★ LITTÉRATURE ★ ENGLISH ★ Z-80 REFERENCE GUIDE ★ |
| Z-80 Reference Guide | Littérature English |
Learning and then understanding machine language is not so very different from learning any other language — English,for instance. The only difference being that English is far more tricky — but you learnt that OK. so why all the fuss about learning another one? When you set out to learn a language the first two things you'll need are a tutorial and a dictionary. This book is quite simply a Z80 dictionary. Inside you'll find a detailed description of each instruction just as a dictionary defines words. There are tabulated lists of them all with their timings and the effect they have on each flag. A whole page and sometimes more is dedicated to each so they can be covered in full, including a table of their object codes in both Dec and Hex. More than this, though, the same instructions occur in other parts of the book in different formats according to the different but relevant types of information that surround them. Perhaps a closer analogy is of a dictionary combined with a thesaurus as well. Moving through the book, you'll first come across a chapter on the three types of Z80 registers — general, specific purpose and the flag register. Most room is devoted to the flag register for the simple reason that it's the most important of them. There's also a useful table showing which instruction affects which flag. Now. very few books highlight the importance of timing in machine language and how crucial this is to games programming. Well, this one does! So. if you've no idea what a T or an M cycle is, or more to the point, if you've forgotten, then you can look it up here. But be warned, this book is not bedtime reading — unless you're in the habit of taking your dictionary to bed with you. As its title tells you. it's a reference work and as such it won't even teach you machine language —for that you will need a tutorial. What it will provide is a solid back-up to your language learning and it'll prove a ham memory jogger for even the most hardened machine code programmer.
|
