The book (and course, IIRC) is split across two books. The first one focuses on the lower level systems, and I believe the seconds one deals with the bootloader

The book (and course, IIRC) is split across two books. The first one focuses on the lower level systems, and I believe the seconds one deals with the bootloader, language implementation, screen animation, and building the game. It doesn't look like there are multiple versions of the books, unless I'm missing something. I did the two versions of the course without the book, and really enjoyed both. Although the writers of https://teachyourselfcs.com/ https://teachyourselfcs.com/ only recommend the first one, so it depends what you want to get out of it and whether the approach resonates.