Professional Assembly Language

Chapter 1. What Is Assembly Language?

One of the first hurdles to learning assembly language programming is understanding just what assembly language is. Unlike other programming languages, there is no one standard format that all assemblers use. Different assemblers use different syntax for writing program statements. Many beginning assembly language programmers get caught up in trying to figure out the myriad of different possibilities in assembly language programming.

The first step in learning assembly language programming is defining just what type of assembly language programming you want to (or need to) use in your environment. Once you define your flavor of assembly language, it is easy to get started learning and using assembly language in both standalone and high-level language programs.

This chapter begins the journey by showing where assembly language comes from, and defining why assembly language programming is used. To understand assembly language programming, you must first understand the basics of its underlying purpose—programming in processor instruction code. Next, the chapter shows how high-level languages are converted to raw instruction code by compilers and linkers. After having that information, it will be easier for you to understand how assembly language programs and high-level language programs differ, and how they can both be used to complement one another.

Processor Instructions

At the lowest layer of operation, all computer processors (microcomputers, minicomputers, ...