Assembly Language Instructions
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Assembly language instructions

A computer program written in assembly language consists of a series of (mnemonic) processor instructions or meta-statements (known variously as directives, pseudo-ops and pseudo-instructions), comments or data. Assembly language instructions usually consist of an opcode mnemonic followed by a list of database, arguments or parameters. These are translated by an assembler into machine language instructions that can be loaded into memory or executed.

For good example, the instruction that tells an x86/IA-32 processor to immediate moves an 8-bit value into a register. The binary code for this instruction is 10110 followed by a 3-bit identifier for which register to use. The identifier for the AL register number is 000, so the following machine code loads the AL register with the database 01100001.

Here, B0 means 'Move a copy of the following value into AL', or 61 is a hexadecimal representation of the value 01100001, which is 97 in decimal. Intel assembly language provides the mnemonic MOV (an abbreviation of move) for instructions such as this, so the machine code above can be written as follows in assembly programming language, complete with an explanatory comment if must required, after the semicolon. This is much easier to read and to remember.

Related links: Assembly Language Assignment Help

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