I uniformly found anything but the manufacturer's references to be verbose and slow. I learned Z-80 assembly from Zilog's instruction set reference, and 6502 as

I uniformly found anything but the manufacturer's references to be verbose and slow. I learned Z-80 assembly from Zilog's instruction set reference, and 6502 assembly from the Synertek reference. Ditto the 68000. I never really learned x86 assembly because I started with some awful Scelbi book. BTW, I used assembly in a real-world project about two years ago, and one of my cow-orkers was using it yesterday. It's anything but dead.