Why does Mega Man have sound problems with Game Genie?

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Why does Mega Man have sound problems with Game Genie?
by on (#25094)
Everytime I play Megaman 2 and 3 there are sound issues that I cannot address and gets old after about a minute or two and was just wondering how
do I fix this problem? I tried cleaning the carts but it still is happening. Any word on why this happens?

[Subject Line Fairy was here]

by on (#25100)
Yeah, I remember this. It happens with other Capcom games as well, but I never looked into it.

Galoob even had a cautionary statement:

NOTE: all codes make the music sound strange. It's harmless.

by on (#25102)
If I had access to a real game genie, and could change it's ROM, I think I could fix it with a simple sound register reset routine, used after the start button is pressed. Short of that, you'd need at least 1 code in the game genie to fix the error, possibly more than 3.

by on (#25111)
What other Capcom do this to the sound?

by on (#25130)
Here's a post about the GG and Capcom games (with special NSFs for those games :-))

http://nesdev.com/bbs/viewtopic.php?p=7186

It had to do with the music driver in Capcom's games from ~1989-1990. The version at this time didn't set the sweep registers, while the Game Genie mucked around with said registers.

by on (#25169)
ccovell wrote:
Here's a post about the GG and Capcom games (with special NSFs for those games :-))

http://nesdev.com/bbs/viewtopic.php?p=7186

It had to do with the music driver in Capcom's games from ~1989-1990. The version at this time didn't set the sweep registers, while the Game Genie mucked around with said registers.


It only talks about Megaman games!:-)