Download What is Assembler? According to Wikipedia, Assembler (for an

What is Assembler?
According to Wikipedia, Assembler (for an assembly language) is a computer program to translate
between lower-level representations of computer programs
So basically it converts Assembly code into machine code which can be run/executed on a computer
machine.
What is Assembler used for?
It is used for converting Assembly instruction code into opcode which basically serve as a compiler but
on a simpler to use level.
Key Terms
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Real number constants
o Real number constants are floating point numbers which have to be expressed
using a decimal point (e.g. -44.26E)
Character constants
o Character constants are singular characters enclosed in quotes or double
quotes. One ASCII character occupies one byte. (e.g. ‘a’)
String constants
o String constants are a collection of characters enclosed in single or double
quotes. Each character occupies one byte. (e.g. “apple”)
Reserved words
o Reserved words are mnemonics, directives, type attributes, operators and
predefined symbols used in assembler and should not be used as identifiers.
(e.g. .386 )
Identifiers
o An identifier is a 1 to 247 character programmer-chosen name of a variable,
constant, procedure or label. First character must be a letter (e.g. _apple)
Directives
o Directives are commands which are recognized and acted upon by the
assembler. (e.g. .CODE)
Instructions
o Instructions are assembled into machine code by the assembler and executed at
runtime by the CPU. (e.g. MOV)
Mnemonic
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Mnemonics are short words which serve as a memory aid and describe the
function carried out by the operation. (e.g. SUB)
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An assembly language instruction can consist of between zero and three
operands which could be a register, memory operand or constant expression.
(e.g. add cbx ebx)
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Comments are ways of letting the programmer communicate information of
how the program works.
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Labels act as place markers for instructions or data by marking the address of
code and data (e.g. myArray)
Operand
Comment
Label