Introduction to 8080-8085 assembly language programming. (book reviews) Steve Gray.

Introduction to 8080/8085 Assembly Language Programming

Written by the team that also authored two other Self-Teaching Guides for Wiley, "Job Control Language' and "Using CP/M,' this is another assembly-language book that is best understood if you already have some knowledge of the subject.

By page 12, the authors have introduced registers and flags, without having provided enough background for the beginner to know what they're for. As with other books in the STG series, this one is also divided into frames, which are "short sections in which information is presented or reviewed, followed by questions which ask you to apply the information,' according to an early page. So you get a lot of drill, but unless you already have some background in assembler you'll be learning by rote until it all begins to hang together (if indeed it all does). Perhaps then you can shuffle the various sections around in your mind, and mentally backtrack to reconsider the material you originally took on faith, but not many people can perform such mental feats. It is easier to read the book twice.

The first chapter, an introduction, gives some general material on assembler, goes briefly into bits and bytes, and then on page 8 presents registers, for the first time, without any previous text leading up to A, B, C, D and the other registers. This is no problem if you know something about registers, but if you don't, you'll probably be rather confused, because there are no drawings or charts to help explain what registers are.

Chapter two is on Number Systems and Data Representation, and is written very clearly and simply with plenty of drill work. Then you get hit with chapter three, on Instruction Format, which is bound to mystify the beginner all over again, with a lot of "what' but almost no "why.'

Most of the material required to make a good book for those with some knowledge of assembler is here, but not in the right order. The authors seem to have little sense of how to move gradually from the simple concepts to the more complex ones, and instead mix them together. This is one of the very few Wiley books that miss the mark.

Review Grade: D-