2: Assembly Language

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2.1: What is Assembly Language
Assembly language is a very low level, human readable and programmable, language where each assembly language instruction corresponds to a computers machine code instruction. Assembly language programs translate directly into machine code instructions, with each assembly instruction translating into a single machine code instruction1.
2.2: Assembly Language Caveats
Programmers who have learned higher level language, such as Java, C/C++, C#, or Ada, often have developed ways of thinking about a program that are inappropriate for low level languages and systems such as assembly language. This section will give some suggestions to programmers approaching assembly language for the first time.
2.3: Assembler Directives
Assembler directives are directions to the assembler to take some action or change a setting. Assembler directives do not represent instructions, and are not translated into machine code.
2.4: Data types
While an assembly language has no explicit data types, there are rules for how the data is accessed and stored. This section defines the rules for data access.
2.5: Designing an Assembly Language
The amount of memory directly accessible to a programmer on the CPU (e.g. registers) is very limited. In the case of the one-address architecture, only one memory slot, the $ac, is directly useable by a programmer. Therefore programs need to rely on main memory to store program instructions and data.
2.6: Assembler Programs
The following assembly programs illustrate how the assembly language defined in this chapter can be used to implement some simple programs.