Textbook was decently confusing about defining registers and operands, so this was helpful:
https://docs.oracle.com/cd/E19120-01/open.solaris/817-5477/ennby/index.html
I felt like I had a pretty good understanding of what was going on, but I don't have any idea what the low-order/high-order bytes do or where they are (page 184 has an example in the aside).
If we could walk through the examples in 189, I think that would help me piece things together
Jim says :
I've added a bunch of links to resources for systems stuff at your tutorial page ... but will also need to remind myself of what's what.