack shouldn't modify any byte that his hacks modify,
but I tested by first patching a "Rockman 6 - Shijou Saidai no Tatakai!! (Japan).nes" rom with his patch, then mine.

You can find Puresabe's hacks here:
http://borokobo.web.fc2.com/
The ones I mentionned are called "Execution speed optimization and function expansion patch" for Rockman6 when you use
Google Translate.
While my hack is compatible with both MM6 (USA) and RM6 (JAP), his hacks are only compatible with RM6.


If you're making a hack and want to include this charge sound fade out, see the next section.



4) Technical information

Modified bytes:
Charge shot sound pointer at rom address 68AA5-68AA6
Free space at the end of the sound bank used to create the altered charging sound at rom address 6DF30->6DF95

Unlike for MM4, I did not increase the priority of the sound. It didn't seem to make sense here.
So, just like in the OG game, plenty of other sounds can cancel the charge shot charging sound.



5) Credits

ASM editing and sound editing: MetHy aka Ness

Thanks to Matrixz and MartsINY for their documentations on the sound engine.
Thanks to the FCEU X devs for their Hex Editor and Debugger.
Thanks to Rock5easily for his RM6 documentation.

Feel free to use this hack in your own hacks, no need to ask me, just a small credit is enough.

Database match: Rockman 6 - Shijou Saidai no Tatakai!! (Japan)
Database: No-Intro: Nintendo Entertainment System (v. 20180803-121122)
File SHA-1: 316BEA6B2AEF7E5ECDE995EAB4AD99DB78F85C34
File CRC32: AB1D7979
ROM SHA-1: 47336976A531FAB2592AF636A630A290EB036D18
ROM CRC32: 2D664D99