Amiga doesn't have a
SID chip, C64 does. No ADSR, no LFOs in Amiga (unless if you program them with software).
Amiga sound chip is
Paula (MOS Technology 8364). You can find full programming information from the Amiga Hardware Reference Manual (can be found from the Amiga Developer CD for example).
Anyway, poking the hw directly is rather crude thing to do, esp when a lot of people have upgraded their amigas with nice sound cards. You might want consider using
AHI.
