Comment by jim_lawless

Agreed. I only recently found out about a book that Barden wrote (also a Sams book) that was published in 1977 called "How to Program Microcomputers". It explains the common workings of microprocessors and then goes over the makeup and instruction sets of the Z-80, 6502, and 6800. I wish I'd had that as a primer on assembly language and programming for microprocessors.