You are a very skilled technical writer. One way to discern this is asking at a given point, "What question just likely popped into their mind after what they have read?" (you don't have to be right, just close) ... and importantly, "Do they need a little break from the main outline?" Your brief tangents in light blue are a perfect answer to both questions. Your terminal examples show what things really look like, or how they appear to people who work with the code every day. Your narrative glue shows impeccable grammar and flow. Don't try to change your style one bit, let it change itself over time.

Never went to college or high school. When I was 17 in 1981 and had been already been deep diving into several different types of computer systems over 3 years, I would have died to read what you have written, just the way it is written. It would have answered so many questions directly, fortunately I sometimes had other peoples' code to look at (and Vector Graphic actually included commented Z80 assembler for their entire BIOS in the manual, many pages!) but when you are short on examples to look at, that's when the real disillusionment sets in. I love today's world, one is only a few keywords away from great examples. The challenge is to present them in a way that someone reading puts it all together and becomes excited about understanding.

Great work!