This page offers some documentation related to XeNTaX projects. 

 

Programming the FM-YAM 

 

FM-YAM Background (2018, video) The presentation that was given at X2018 in November 2018, recorded in the home studio a week later.
FM-YAM Quick Manual v1.0 One page manual that is also added to FM-YAM batches 1 and 2 packaging
YM3812 Datasheet Technical details of the YM3812 (OPL2) chip, on registers and capabilities
YM3526 Datasheet Technical details of the YM3526 (OPL1) chip, on registers and capabilities
Secret Weapons of Commodore information on SFX series A must-read about some of the details of the SFX Series, including the Sound Expander. A great site by Cameron Kaiser.
Programming the Adlib/Soundblaster Jeffey S. Lee's documentation on how to program the YM3812 on the Adlib/Soundblaster. This is basically the same as doing it for FM-YAM, so a great document. 

 

 

Vintage books on SID programming 

 

The Commodore 64 Music Book. Vogel and Crimshaw. 1984 Book about sound fundamentals, waveforms, SID registers, frequency (and pitch), and offers various basic programs. 
Will you still love me when I'm 64. Peter Gerrard. 1985 A book about music, SID 6581, registers and various machine code programs.