2A03 envelope generators

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2A03 envelope generators
by on (#65459)
Am I correct in my understanding that the initial envelope when the generator starts/restarts in always $F? There's no way for the programmer to set an initial envelope value like on the Gameboy?

by on (#65460)
Correct.

by on (#65473)
That's one of the reasons why most NES music engines switched to software envelopes starting in the NROM-256 era.

by on (#65490)
Unlike the Game Boy, you can easily set a channel's volume directly, so you don't need to deal with any LFO parts of the APU. Follow the model in the APU basics article and you don't need to know anything else about the APU (except DMC, which I need to add).

by on (#65496)
This is not for a playback library. I'm emulating the APU part of the 2A03.