In computer programming, assembly programming, often shortened to ask, is any programming language where there is a close correspondence between the machine instructions and the architecture’s user code. The architecture is typically a form of microprocessor. Some assembly languages have the capability to directly translate from lower level languages such as C to assembly language. This feature is what allows for true “pipelining”, where a program is written in one language (C/C++ or Java for example) and run on a higher level (asm).
Assembly programming is used in software development to build software applications. Typically the software will be targeted for a particular computer architecture such as x86, arm, or Windows. The assembly language used will help the computer-aided design software to produce executable files that are specific to the computer architecture used.
This type of programmer is highly-trained in a particular field such as programming, but not necessarily a formal technical education. They are typically engineers with solid experience in a particular field. Computer programmers can also be architects or designers doing research at a university or privately funded research center. Typically, a Computer-aided design (CAD) program or software programmer is involved in either concept creation or testing. Often, the interface between the software and the systems it works with is simple. If so, it is usually called “greenfield” interface.
Assembling software programs from source files usually is a distributed computing method that requires communication between the hardware (the computer or microchip) and software (the application or program that runs on the computer). In other words, an application contains instructions (code) and data (syntactical descriptions) that must be interpreted by the computer’s assembler. An assembler is a specialized program that converts an application’s syntax and data types into machine instructions that are ultimately executed on a CPU. The assembler is often written in assembly for compatibility reasons.
One type of assembly programming is the use of “front end” languages such as coder/dispiler tools and softwares. These softwares are written in assembly language for compatibility with the particular assembler. Examples include disassemblers that disassemble and decompile software. Examples of softwares include disassemblers for WinINET, IPC, Windows, Linux, and many others.
A second type of assembly programming languages is used internally by manufacturers and embedded systems. Examples of this are embedded assembly languages developed internally at large computer manufacturers. Examples include EISA (English IT Standard), GIPS, and many others. Some assembly programming languages are designed so that the assembler can be embedded in source code and thus made available to programmers who write source code themselves. Examples of such embedded assembly languages include XELBL, IBM’s assembler, and Sun’s SDK (Software Development Kit).
Regardless of what assembly programming languages a programmer uses, he must have some familiarity with the assembly language. It is essential to understand how an instruction is executed in order to determine if a computer program is well written or not. Furthermore, every instruction must be followed by at least one value that is interpreted into a computer operable form. Instructions that simply carry a different meaning to one computer system than they do to another are called ambiguous.
One of the most important assembly language features is the use of expressions. An expression is a single character used as an expression in an instruction. It enclosed within braces, like this: (Expression as a Squeeze.) An expression can be any character that evaluate to a finite value, but unlike other forms of expressions, the type of value it yields is dependent on the enclosing braces.
A few assembly language features deal with the data flow that passes through the assembly. One such feature is the return value of an instruction. It is a compile-time constant and only differs from one implementation to the next. Another assembly language feature is the conditional expression, which evaluates as the result of a particular expression and then either returns that result or else branches to the next instruction.
The above assembly language features are just the tip of the iceberg. There are many more, all of which are crucial for making quality software. Of course, these assembly language features can be accessed by programmers by means of manual compilation or by using one of the many interpreters that are available. However, the advantage of using a compiler to translate source code into a binary is that all these assembly language features are already available, saving you a lot of time and effort in creating the necessary interfaces. Now all that’s left is to click your mouse and start producing!