Bookmarks tagged [non-x86]
http://www.atariarchives.org/2bml/
http://chortle.ccsu.edu/AssemblyTutorial/index.html
https://archive.org/details/ataribooks-machine-language-for-beginners
Richard Mansfield [6502 CPU]
[Machine Code for Beginners Z80 and 6502 CPUs
https://usborne.com/browse-books/features/computer-and-coding-books/
Lisa Watts and Mike Wharton (PDF) (Scroll to bottom and click on book cover)
http://skilldrick.github.io/easy6502/
Nick Morgan